Vol. 13â1959 - NorthEastern Weed Science Society

11 rf',.., 'h.e. ...... ,,,'h.l-i.:"lhoa.4'n ,.:to+_~;l n"(T _1 .Q lThi+.AJ::!;n,:il lJ~T_J.J_ A1AAm_ P; H;1""~c:h and 

BREAKDOWN OF HERBICIDESIN SOILSANDTHEIREFFECTS 

ONTHESOIL mCROFLORA 

1. 

M. Alexander 

Cornell Universit,y 

Abstract 

1 

Interactions between the microbial population of the soil and herbicides 

are of two kinds. Since t:1ese compounds are acting to suppress one type of 

organism. species of higher plants. there is always a possibility that secondary 

inhibi tions will affect the soil microflora. Such inhibitions could have a 

deleterious influence upon crop production by eliminating those transformations 

necessary for fertility. On the other hand. any organic chemical regardless 

of its toxicity may serve as a substrate for the growth of some microbial 

group. and it would then be decomposed and ultimately disappear. This decomposition 

prevents indefinite persistence and serves as an important mechanism 

of detoxification. 

Many procedures have been devised to measure the response of the total 

microflora or of specific physiological types to herbicide application. 

These tests are generally difficult to perform and require long periods of 

incubation. One of the major microbial processes in soil. the decomposition of 

organic matter. may be measured rapidly and wi th a minimumof operations by 

use of the Warburg microrespirometer. Further. the technique permits the differentiation 

of effects upon the indigenous flora and the population bringing 

about the decomposition of added organic materials. The method involves 

measurement of O 2 consumption or CO 2 production with herbicides at several 

concentrations. The data obtained demom:;trate that levels of 2.4-D. 2.4.5-T. 

2-(2.4-DP). 4-(2.4-DB). amino triazole and nonuron required for microbial 

suppression i7ere appreciably creater than those used in agricultural practice. 

An investiGation has been made of the decomposition of various phenoxy 

herbicides and related conpounds by the 13eneral microflora of the soil. The 

disappearance of the compoundwas neasured spectrophotonetrically in soilliquid 

systems using the specific ultraviolet absorption characteristics of 

the chemical. Several phenolic derivatives includinG 2.4-D and 4-(2.4-DB) 

were metabolized readily whereas 2.4.5-T. 2-(2.4.5-TP) and 4-(2.4.5-TB) seem 

to be inert. The concept of simultaneous adaptation has been extended to the 

characterization of intermediates in herbicide breakdown in mixed popUlations. 

the results indicating that 2.4-D is a naturally occurring intermediate in 

4-(2.4-DB) breakdown. 

A number of bacteria have been isolated which are capable of utiliZing 

da.Lapon and TCAas sole carbon sources in mineral media although organic growth 

factors stimulate the rate of decomposition. These microorganisms have been 

characterized and some of the factors affecting the breakdown have been 

established.

2. 

SOt1L Ck\ADIAN WELD ;:'\:3.VLY::;, £8L';'1'" A,.:D SIGNIlICANCZ. 

E. G. Andersoll, Secretar~r, NatiJnal Ueed Commi.t.t.ee 

and Associate Bot~1ist, Science Service, Canada Agriculture 

Ottawa, Ont. 

The earliest at.temrt.a to survev the distribution and incidence 

of weeds in Canada, were tL;se of an Ag~icultura1 Commhsion in Ontario 

in 1880. In 19~1 the committee on Lan6s of the Commission of Conservation, 

Canada, made a survey of some three dozen weeds. During 1930 and 1931 

a further survey was sponsored by the associate committee on weed control 

of the National Research Council and limited to seven major weeds. 

. . 

In 1922 the Canadian Heed Survey was initiated by the Division 

of Botany. During the next 25 years iiI'. Herbert Groh, a now retired 

botanist, made u9 collections and, observations of 12,000 species in all 

settled' areas throughout Canada. One basic aim of this survey was to 

determine objectively,b? a percentage frequency method, the incidence 

of both actual and potential we8ds in belts of meridians across the 

country. These data have been shown to be in close harmony with those 

of much :.:ore laborious procedures. "ihen listing the weeds at any given 

site Hr. Groh felt,in general, that those observed earliest were present 

in greater concentrations. 

"As a first step in assembling the data, field notes were 

mapped on squared paper numbered to indicate meridians, longitude and 

parallels of latitude. Lach of these maps represented 7 degrees of 

longitude ap.dsu:ff1cienc degrees of latitude to cover our cOinparatively 

narrow north-south' agricultural lands. For a widely distributed species 

eight such maps were needed to cOVer Canada from east to west. The 

percentage frequency of a weed in, any 7 degree longitude belt could 

be readily ascertained by co~~arison of the total number of surveys as 

shown on master .sheets with the number 0:1:'occurrences of the weed in 

that belt. For instance mi1kw0edwas found at 570 survey sites in the 

76°_83° longitude belt (central Ontcu'io and northern ~uebec) out of a 

total of 947 surveys, a percentage frequency. of 60.2. These frequencies 

were recorded in tabular form in the seven re~orts of the Canadian Weed 

Survey. (1). This simj?le method produced a r~markab1e amount of data on 

weed incidence .and distribution across Canada that is servdng as a basis 

for studies on distribution. II (2) 

11uchof our data concerning the incidence of p8rsistent 

perennial weeds has resulted from the operations of the Dominion ProvincialCooperative 

;~ed 6urveys started ~n 1949. Unde~ this agroementthe 

Canada Depar-tment of AgriCUlture, through an extra-mural research grant, 

covered, tho uxpenses involved, and through the Division of Jotany undertook 

the overall coo~~ination, identification and taxonomic study of all 

plants collected during tho survey, Tho recipients of tho grants were

3. 

t he .?rovincial Depaz-t.nonts of .Agriculture .:.n .zo.;c cases. In Saskatchewan 

the cooperative arranJoment was with the Department of Zcology 

of the Universi t~r of Saskat chevan, I'he responsibilities of the reci,Jient 

included the engaging of suitable surver personnel, transportation, 

iu~ediato direction of the work and proparation of the reports. 

As the provinces had considerable information concerning tho 

distribution of SOQ0 of their ~roblem weeds, the weeds included in thes.:; 

survoys wore not tho samo in each ~rovince. In }~itoba the survey 

covered leafy spurge, field bindweod and bladder campion. Leafy spurge, 

toadflax, hoary cress, hussian knapweed, field bindweed and poverty weed 

were included in the Saskatchewan surveys. Canada thistle and ~erennial 

sow thistle werJ two of' the seven weeds survGyed in Alberta. (J) 

In 1951 the provinco of British Columbia joined in these cooperative 

surveys and it was egreed that specimens of cow cockle and St. 

John I s wort were to be collected in addition to th;; other p,.rennic.l weeds. 

In each case th;; sUI~ey teams were instructed to locate, list, 

;"ap and col Iect specimens. Records wers also to be kept of the more 

cownon woeds of the district and ro)orts and col18ctions made of any 

spccacs not previously roported. Thoso survey beams operating in areas 

boli0ved to be favourable for the growth of halogeton were issued special 

instructions concerning this weed, 

He '.re indebted to Prof. R.T. Coupland, Head of the Department 

of Plant LcoLogy, Univorsit:: of Saskat-chewan for tho f'oLl.owd.ngInf'oruat.f.on 

(4) concorning th0 method used in his province. 'rhe methods used in the 

other provinces have aeen similar in many resp0cts. "Twomethods of survey 

have been used - thl) c.ct.ai Lod survey and tho t.ranscct, survey. In areas 

where the infestations arc not numerous, a L,rm to f'ar'm survey is made in 

an effort to locate every infestation of each weed, Inf'ortnat.Lon obtained 

from agricultural representatives and municipal officials is used in 

finding tho first infestations. A detailed surve: is thon made of the 

adjacont farms to which the vceds have frequently spr-ead, In parts of 

the municipality whero nona of these \leods has been reported, a farm to 

farm survey is made .n order to discover wheth_r the lack of rc)orts is 

due to the lacx of knowledge conccrning tho idontity of the weeds. 

Fr equent.Ly nevi infestations arc. round in this way. In detailed surveys 

of this type, an average of about 40~ of the farmers ara contacted in 

each municipality surveyed. The transect survey is used wh0re infostations 

arc too numerous to 1 arrant the investigation of l ver:.' one. 

This method has only been used so far with respGct to toadflax in 

R.H. 442 and municipalities (or parts of thcm) nearby. Tllis involves 

sampling of the infestations in a milo-wide strip through the centro 

of each township. Every accessible farmer living or working in this 

strip is contacted and information is ootained concerning all the land 

which he nperates. By this method information is obtained concerning

~ach surv~y r~~ort yields d~ta of valUe; to thOS6 conductin6 

t hc control eamnaf.zns , It has been shown, for:;xaL:Dle. that J7%of the 

_ 

an aver-ago of between 35-40;b of the quar-ter sections in tho municipality. 

These data arc thon used to calculate tho probable extent of the total 

infestation. 

Each survey is conducted en a municipal basis and a report 

is sont to thb municipality tog~ther with a list, indicating tho 

ox .cn't of each infestation, and a map showing tho location;; of all 

infestations. 

Resurveys arc mQrle in so~c are~s to obtain informution concorning 

the rate of Lncr-oas, in abundance of these species. At that 

tine de t ai.Lod sur-veys arc rupoat ed , while fre;,l transect resurvoys 

Lnf'crs.iat.Lon is obtainod. conccrntng the same quarter sections which 

Here visiteci in tho originJ.l survey. II 

Th~ acreages known to be infcsted with certain persistcnt 

por-cnn La.L \"rOe;dsin :i.:stern Caneda are listod in Tablo L Nost of t:.is 

infornation has been r cvca Icd since t.hc inception of tho coopor-atdv; 

surveys, Al.though tho situation, e spccf.aLl.y in Saskatchewan and 

Alberta, is a Larm.ing , each subsequent survey adds greatly to the 

totals and only small parts of each )rovincc have been surveyed. 

. 

••••• _ ,_'. __ ~_. _ ..... 

\-ieod 

•. _ .... __ 

j'ianitoba 

D __ .. _. ___ 

Saskat- 

.!lh.flli~__ 

Alberta 

.______ 

British 

C.9lumbia_____ 

Totals 

Russian Knapvecd 

Centfl_~ rOD8n.§. L. 1,899 10,560 30 12,489 

Hoar:' crosses 

Ce.rdaria s-p, patches 1,356 128,000 600 129,9J6 

Field bindwood 

Convolvulus ~r:.- 

v~1sis r: 13,920 4,681 26,400 1,('00 46,001 

spurge 

Buphorbia ~ L. 8,000 7,706 39,680 100 55,486 

~oafy 

I'o.idf'Lax 

Linaria 

vulg;:,.ris 

Hill .)atchvS 134,602 319,000 475 454,(177 

,...A._u__ ". ••• _."- -.... _._. _,_o",~, .• _. _.__.. -"~"--"'--'- '-'-~"'-'- 

-_.......... -,..._._....__..._-~~.- -

5. 

drop)ud from cultiv&tion usually because of th0 woed. Tho other 16~ 

occurs in lund which has nover be"n cultiv"ted. By cOinp;;:.risoneightysix 

p~rcont of the toadflax was on cultiv&tod lLind at tho time of the 

survey, 

Resurveys have shown that leafy spurge doubles its hold in two 

yeurs despite Gxtensive control caL1paigns. In 1958 Saskatchewan used 

215,000 Ibs. of Atladde, 2,500 Ibs. of Nonuron and 384,000 Ibs. of 

concentrated Borascu against persistent perennials. 

Anothor t ypc of survey yields va.IuabLo information as to the 

Uillounts and value ef the herbicides sold. Under tho terms of tho Pest 

Control Products Act, all hcr'bd.cf.dcs have to bo registered with the 

Plant Products Division of our Department of ~griculturo oefore they 

can be offered for salo in CLinada. All firms who register products arc 

circularized by the Dominion Bureau of 0tatistics and are thus enabled 

to compile data as to the types, amount.s and value of the herbicides 

sold each year. (5) Only reports from firms which showed sales in 

excess of :::>5,000were actually used in developing the details shown 

in Table 2. It is estimated that this group accounted for at least 

95)0of the total sales. 

This information is a further guage as to the sales Lind/or 

use of any particular product and any significant trends may be observed 

by compar-Ing earlier reports. In 1957 the total value of herbicides 

sold was ~,450,423. This was only a half million dollars less than 

the figure for the sales of agricultural dusts and sprays. In 1958 

a total of 405 herbicidal products were registered for sale in Canada, 

an increase of 50 over the previous year. 

m!!..i?.and amounts of herbicides 

used agriculttg'_ally 

Each year since 1947, the \leeds Commission of tho Nar,itoba 

Department of ~gricultu.e has conducted a survey by correspondence to 

indic~te details of the herbicides used agriculturally in Western Can~da. 

All companies processinG or distributinG herbicides were a.skod to 

re ort the quantities of each product used, and the re.;)lies were treated 

confidentially. Table 3 is a sample of the questionnaire used and 

Table 4 gives the major part of their re ort for 1958. 

Unfavourabll.l '.Ie ther conditions during the early part of the 

season was largely reeponatbl,e for an 18~o reduction in the use of 

hormone ty)C herbicides. The total acreage treated with 2,4-D and 

tWPAwas 12,737,000 acres as compared to alnos t 15i- million acres in 

1957. ~eductions were noted in tho ~nounts of MCPA,TCA, and dust

6. 

used. The acreege trc;}.ted by aircrc.:ft a'l so snowed a reduction. Ninety 

" of the 2,4-D used lias estor while 51;; of tho HCPAwas amrne and 41;

Night-floc;ering catchi'ly and ribgrdss "show up" frequently in samp.Les 

from Lastern Canada and stinkweed and ball mustard in t.ooso from Hestern 

Canada. 

It is hoped that this outlin0 of some weed surveys has been 

~f interest. Further information may be secured by consulting the 

original sources as givon below. 

Literature 

cited 

1. Canada, Department of Agriculture, Canadian Weed ~urvey Reports 

1-7, 1942-1948. 

2. Frankton, C. Weed control and weed biology in Canada. 3rd Br. 

Weed Cont. Conf. 1956 Proc. (1) PP195-173, 1957. 

3. Craig, H.A. Federal-Provincial Weed ;:,urveys in ~!estern Canada. 

4th Hest. Can. Heed Control 00.1f. 1950 Proc. ppl44-148, 1951. 

4. Coupland, R.T. The Saskatchewan \/eed Survey. Himeo. Circ. No. 35. 

Univ. of Sasle., College of Agric., Dept. of Pl. EcoloJY, 

Saskatoon, Sask. Feb. 1955. 

5. Canada, Dominion Bureau of Statistics. Sales of pest control 

products by Canadian registrants, 1957. Dominion Bureau of 

Statistics ;'lemorandum, Ott ava , Ont , 1957. 

6. Suggitt. J."r. Brush control acreage sprayed in Canada - 1957. 

12th Heet. z.e.st. Section National ~:eed Cttee. 1958 Proc, in 

press. 

7. Canada, Seed drill survey reports. Provincial Department of 

Agriculture, 1927-1958.

8. 

Table 2 

u. 

Sales of herbicide", b~' Canadf an registrants 1r 

Irerbicides Uni t of ;;easure 

Arsenicals 

Berates, chlorates and 

borate cnl.ora t e mixtures 

Cyanamides and Cyanates 

D1nitros 

I P C 

n:.;. 

TeA 

Imp. 

lb. 

lb. 

lb. 

lb. 

lb .of 

" 

" 

" 

ECP* 

2,,1,'5-T forr,lUlations, 

it 

ester 

,~mine 

2,~-D fornulations 

""ester' dust 

ester liquid 

amine liquid 

other 

2,~-D,2,·~,5-T mixtures 

2,4-D portion " 

Other 

2,G,5-T " " 

herbicides LncLudi.n-; ni.nera.L 

Gal. 

acid 

oils 

Total value of herbicides 

*Firms reportinc }[ C P, 2,"1,5-T and 2,'i,-D '.Iere asked to record 

, their sales on a basis of acid equivalent i e , 

(a) 10,000 gallons of a 6~ oz ester .rere to be recorded as 

~&0,000 lb. 

(b)lOO,OOO lb. of a 2,1-D 5~ dust were to be recorded as 

5,000 lb. 

(c) 5,000 gallons of'an 80 02 amine vrere to be recorded as 

25,000 lb. 

)l 

17 Copied fro!.: "Sales of Pest Control Products by Canadian Registrants." 

12 nonths ended

9. 

Table 3 

fa i.~L 

Gentlemen: 

~ COPY(~F QU~STIOiiNAlREd)SED BYTHIi:MAjHTOr;A 

DEPART~l.8NT OF AGRICUL'I'U1'l.£ liEED5 CON1HSSION 

169 Legislative Bldg., 

j-;'innipeg 1, Nanitoba, 

September 8, 1958. 

CCl]'ANIES PROCESSINGOR A,G'l'INCr .".&MAINAGENCIESOF HERBICID;';& 

'Weagain seek your cooperation in connection with the Annual 

Survey having to do with chemical treatment of crops for the control 

of weeds in Hestern Canada. Due to the increased use of HCPAit is 

desirable that we sU0divide it into the various formulations. An 

early return will be a) reciated. 

Wethank you for your' as.istance in the past and will look 

forward to J~ur continued help. 

Yours truly, 

f9JfU~~ 

H. il.. Craig, 

Chairman, ~eeds 

Commission 

QUESTIONNAIR:'; rlE 2,4-D, MCPAANDALLIEDH~R:8IG:wtS uSED IN 

. \IE6TERN C;.N.J)1l.- 1958 _ 

(Please return as soon after season closes as possible to: 

The Weeds Comr.:ission, 169 Legislative Bldg., Winnipeg, j·ian.) 

2,4-D Ester 

2,4-D Amine 

I;CPAEster 

II Amine 

Acid ~uivalent 

British 

Lanitoba $askatchewfg! AlbertI:!:' Columbia 

II Sodium Salt _ ..__ 

2,4-D Dust (lbs. Acid) _ _ 

LCPADust (Lbs, Acid) _ 

TCA(total Lbs . mat.er-La.l.) ·• .____ _ _ 

2,4-D, 2,4,5-T or brush control mixtures for brush control, etc. and 

not included above. 

Any other chemical 

Remarks . 

--------, 

Reporting Company 

Address, __ 

Per _ _ Date . _

10. 

Provo 

Han. 

Sask, 

Alta. 

B.O. 

Provo 

Han. 

Bask. 

Alta. 

B.O. 

kf'L.i..£..l: 

Acres. .JL 

98,000 . 21.7 

171,000 42.5 

388,000 51.7 

217,000 40.6 

%Spray 

1221 1222 

97.3 97.4 

96.6 96.3 

98.1 98.3 

~~ ..97·3 

Formulations 1958 

2,4-D ester 

2,4-D amine 

HOPAester 

HOPAamine 

i'iOPASod. Salt 

Acres . 

10,083,000 

1,037,000 

657,000' 

825,000 

135,000 

DETAILSOFhPPLICATION 

~;4-b& HCPI 

%Dust %Ground ~P. 

.!2..2112.2§ ill.? 8 

2.7 2.6 99.5 99.7 

3.4 3.7 97.8 98.3 

1.8 1.7 98.7 99.3 

.s, 

79.2 1947 

a.i :1948 

5.1 : 1949 

6.5 1950 

1.1 1951 

1952 

Sodium Salt 

Agree ...! 

89,000 19.7 

8,000 2.0 

33,000 4.4 

...iJ2QQ tthl 

135,000 .M 

%Ai;r,g:aft 

·1257 ~ 

.5 .3 . 

2.2 1.7 

1.3 .7 

500,000 1953 12,121,000 

4,000,000 1954 11,179,000 

8,200,000 1955 14,002,000 

13,566,000 1956 16,347,000 

11,326,000 1957 15,476,000 

13,497,000 1958 12,737,000

11. 

TablG 5 

._____ProlLinee 

P':rcen"a6 e ;;rarling 

No. of 

_....§.?l.l,Jles__ .. No:-i--=}~=~2-·". No ..... .3.-- Rejec~~df 

a£t .A.I. ..£l'~'[t~ .YJ ....12J£i 

Prince Edvard Lland ).,044 9.0 7.0 16.0 68.0 

Nova Scotia 1,009 26.0 8.0 1.3.0 53.0 

New Brunswick 109 23.0 11.0 9.0 57.0 

~uob()c 737 l1.C 2.0 10.0 77.0 

Ontario 785 47.4 10.0 21.0 21.6 

11anitoba 1,007 8.0 8.0 17.0 67.0 

Saskatche\Jan 847 29.0 1.1 39.1 30.8 

Alberta 1,225 13.3 15.4 22.3 49.0 

Jritish Columbia 322 13.4 20.2 17.1 49.3 

Part 51. sine,:. 1954 

NewBrunswick 263 29.0 10.0 14.0 47.0 

~uGbec 976 26.4 11.2 16.5 45.a 

Ont.)rio 746 49.0 10.0 10.0 31.0 

i.ani.t oba 566 4.0 28.0 23.0 45.0 

Saskatche\lan 1,.377 13.9 16.8 26.6 42.7 

Al.ber t a 40.0 13.0 16.5 ]0.5 

jritish Colwnbia 296 12.0 21.0 21.0 46.0

) ) 

Occurrence of primary and secondary nO:~0us weed seeds in trade and official samples of red clover, 195' 

>, 

H 

°..., 

~ 

° 

~ 

'd Q) 

Q) 

to 

'0 

..., CD 

UJ 

..., '" 

'" ill 

~ 

~ 

'" 

~ 

PRII:''J('[ NOXIOUS 

Cl 

I:l 

..-l 

° ..., 

..... P< "'»'rl '" '" CD 'd 0) 

g ~ ~ ~ ~ ~ ~ ~ ~ 

O",OCIJIO""'rlH 

~ AROU1rdO 

~ 0 g Q) S ° a & H 

'0'

CV\ 

rl 

)~!1ce 01' priLJary and secondctry noxious weed seeds in trade and O1'ficial. samples of wheat, 1957-58 

PRII1'I.RYNOXIOUS 

S'ECm1IloillYNOXIOUS 

'C1 

'tJ 

Q "J I'-i 

-P (]) Ul Ul ('j cd 

eo r-l Ul 

-P o I'-i 

[Q 

~ 

c; -P r-l cJ 

0 .0 'tJ [Q r-l '" ~ ~ ,::1 :,., ..., -P 

-P (l) -rl (]) 'C1 '0 -P 1>0 I'-i r-l 'tJ 'tJ rc Ul 

cJ t1 Ul r-l H ,Lj H tu 'C1 (l) 

'H

14. 

NEWRESEARCHONTHETRANSLOCATION OF HERBICIDES 

A. S. Crafts * 

Research carried out during the past ten years on the translocation 

of 2,4-D in plants seems consistently to indicate that this compoundis 

moved in the assimilate stream from regions of food synthesis to regions 

of food utilization. Short distance movement, such as that from epidermis 

of leaves to the phloem and from phloem to meristems and storage tissues, 

apparently takes place within the interconnected cell system, the symplast. 

Long distance rapid translocation takes place in the sieve tubes of the 

phloem. 

Using c 1 4 labeled 2,4-D, a freeze-dry technic for plant preparation, 

and the auto radiographic method fir following the tracer, we at Davis 

have been able to show that 2,4-D applied to a leaf will penetrate the 

cuticle, migrate to the -phloem and move with foods from a mature leaf in 

the light to the apical meristem, to the roots, or to both, depending on 

the location of the leaf on the plant. The tracer will not move out of 

a young leaf that is still importing food, nor from a chlorotic leaf of 

a variegated plant. 

Movementto roots depends upon their activity; if they are growing 

rapidly 2,4-D* may.move into them and become widely distributed; if they 

are growing slowly or not at all 2,4-D* may move toward them along the 

stem but may never arrive in the roots. 

Results of our tracer studies with 2,4-D* substantiate many field 

results with this compoundand account for successes and failures of 

field applications. Whenamino triazole was made available for trial 

it proved to translocate in plants, and in some instances seemed to 

move more extensively than 2,4-D and under somewhat different conditions. 

This naturally led to the question, do all compoundsmove similarly in 

plants or are there fundamental differences in the mode of their transport? 

Comparative mobility of labelled tracers. Wehave always thought 

of 2,4-D as a translocated herbicide and we have not been able to tell 

how well it translocates. Whenwe obtained labelled samples of amino 

triazole and maleic hydrazide we were able to put on comparative tests 

and we found that of the three 2,4-D is the least mobile. 

A group of mature Zebrina plants was selected for this experiment. 

They were healthy but somehat pot bound and the roots were not very * 

active. Whenthree mature leaves on the stem were treated with 2,4-D 

the tracer stayed near the region of application moving only throughout 

the treated leaves and for a way along the stem. Similar application 

of amino triazole* resulted in movement into all active shoot tips and 

into the root system as well. All mature leaves along the stem were 

bypassed. - 

In the case of maleic hydrazide~~ the .tracer moved in coneiderable 

amounts to all actively growing shoot tips, it moved into the root

system, arid all intervening leaves show to varying degrees in the autograph. 

According to our interpretation the 2,4-D* moves in the phloem but when 

movement is slow it is absorbed out of the moving stream by active cells 

along the way and it does not get very far unless movement is very rapid. 

15. 

Amino triazole seems less subject to absorption and hence moves to 

the various sinks even though transport is slow. It does not enter actively 

exporting leaves. Maleic hydrazide also is not subject to uptake by liVing 

cells and it moves throughout the phloem system. However, it apparently 

leaks from phloem to xylem and hence is carried via the transpiration stream 

to all transpiring leaves. Since it may SUbsequently move out of such leaves 

it seems apparent that it may circulate in the plant. We are certain that 

phosphorus does this and maleic hydrazide apparently attains the same 

distribution. This is the ideal distribution for systemic herbicides, 

insecticides and fungicides. 

Whenthis experiment is repeated using barley seedlings we obtain a 

similar picture except that in these plants amino triazole also seems to 

leak from phloem to xylem. Both ATA*and MH*accumulate to high concentrations 

in the root tips. 

In the above experiment the second leaf of each plant was treated. 

At Oxford an experiment was perfo~ed in which 2,4-0* was applied to 

leaves number 1, 2, 3 and 4 of separate plants. The autographs showed 

an interesting relation, namely that the first expanded leaf moved the 

tracer to the roots in high concentration indicating rapid flow of the 

assimilate stream. The second and third leaves also gave evidence of 

feeding the roots. From the fourth leaf, in contrast, there was no movement 

of the tracer to the roots; but there was a high concentration in the 

basal portion of the leaf and in the young fifth leaf. It seems that there 

is a division of labor in these grass plants. As they start off the first 

expanding leaves very actively nourish the roots whereas, as successive 

leaves come along, they become more involved in feeding the young leaves 

and inflorescenseand less in feeding the roots. As older and older plants 

are treated movement of 2,4-n* from leaves to roots becomes less pronounced 

until, as flowering occurs movement of foods from leaves to roots must be 

very slow. 

With this relation in mind a comparative study on seven labelled 

compounds was made using barley plants with five fully expanded leaves. 

Since leaf number one on these plants was starting to dry up, treatment 

with each chemical was made to leaf number 2 and leAf number 5 on separate 

plants. Autographs of these plants showed the following results. From 

leaf number 2 a slight amount of 2,4-D* reached the roots; from leaf 

number 5 none. In the case of indole acetic aCid*, an appreciable amount 

of the labelled compound reached the roots from leaf 2, none from leaf 5. 

ATAi~ from leaf 2 was present in the roots at an intennediate concentration; 

from leaf 5 it was present in appreciable quantity. MHfrom leaf 2 wae 

highly concentrated in the roots; from leaf 5it was in medium quantity. 

Urea* produced a strong image in the roots from leaf 2, an appreciable 

image from leaf 5. We suspect in this case that the urea is rapidly 

hydrolized in penetrating the leaf and that the labelled C02 is converted 

to sugar. Chromatography of roots of urea" treated plants has produced a 

sugar spot, not a urea spot.

Leakege of 2.4-D from roots. Several additional observations on the 

use of labelled herbicides should be of interest. Back in 1950 one of my 

students found that if he put a droplet containing 2,4-D on the lower leaf 

of a cotton plant growing in a culture solution, symptoms appeared on a 

second cotton plant growing in, the same culture jar. I was interested in 

checking on this phenomenon, I grew barley, bean, Zebrina and cotton plants 

in cul.t.une.rao'Lut.Lona and in each culture I had one cotton plant that acted 

as an untreated receptor •. I treated the plants of the four species with 

2,4";"D-l~ in replicated series with dosages of !, 1 and 2 microcuries. After 

24 hours I killed and freeze-dried one series and after 15 days I killed 

and freeze-dried the others. In each case the untreated receptor cotton 

plants harvested 'after 24 hours -gave light but positive autographs after 

8 weeks exposure Onfilm. And samples of the culture solutions from the 

jars of treated plants gave poeitivecounts when dried on planchets. The 

receptor ~lants allowed. to, go for '15 days gave more dense au tog raphs and 

the 2,4-D was concentrated in theyo,ung shoot tips that were beginning 

to show 2,4-D symptoms at the time of harvest. This is positive evidence 

16. 

In the case of monuron" no ~bvement into the roots of barley was 

found; only acropebad, movement to the tips of the treated leaves. We 

think that this substituted urea is unable to enter the phloem and move 

in the assimilate stream. Dalapon~~ moved freely from leaves to roots of 

barley and, we auspect, that it approaches MH*in mobility. An interesting 

observation is, that the more~bile compounds in this series appear in 

greatest concentration in the untreated mature leaves; evidently the more 

mobile a compound is, the more readily does it leak from phloem to .xylem 

and move in the.transpiration stream. 

To,study the relative roles of penetration and translocation in the 

movement of these labelled tracers an experiment was performed using blocks 

of potato tuber tissue. This represents a relatively unspecialized type 

of cellular tissue that expresses only the absorptive and accumulative 

capacity of non-vascular cells. When the first six of the above compounds 

were applied to thes~ potato tissue blocks and allowed to react for period. 

of 2, 4, 8 and 16 days, it was found that 2,4-D* was absorbed by the liVing 

cells but moved very littJ.,e; ATA*moved somewhat more extensively; MH*in 

16 da¥s permeated the whole block •. lAA* moved a bit more freely than 

2,4-D and it accumulated and moved particularly in the phloem strands. 

Urea*was ·found to move only in .Low concentration and in 16 days was almost 

entirelygont, from the tisslle.', Apparently it is split by urease and lost 

to the atmosphere as C02*. l{Qnuron, on the other hand, did not enter the 

living cells but appeared to diffuse along the cell walls and concentrate 

around the -outer surface of the tuber block. Apparently it moves only in 

the non-liVing cell-wall phase of-,the tissue. 

, From the fact .that, the~eri~s2,4-D~~, ATA*, MH*shows the same relation 

of increasing mobility in undifferentiated potato tuber tissue as is shown 

in barley, it seems that trGnslocation per se is probably seldom limiting 

in plants. The factorsote~cumulation during the penetration process and 

absorption and accumulation from the assimilate stream during translocation 

apparently overshadow transpprt in d-etermining distribution of these 

compounds. And th~lesson to be: learned is that in our screening programs 

we should ever be alert for more and more mobile compounds.

17. 

for the leakage of 2,4-0 from treated plants into the culture medium. 

Similar evidence was f~und for leakage of trichl~robenznic acid from 

roots of treated bean plants. 

Duration of uptake. Another expQriment involved 24-hour and l5-day 

treatments with 2,4_0'lF on the upper leaf surface of Zebrd.na., The autographs 

show that, even though the droplets were dried up within an hour or less, 

the l5-day treatment resulted in the uptake of much more 2,4-0* than did 

the 24 hour treatment. Because the upper leaf surfece of Zebrina has no 

stomata, this means that penetration of the 2,4-0*, formulated in 50% 

alcohol and 0.1% Tween 20, continued for hours and even days after the 

droplets were dried down to a film. Subsequent time series running 1, 3, 

9, and 27 hours and involving 2,4-0* and MH*confirm this continue~ uptake 

of these chemicals from such formulations. 

Where 2,4-0i~ is applied to the roots of plants through the culture 

solution there is a high accumulation of the chemical in or on the root 

cells and a relatively small amount moves into the tops. In a comparative 

test on barley seedlings 2,4-D* and urea" showed this high accumukatdon 

in roots and little movement into tops. ATAi~, MH*, IAA*, monuron*, and 

dalapon* moved into the tops in appreciably higher concentrations. 

Additional tracer studies. One experiment involved use of two lots 

of labelled isopropyl ester of 2,4-D, one lot labelled in the carboXyl 

carbon, the other in the C3H7chain. Whenthese were s~tted on barley 

leaves and left 24 hours tne carboxyl labelled tracer moved into the ro.ts 

in the same way as did carboxyl labelled 2,4-D acid. In contrast the 

alcohol label remained in the area of treatment. This indicates that the 

isopropyl ester of 2,4-D is hydrolized during penetration and that the 

alcohol chain remains in the foliage. It would be very interesting to 

repeat this using lots of a heavy ester of 2,4-D. 

As mentioned above dalapon* was found to be freely mobile in barley 

plants. It also moves with ease in cotton seedlings and very notable is 

the fact that the opposite cotyledons that were untreated contained an 

appreciable quantity of the tracer, this despite the fact that the plants 

were freeze-dried. This supports the conclusion that the .compounds.that 

move most readily in plants apparently leak from phloem to xylem and 

circulate most readily. 

Tests a.t Davis, California, with labelled E. P. T-. C. show that. . 

this volatile compoundmay be absorbed by the leaves of bean plants and 

translocated throughout the plants with fair concentr~ti6ns being held 

in the roots. This adds one more to our list of readily transl~cated 

herbicides. 

Finally trials with labelled herbicides on the fronds of bracken fern 

have confirmed the relative mobility of the series MH*dalapon* ATA* 

2,4-D* that seems to hold in barley. Undoubtedly the comparative autoradiography 

of pll'lnts using labelled herbicides holds t.remendoue promise 

as a method for studying the physiology of herbicidal action.

18. 

MODEOF ACTIONOF VARIOUSHmBI:CIDESAND 

THEm roSSIt!LE SITES OF ACTION11 

2/ 

J. 1. HUton- 

Abstract 

A search for m9ta boli tes that will part1.ally or completely reverse 

the inhi.b1.tory· act1.on of harb1.c1.des Q'l growth of various organisms has 

impltcated phys1.ological processes that are prol::ably 1.nhib1.ted by 

herb1.cides. The metabolites that have been found to reverse the inhibitory 

act1.on of several herbicides and the physiolog1.cal processes impl1.cated 

as the growth-l1.mit1.ng processes 1.n the presence of the herb1.c ides are as 

follows: . 

Metabolite 

adenos1.ne triphosphate 

Herb1.cide 

pentachlorophenolox1.dat1.ve 

Phys1.olog1.cal Process 

phosphorylat1.on 

yeast nucleic acid, purines 

and purine precursors 

i3-alan1.ne, pantoate and 

pantothenate 

am1.trol . synthes1.s of pur1.nes 

ehloro-subst1.tuted synthea1.s of pantothenate 

aliphat 1.e acids 

carbohydrates 

carbohydrates 

si.maz1n 

phervlureas 

photosynthes1.s 

photosynthesis 

Theinh1.b1.t1.on of pantothenate synthesis was 1.nvest1.gated 1.n deta1.l 

and the pantothenate-synthes1.zi.ng enzyme 1.mpl1.cated as one of the s1.tes 

at: action for the chloro-subst1. tuted al1.phatic ac1.d herb1.cides. The 

mechanism of act1.on was 1.c'lent1.f1.edas compet1.t1.on between herbicide and 

pantoate for a s1.te on the enzyme of synthesis. This discovery was 

ut1.Uzed 1.n the synthes1.s of new phytotox1.c chem1.cals. 

11 To be presented at the Northeastern Weed Control Confere nee, January 

7-9 1.n NewYork, NewYork as an invi tat ional paper. Data to be 

published 1.n extensia by J .1. H1.lton, W.A. Gentner, D. E. Moreland, 

L.L. Jamen, and J .5. Ard 1.n WEEDSand PLANTPHYSIDLOGY, 

Y Plant Physiologist, Crops Rese a'eh. D1.vis1.on, Agricultural Research 

Service, U. S. Depar'lment of Agr1.eulture, BeltsvUle, Maryland.

19. 

THE USE OF HERBICIDESIN CONSH..RVATION 

Justin W. Leonard 1,/ 

The tem "conservation" is used in so many contexts as to require 

redefinition whenever it is employed by people concerned with different 

fields of endeavor. In this paper the tem will apply to the efforts 

of an agency of state government to manage renewable natural resources 

on public lands in such a manner as to maintain or increase both supplies 

and utilization of forests, fish, and game birds and mammals. In such a 

program the dominating policy is that of multiple-use. Hence, prcblems 

are more complicated than they would be if the objective were to advance 

a single resource int~rest without regard for the welfare of others. For 

this reason, the observations made here will center largely on the 

situation faced by the Michigan Depertment of Conservation, with which 

the writer has greatest familiarity. In our 'present stat.e of knowledge 

it would be foolhardy to depart from this admittedly provincial approach. 

But there would appear to be some close parallels between Michiganls 

problems and those of the Northeastern states. 

Forestfi. Herbicides have two major uses in forest·management ;.t 

present; (1 as a debarking agent for standing pulpwood, and (2) in the 

control of undesirable or unwanted trees and brush. 

Chemical debarking agents would appear to have considerable economic 

value, since pulpwood stands so treated might be cut at almost any time 

of year and hence permit more efficient utilization of manpower. Satisfactory 

materials and methods, however, remain to be developed. Experiments 

have been conducted with various chemicals (McCulley, 1957) but only 

sodium arsenite gives relia9le results. And for several reasons this 

material is out of favor with pulpwood operators in the Upper Great Lakes 

area. For one thing, repeated instances of mortality to wildlife have 

occurred, with attendant unfavorable public reaction, and hazards to 

human life have been noted in post-treatment inspections. It should be 

noted that these accidents and hazards are almost entirely attributable 

to sloppy,poorly supervised application of the chemical. Also, wood so 

treated sometimes requires additional treatment in processing plants, and 

these factors, coupled with the appearance of effective portable mechanical 

peelers have resulted in the use of chemical debarking agents dwindling to 

the vanishing point in Michigan. Development of an efficient, economical, 

chemical debarking agent free from the hazards of sodium arsenite would no 

doubt be welcomed by forest industry, and continued research seems well 

warranted. 

1/ Assistant Deputy Director, Michigan Department of Conservation

20. 

The control of undesirable or unwanted trees and brush has application 

in q number of situations.in both forest and game management. For the 

forester, obvious uses for herbicides include: . 

(1) Planting site preparation'- Aerial or ground anplication of such 

herbicides as 2,4-D and 2,4,5-T has advantages in providing 

improved accessibility and visibility for planting operations,and 

in removing overgrOwth which might weaken new plantings tbro1;lgh 

competition and sha.ding. . . , . 

(2) Plantation release. Many pine plantations made some years ago,' 

especially those performed b,y the Civilian Conservation CorPs in 

the 19)0(s , are showing the adverse effects of overtoppingb,y 

.'various species of non..merchantable trees now in advanced stages 

of grOwth~ Aerial epplicationof hormone-type herbicides is 

, especially effective in achieving satisfactory release at moderate 

cost. . ' 

() Control of oak wilt disease. Girdle or frlll applications of 

herbicides to treesirifectedwith oak 'wilt and adjacent healthy 

oaks are effective inpreveriting spread of the disease to nearb,y 

trees b,y means of natura.l root grafts. ' 

(4) Road, fire line and right-of-way niaintenance. Herbicides 

applied 'in a variety 'of ways are effective in controlling brush 

and undergrowth where clearings must be maintained for fire lines 

or for road and other righte.-of..owa;v. This is another sensitive 

area in pUblic relations, where close silperivision of work crews 

will pey dividends. 

Depending on the problem at hand,foresters may use any or all afthe 

commonmethods of herbicide·application----basal spray, stump treatment, 

girnles or frills made b.YaXes or special cutting tools to receive direct 

:,.pplication of the chemical, and folie-r sprays' ciellvered from ground .. . 

sprayers or from aircraft. . 

There is an extensive body ofl1terifture dealing with the use of 

herbicides in forestry. Reference may be made especially to pUblidations 

b,y Roe (1955); Arend (1956);ltudolf and Watt (1956); and b,y various authors 

in recent annupl reports of the Lake States Forest Experiment station. 

At present,on National FGrests in the Lake States, between 6,000 and 

8,000 acres per year are being teated for plantation release. Hichigan has 

not yet undertaken such treatment on its Stete Forests for two principle 

reasons: It is anticipated that scrub oak, the species responsible for 

most overtopping. ~.y soon have greater value as a pulp soecies and hence 

constitute a valuable timber resource in itself; further, scrub oak are 

important mast producers for deer, and this value must be considered where 

multiple-use concepts prevail.

21. 

G.:unemanagement. ',hile the fact is not as Winely recognized as might 

be desirable, modern game management is concerned to a verylerge extent 

with habite.t improvement. The artificial propagation of game birds and 

ma,nmals on government-operated game farms still has some place in c~ntempora~J 

op~rations, but it is the consensus of the profession that, under today1s 

season an 4 bag restrictions, natural reproduction has a good chance to keep 

up with gun pressure for year's to come provided native species of game birds 

and mammaLs have optimum habitat. For this reason, budget allotments 

earmarked for game management are increasingly being plowed into manipulation 

of the E::nvironment; and game research expenditures are heavily slanted 

toward discovE::ring better meth~ds for achieving such manipulation. 

In searching for to~ls which will permit manipulation of the environment 

with the game production in mind, a primary consideration is cost. In 

an intensive farming operation comparatively high costs may be a good 

investment; however, when public revenues must be spread over extensive 

acreages of public land, even sums which seem l

22. 

opbnings frbe from trees and shrubs if they are to mate 

succbssfully; and deer, of course, do not find optimum conditions 

in unbroken forest. To create such openings we have 

tested 2,4-D, 2,4.5-T,"Brushkiller," Inverton, and for such 

hard-to-kill species as maple, Kuron. 

(2) To elimiru>te or change Succession in aquatic vegetation. Herb 

the critical problem is to create and maintain open water in 

small water impoundments perhaps only a few acres for waterfowl. 

and incidentally for muskrats and certain other fur bearers. A 

whole spectrum of aquatic growth may present problems. Sedge 

and rush meadows, dense beds of cattail and phragmites, both 

submergent and emergent beds of various rooted aquatic plants, 

as well as Shore-inhabiting shrubs including both ericaceous 

species and o'the r forms such as button bush, dogwood, and willow 

often require control. We have used Dalapon and ftJminotriazole 

for sedge and rush control, Dalapon holding the advantage in cost. 

For ericaceous species, we have depended largely on _~te. 

(3) To encour2ge sprouting of food and cover species. In recent 

years we have learned that a sublethal aerial ap~lication of 

hormone-type herbicides qy air to aspen stands may greatly 

stimulate the production of natural sproutll from roots. These 

sprouts provide an excellent supply of food for deer dUring months 

of heavy snow cover during the period when deer food supplies are 

generally at critically low ebb. Such sprouts are also of value 

as a winter food supply for rabbits and may in certain areas serve 

to divert rabbits from depredations on orchnrd stocks or other 

high-value species. In aquatic habitat such herbicides as 

Dalapon may be useful in elimination of cattail, which then is 

often followed qy·smartweed, a desirable food for waterfowl. 

l1any conservation agencies like ours carry on extensive farming 

operations on state-owned hunting lands to provide food for 

various forms of" wildlife. Herbicides may substitute for tillage 

on otherwise untillable land; they are helpful in clearing land 

of brush for intensive farming operations; and they may be helpfulin 

releasing' old plantings of food and cover shrubs from 

heavy sod development. We have tried Dalapon, TeA, and Amino 

triazole. It is obvious that in areas characterized qy extensive 

tracts of wilderness land, where access from the ground is· orten 

extremely difficult, the adaptability of herbicides to aerial 

application makes them a most promising tool. 

Fish. }IIanagement. In the management of inland sport fisheries aquatic 

vegetation often poses a difficult problem. There is a very real need for 

effective, inexpensive herbicides which will erodicate both algae and 

higher aquatic plants without posing a hazard to fish and other aquatic 

life, to livestock, and to humans.

23. 

AqUE.tic weed control can contribute to fisheries managernont in 

several ways: 

• 1. A consac erable body of experimental evidence indicates that 

in certain important aquatic situations greater fish production 

can be attained by favoring microscopic algae rather than 

submerged higher plants. 

2. Under-harvesting and over-population are serious problems in 

the management of many lake fisheries. Aquatic weeds afford 

shelter for young fish as well as for older, larger-size 

individuals. Eradication of all but a few isolated clumps of 

weeds serves to concentrate large fish from wide areas, and 

exposes small fish to more efficient predation. It seems 

likely, therefore, that aquatic weed control might be quite 

effective as a tool in the artificial manipu1E.tion of fish 

stocks. 

3. It is not uncommonto encoutner potentially productive lakes 

which are under-fished simply because weeds interfere with 

boats, propellers, and tackle. 

hipc.rian development of our inland waters foI' recreation has preceded 

at an explosive rate since the end of World War II. Interference of 

aquatic vegetation with boating, water-skiing, and bathing, presently 

accounts for more pressure on conservation agencies than does its deleterious 

effects on fish production. 

Yet, we find ourselves still turning to copper sulfate for local 

algae control and to sodium arsenite for the rooted aquatics even though 

the 11'.tter material, because. of its potentiel danger, is expensive in 

that the agency must supply personnel to insure proper treatment and to 

guard against risks. 

During the past year our fisheries research staff has conducted 

experiments involving use of pelletized 2,4-D applied over ice to control 

submerged weeds, and has attempted to control emergent vegetation with 

2,4,5,-T, Kuron, Silvex, and Dalapon. To date no success has been obtained 

with the 2,4-D pellets or with Kuron. Other tests will continue. 

Discussion: It will come as no news to those attending this confeI' 

ence that the use of herbicides often provokes hostility from sizeable 

segments of the general public. Conservation agencies are not immune to 

public criticism when they use herbicides, even though in the main they 

use them with greater care than certein other operators. For one thing, 

there is a ve~ general tendency for the public to confuse herbicides 

with highly toxic insecticides and to damn eve~thing that might fit under 

the general pesticide label indiscriminPtely. The greatest obstecle to 

the use of herbicides in chemical debarking has been the perverse refusal 

of most field crews to follow even the most basic and rudimenta~ 

instructions as regards application technique. My depar-tment, has not per-

mitted the use of sodium arsenite to debark standing pulpwood primarily 

for this reason: A few years ago, as an experiment, we authorized use 

of this m~terial on a small timber sale involving only about 120 acres. 

Elaborate preparations were made, including the plowing of a wide furrow 

ar-ound the tract to aid in detecting movements of deer into and out of 

the area, and most explicit instructions with regard to precautionary 

measures were made a part of the written permit. In spite of all these 

apparent safeguards and the certainty of detailed post-application 

inspection, the operators spilled arsenite liberally on the ground 

between the trees. And since .the job was undertaken rather late in the 

season, and ripening blueberries were affected, our people were actually 

more alarmed about the chances of killing Girl Scouts than about danger 

to wildlife. The experimental tract embraced a small lake, and at the 

public fishing site a rough table had been provided for cleaning fish. 

The operatolllSelected to clean their equipnent on the table and left it 

covered with chemical and with rags seturated with chemical. Twodeer 

were killed in this small plot and in view of the aggravated hazard 

also provided to humans our policy against the use of this material on 

state forests remains in effect. . 

Injudicious use of hormone-type herbicides, especially on highway 

rights-of-way, hps unnecessarily inflamed the public. County road 

commissions in particular are prone to use these materia~s without any 

advance explanation of how they IIl8Ybe expected to operate and how the 

taxpayer might ultimately benefit. ~ore important, operators seem 

inclined to keep the valve open all the we;ydown the roan, dosing 

individual trees and shrubs which might better be left intact, or perhaps 

even worse, hitting vegetation a glancing "lick" which results, not in a 

clean kill, but in an eyesore which dfends the traveling public and does 

not achieve the desired control. 

The last example cites a use not under the control of p censervatdon 

agency but you may rest assured that conservation agencies often are held 

"'r~ by the public. 

There is still considerable controversy as to whether the elimirultion 

of trees and woody shrubs along highway and powerline rights-of-way is 

injurious to WildlifE, using the term "wildlife" in its broadest sense to 

include songbirds and small mammals as well as game species. Here;·the 

answer probably depenrls in large part upon the amount of wildlife cover 

available in the adjacent coutryside. In a state such as Michigan, which 

generally has an abundance of wildlife

25. 

acreages dcs~rvinr treatment. 

In thJ pAst five years we have treated about 1),500 acres of game 

hnbitat with herbicides. Of this total, 11,000 acres were tree.ted from 

the air, 2,500 from the ground. This is a small figure, but that is 

because most of it has been experimental. Results still cannot be 

predicted with sufficient reliability to let us think of large scale 

trse.tment on a routine management basis. 

Further research is expecially needful in the field of aquatic 

herbicides. Aquatic biologists are inclined to feel put upon when they 

are asked to take hand-me-down chemice.ls developed for use in agrieultue 

and test them on aquatics in largely empirical fashion. At the bottom of 

a l?ke the soil-water interface is a dynamic area where chemical equilibrium 

requires constant change. Water movements are a constant, 

complic~ting factor. There is constant competition for light and nutrients 

between higher plants and phytoplankton. The rich be.cterial flora is 

continually degreding chemical compounds. The aquatic biologist has the 

additional problem of haVing to avoid significant damage to animal life, 

all the way from fish and fish food organisms to livestock and humans. 

Industrial research and development staffs would be improved by addition 

of someone competent in the chemical and physical aspects of limnolorY. 

Conservation agencies generally are not staffed to conduct research 

on the development of new materials. They are usually well equipped to 

test new products and techniques. As a representative of this field cr 

interest I hope thet a rehearsal of the potential uses for herbicides in 

conservation matters will stimul~.te the industry to keep our requirements 

in mind and to continue their search for products which will better meet 

our needs. 

Literature 

Cited 

(1) Arend, J. L. Control of undesirable h~rdwoods in forest 

management in the Lake States. Proceedings of the Tenth 

Annual Heeting, Northeastern Weed Control Conference, pp.34-36, 

January, 1956. 

(2) HcCulley, R. D. Forest l{anagement. In lake :.:tates Forest 

:Sxperiment Station Annual, Report for 1956. 60+ i-xi pp .• 

illus. (Processed) 1957. 

(3) Roe, E. I. Aerial brush control in the Lake States. Lake 

States Forest Exoeriment Station Miscellaneous Report No. 37 

9 pp. (Processed) 1955. 

(4) Rudolf, P. a., and R. F. Watt. Chemical control of brush and 

trees in the Lake States. Leke States Forest Experiment 

'Station Paper No. 41. 58 pp., illus. (Processed) 1956.

26. 

ECOLOGICALASPECTSOF ALLERGENICP:u.NTS 

The allergenic plants, for the purposes of this discussion, may be considered 

those which are normally harmless, blt which upon frequent and massive exposure, 

may become highly irritating to some people. In other words, the 

hayfever plants and poison ivy. V,lefrequently hear it stated that "the 

Indians had no hayf'ever." The statement was undoubtedly true and still is 

for those Indians who manage to l1vein something approximating their 

aboriginal environment; otherwise they can have hayf'ever just as we can. 

Poison ivy, on the ot.her hand was well lmown to the Indians and had a name 

in their tongues which translateci means "The plant which makes sores." 

Nobody cares much whether the Inci1ane had hayfever or ivy dermatitis, blt 

why they failed to have one and had the other is a matter of some ecological 

importance. 

Originally the North American Continent was fully occupied by stable 

associations of plants lmown to ecologists as climaxes, which is another 

name for culminations, so called because they represent the ends of long 

series of sorting out of plants 1ri relation to their environments. Every 

kind of environmental area became. fully occupied by the plants best suited, 

to it. As these areas ci1ffered in climate /10 they ci1f'fered in their climax 

associations. For example, most of Canada was covered by the Boreal forest, 

dominated by spruce, larch, firs, pines, birch and aspen. The Great Lakes 

region of southern Canada and northern United States was covered by the Lake 

Forest Climax, dominated by pines and hemlock, including the famed white-pine 

forest of Michigan, long since vanished. Most of the eastern part of the 

United States was occupied by the Deciduous Forest Climax, dominated by such 

trees as oak, maple, beech and chestnut. The interior of the United States 

was Grassland Climax, dominated by prairie grasses which have largely 

vanished with the buf'f'alo. The Pa~1tic Coast area was occupied by the Coast 

Forest Climax, dominated by such trees as cedar, hemlock, Douglas fir, 

larch and pine. . 

It is to be noticed that each of these climaxes was dominated by only a few 

species, those which had gained the ascendancy by being best titted to the 

condi tions prevailing over the larger part of the area. Besides these there 

were hundreds of recessive species which found themselves relegated to small 

and scattered areas where the so11 and moisture conditions were better suited 

to them than to the dominants. Among such were to be found most of our 

na ti ve weeds, including hayf'ever plants. They caused no haytever under 

these conditions because there were too few of them, occupying only small 

and scattered areas. But because of this they developed the habit of producing 

the huge quantities of pollen necessary to reach across the broad 

spaces usually intervening. 

Ragweeds, for example ,are lmown to be partial to disturbed so11; only such 

areas can they dominate, and such are rare in ecological climaxes. So they 

found themselves relegated to eroded river banks, nood plains and occasional 

erosion rills and gullies which under climax conditions are rare. flith the 

destruction ot most of the climax vegetation we have provided over large 

areas, conditions which they can dominate, and as we continue to disturb the 

soil we virtually create an artificial condition which can be called a

Disturbance Climax, since the maintaining factor is not the climate so much 

as the continuing disturbance. Disturbance Climaxes are known to have 

oc~urred naturally. For example, the short-grass prairies of the Great 

Plains are believed to have been a Disturbance Climax maintained by the 

grazing of buffalo. It was dominated by such plants as buffalo-grass, the 

grall!lll8s, bromes and fescue grasses which are notorious for being able to 

endure excessive grazing. Some are ,said to even benefit by being occasionally 

eaten down to their roots, something which their oompetitors were not able 

to endure. 

The balance between the grazing buffalo and the short-grass prairies lasted 

about 20,000 years, and all the time the soil was being deepened and enriched 

so that the prairie was self-perpetuating. Howdifferent is that from our 

artificially induced ragweed climax in which the disturbance causes the soils 

to be eroded and their nutrients leached away. It is self-destroying, and if 

not checked could very well spell the end of civilization, but probably not 

the end of hayfever because ragweed is curiously indifferent to top soil. 

This is the sermon that all conservationists have been preaching for years, 

but mostly to deaf ears. They ocoasionally take a look at our national bank 

account and, in the light of their studies,find it growing alarmingly low. 

The glorious achievements of civilization have been built on borrowed 

capital. Others of us take a look and discover a lot of assets there that 

we didn't know we had. These we rapidly convert into ambarrassing surpluses 

and laugh at the conservationist. The control of hayfever is a part of the 

much larger problem of conservation. Hayfever weeds find no more room under 

properly managed soil conditions than they did in the original climaxes. 

Ragweed is undoubtedly our most important cause of hayfever so it will be 

worth while to examine it closely to see what manner of plant it is and how 

it is so well able to take advantage of our current desire to shatter the 

earth to bits ~ remold it ~ to the heart's~. - 

Ragweeds are native American plants. All the true ragweeds, of which there 

are about 21 species, all potential hayfever plants, originated in the 

Americas. They belong to the great .Compositae or Sunflower Family which 

stands at the summit of the evolutionary development of the Flowering Plants. 

They and their near relatives make up a compact little group of plants of the 

utmost importance to hayfever students because they cause the greater part of 

the hayfever in North America. Of these the only ones with which we are 

concerned in the eastern states are the tall and short ragweeds. Botanically 

they are very similar and closely related, so much so that their pollens cross 

react almost interchangeably. But by their superficial characters they are 

easily told apart. The short ragweed has divided fern-like leaves, and is 

usually not more than four or five teet tall, while the tall ragweed has a 

less divided leaf, usually three or four parted or even undivided, and may 

be 10 or 15 feet tall, sometimes more. 

Both ragweeds are annuals and shallow rooted making their destruction easy, 

but a large .proportion of their seeds may remain dormant in the soil for 

many years, or until suitable conditions for their growth obtain, so that 

one weeding is never completely effective. Their seeds are characteristic 

27.

28. 

and easily recognized. They should be looked out for in seed grains. Each 

is enveloped in a fibrous coat which is the homologue of the involucre which 

surrounds the flower heads of other Compositae, for the female flower of 

ragweed is morphologically a one-flowered flower-head. The seed coat of the 

short ragweed is fragile and easily cast off. You may find thsir seeds in 

grains both with and without their outer coats. Not so the gi.arrt ragweed. 

Its seed is aquatic and designed to float on water. It is enclosed in a tough 

corky envelope which is difficult to remove. So much so that the seedling is 

provided with a special device for removing it, reminiscent of the egg-tooth 

on the beaks of some embryonic birds which they use to break out of their 

shells. When the seedling emerges from the ground the two cotyledons are 

generally partly enclosed in the seed coat which threatens to strangle the 

young plant. But it gets it off by wrapping itself around its own stem 

which is provided with a ridge into which the flairing tip of the seed coat 

is hooked and pulled off, leaving the seedling free to expand its cotyledons 

to the sunshine. 

Ragweed is generally described as an 'unsightly weed.' This is purely subjective, 

an emotional response due to causes other than its appearance. It 

is wind pollinated so does not have attractive flowers and, as is usual with 

such flowers, has the sexes separated. The staminate or pollen-bearing 

flowers are borne in little heads in terminal spikes. They are very numerous 

and each head contains 1..5to 20 little flowers. Though these flowers are 

entirely male and produce no seeds, the pistil is retained for its secondary 

function of forcing the pollen out of the flower, characteristic of the 

Composite family, even those with fertile pistils. 

V:hat has been said of the short ragweed applies almost equally to the giant. 

The two can generally be found competing with each other for waste places. 

The flowering spikes of the tall ragweed are larger and produce more pollen 

than those of the short. I once estimated that a single spike would produce 

6 million pollen grains. And they say it takes only 25 grains per cubic 

yard of air to cause a sensitive person to sneeze. 

Ragweed pollen grains are spherical, about 17 microns in diameter, which is 

unusually small among pollen grains. The outer coat is thick of a deep yellow 

color, tough and provided with three or occasionally four germ pores through 

which the pollen tube may emerge at time of fertilization. The outer coat is 

also provided with low conical spines which add greatly to its surface area. 

This and its small size account for the grain's extreme buoyancy and range of 

flight. 

Short ragweed has a surprisingly wide distribution. It ranges from Nova 

Scotia southward to Key ~est in Florida, and even to the islands of the 

Caribbean sea, and from the Atlantic coast westward to the foothills of Us 

Rocky Mountains, and even beyond though not in effective quantity. Its 

place there is taken by the western ragweed which is very much the same, 

except that it is perennial, spreading by underground stolons as well as by 

seeds. Short ragweed grows in all types of soil that can support vegetation, 

and even some that otherwise can not.

Tall ragweed has a more restricted distribution. It is scarcely found north 

of the Canadian border nor south of Georgia and is not found much east of the 

Connecticut river. It is less hardy, less versatile than tm short ragweed 

and more partial to moisture. 

The ragweeds are notable for flowering always at the same time in the same 

place, regardless of weather or other influences. In the NewYork area the 

time is about the 20th of August. At least that is when the plants reach a 

stage of flowering profuse enough to start haytever. Further north they 

flower earlier, about the 1st of August in Nova Scotia. But farther south 

they flower later, and the farther south they grow, within certain limits, 

the later they flower. Along the Gulf coast it is well into September 

before they reach the hayfever-producing stage. 

This precision of flowering with only latitudinal variation is not unique. 

Asters, marigolds, chrysanthemums and other late-summer plants do it too. 

In fact there is a whole group which are known as short-day plants because 

it is the shortening of tm days in the late summer that stimulates them to 

stop growing and begin to flower; it is their warning of approaching frost. 

This can easily be demonstrated by giving the plants a few extra hours of 

artificial light as the natural daylight begins to shorten. An ordinary 

electric lamp is enough, turned on fora few hours just as it begins to get 

dark. But it is not necessary to take even this trouble because the 

experiment is being done far us under the street lamps in mostly any town. 

I once watched from day to day a clump of tall ragweed and another of short 

growing under street lamps in New York City. All the weeds beyond the 

influence of the light, about 18 feet, flowered at the appointed time, and 

by the end of September had ripened their seeds and the plants were dead and 

dried up. Not so those under the street lamps. All through october the 

weeds continued to grow, becoming much taller than those beyond the range of 

the lights, but they did not flower. When the first killing frost arrived 

on the 11th of November they were still green and with the flower buds 

beginning to show. So we see that it is not the frost, as frequently stated, 

that terminates the ragweed season. It is the frost-warning of the 

shortening days that does it some weeks before the killing frost arrives. 

Artificial shortening of the days has the opposite effect. Early one spring, 

about the middle of May, I selected a dozen seedlings of short ragweed all 

about the same size. These were potted. Six were moved into a dark room 

every evening at five o'clock and out again at 9 in the morning. The other 

six were allowed to enjoy normal daylight. The plants which were treated tC' 

artificially shortened days stopped growing immediately, developing flower 

heads instead, and by the end of June were in full bloom shedding normal 

pollen which was shown by skin test to be capable of producing hayfever. 

The control plants had grown several feet in the meantime but showed no signs 

of flowering. The same experiment was tried with tall ragweed, with 

essentially the same results, except that the treated plants did not cease 

growing in height. They grew as tall as the controls but spindly without 

branching and came into flower at the same time as the short ragweeds. 

29.

30. 

Because the ragweeds accept the shortening days as the frost warning, and are 

unable to flower until it is received, they are restricted in their northward 

range and in elevation, and that is why the VJhite Mountains and northern 

Canada are good hayfever resorts. The season of far northern latitudes and 

high elevations starts too late and ends too early for them to complete their 

growth. In Nova Scotia the ragweeds never grow tall. They get a late start, 

because spring comes late there, and they are forced to £lower early because 

the short days come early, so we find them only about knee-high. In the south 

the ragweeds grow tall because they start early and have a long season to grow 

before they get the frost-warning which in the south comes late. 

This is the way the ragweeds behave throughout the regions of winter frosts. 

This reaction to day-length enables the plants to take advantage of the full 

growing season, whether it be long or short. But this is not the whole story. 

The ragweeds which grow far south, beyond the range of killing frosts, £lower 

almost throughout the year. In Miami, Coral Gables and Key West, for example, 

short ragweed may be found in all stages of development in March and April. 

Young seedlings may be growing beside mature plants ripening their seeds. 

The same is true in Cuba. South of the frost line the ragweeds behave like 

most other plants in tropical regions, in total disregard of the lengthening 

or shortening of the days. ~Ihy not? Vfhy heed the frost-warning where frost 

never comes? 

Howcan these plants adapt themselves to climates ranging from the cold of 

Nova Scotia to the heat of Cuba? Howcan they be so sensitive to day lengths 

throughout the northern part of their range and abruptly cease to respond 

when they find themselves south of winter frosts? The explanation is that 

short ragweed is a complex and variable species, consisting of a number of 

genotypes which under natural conditions tend to segregate out. These are 

not different species, though sometimes considered so, because they may be 

recognized among the progeny of a single plant. One of these segregates is 

the southern strain which ignores the frost-warning. 'V;henever it makes its 

appearance in the North it finds itself at a disadvantage so succumbs to the 

competition of others with better adjusted economy, but in the South this 

characteristic has real survival value. 

The fact that short ragweed consists of many races which may be sorted out to 

suit any clime or situation explains its enormous geographic range and 

adaptability. Just as we can breed a dog for any purpose nature can breed a 

ragweed to suit any soil or climate. 

Certainly ragweed is a successful plant and well able to adapt itself to a 

variety of conditions, but the question is: What good is it? This can best 

be answered by going back to its ecological aspects. It belongs to a group 

of hardy pioneers which playa very small role in the climax communities, but 

once the climax is lost it could never be regained vlithout them. 

From the ecological standpoint the climax is the most desirable association. 

It permits the largest number of plants to grow under the most sui table conditions, 

that is the greatest good to the greatest number.

The climax is the culmination of a long series of steps, known as the 

Ecological Success~on. The story starts with such barren beginnings as bare 

rock or a fresh-water pond, plus a few lichens or simple water weeds. These 

slowly and painfully, through their growth and decay, accumulate a little 

soil. Their only reward is that it enables higher plants to successfully 

complete with and dispossess them. These in turn accunmlate more soil 

enabling still higher plants to complete with them, the lowly always giving 

way to the more advanced as soil conditions improve. The succession is a 

dramatic story of the struggle of plants for their existence, often winning 

or losing by the narrowest of possible margins, but the story is too long 

and involved for us to follow through here. We will skip a few millenia and 

assume that we have soil enough to support the elimax vegetation, but that 

it has all been removed and the soil abandoned, which is the stage in vlhich 

we are most concerned. The rains come, the w.l.nds QIOl'land the unprotected 

soil begins to be washed or blovm away and its soluble nutrients leached out. 

Long before the climax vegetation could be reestablished the soil would all 

be gone and we would be back to the bare rock or empty pond, stage, were it 

not for the fast growing pioneer weeds which move in. Before the 

destruction oc.curred we may never have noticed them but they are always 

there on their seeds lying dormant in the soil. The destruction of the 

climax vegetation is the awakening kiss that breaks the magic spell of their 

slumber. This 18 ,their long awaited opportunity. All over the denuded area 

they spring into life,and in a single season may occupy the area and hold 

the soil against the rains and wind. These plants are all annuals, shallow 

rooted and fast growing. They are known to the ecologist as pioneers; they 

make up the Pioneer-Vieed Stage in the ecological succession. They are such 

plants as wild nmstard, the pigweeds, carelessweed, ~ambsquarters, marsh 

elder, cocklebur , Russian thistle and the ragweeds. Most of them are wind 

pollinated, for they move too fast to wait for even the rapid breeding habits 

of insects to provide enough individuals for their pollination. Foremost 

among them are the ragweeds. The important role tbltthey play in saving the 

soil answers our question regarding their usefulness. The huge quantity of 

pollen which each plant had to disselll:inate when growing at wide and scattered 

intervals is now no longer necessary; most of it is surplus, and always it is 

surplus pollell that causes hayfever. However it is essential to these plants 

to have it in"reserve for their lush times are soon over unless the 

disturbance .that released them is continued. For, in the ordinary course of 

events, the Pioneer-V/eed Stage lasts only two or three years, seldom more 

than five, because, by stat1lizing and enriching the soil the pioneers prepare 

it for their more robust competitors such as the perennial weeds and grasses. 

So the Pioneer-Vieed Stage gives way the tate-Weed and Grass Stage. It is a 

society principally of grasses, the agricultural grasses and numerous others 

together wi thsuch weeds as plantains, docks, dandelion and clovers. They 

are mostly deep-rooted perennials which gives them the advantage which they 

need to usurp the pioneered areas. It is an easy stage to render permanent 

by grazing or cutting, maintaining it as a Disturbance Climax. For example, 

a cow- or sheep-pasture, a hayfield, a golf course, a playground or a lawn 

are all ecologically alate-weed and grass disturbance climax. There is no 

hayfever and little poison ivy in it, and it can always pay for its keep and 

return a substantial profit requiring only to be properly grazed or cut, and all 

the time it builds humus. It ~s by far the most economical condition t? keep 

4'-_ , , ~__ _ '1.0 •• 

31.

32. 

recjuired. Left to itself. however, woody plants tind conditions favorable and 

invade from ac\Jacent areas by rhizomes. Snowberries, sumac, poison ivy, 

brambles, cat briers and, other' shrubs- shade out the @rasses and weeds, 

inaugurating the Shrub Stage. The Shrub Stage is nearly useless, except far 

occasional raspberries, blueberries and elderberries. It is difficult to 

plough and. what ,is important to us, it harbors most 'Of the poison ivy and, 

in ewampyplaces, poison sWllll.c. The only good thing,abouti1:. is that, left 

to itself. it is gradually taken O'V\!lrby trees, and 80 goes back to the climax 

forest. 

Poison ivy (RhUSradicans) J POiS~ oak (R. Toxicodendron) and Poison sumac 

(R. Vernix) aI1'1er In every way from ragweed.' They belong to the Cashew 

faiD:l.!Y"1Anacardiaceae) as does the ,familiar cashew nut. It is a large family 

of trees and shrubs. mainlytropj,cal~ Many of them oarry the same or similar 

vesicant substance. The cashew nut. of oourse, is free from it. butthe1r 

shells contain it in large amounts. 

The vesicant substance of the poison ivy has been identified. It consists of 

four related substances, phenolicdel"ivatives known as catechols, that is to 

say chemically related to phenol or carbolic acid. They have been isolated 

and two of them synthesised .1!hey are solids, ,insoluble in water. soluble in 

oils. alcohol and. acetone. 'All :a.re vesicant in varying degree. It appears . 

that the ~fferent specles which have this sU.bBtancepossess the four 

componEllttsindifferent proportl ons, or may lack one or more. whlchprobably 

explains their wide.,variaU:on in toxicity. It is well known that some of the 

tropical species are much more toxic than ours. 

Poison ivy reaches its best deV~loP/18nt in the Shrub Stage. V1henwe see it 

on stone walls, climbing tences'~ l:Ibrubs and small trees -or even form1ng 

thickets of its own.,1'1;is at Us. best and f'orlDBan·-important part of its 

ecological stage. ~Un1ike ragweed., however, it also. takes a more or less 

prominent part inlllOs.t other s.tagee. of the succeseion;even in the Climax . 

Forest we occasionally see it clilllb1.ng to the toPS ot,talltrees. That is 

why the Indians had poison-ivy dermatitis and knew the ivy as' the plant"'"thlil.tmakes-soreS 

long before 1twas seen by white man. It is least prominent in 

the Late-freed and Grass Stage •.. St111 it is not safe. to go bare ..toot through 

a pasture. a hayfield or even a lawn.tor .it may-be there too, even if you 

don't see it. Fortunately it can be controlled by hormone sprays, and, as 

far as I know, that is the on~yw:ay. 

What we.can learn from this .cursory examination of the ecological aspects ot 

allergenic pl~ts 1sbestsUrmiedupin.the words of Pau~ Sears who says, in 

Deserts on the March, "Nature will not to~erate id1esurface on the earth, 

and She is not to be conQuered save on her own terms." 

Roger,p. llJodehouse, Ph. D. 

Orangebl!r gRoad 

Pearl ~ver. N. Y. 

November 19, 1958

33. 

viEW L:ONTROLIN SOUTHJRIC .... 

by 

LR. Hattingh 

.Hric;an ExpL.lsi ves end Chem.Lca) InJustrie::, 

Johannesburg. 

'l'be grEater part of the Orii on of South Africa 

l~e~ between the tropic of Capricorn and 34°S, and 

although the latter latitude is generally taken as 

the limit for subtropical climates, the high 

~ltitude of interior plateau (Highveld) makes for 

a temperate type of climate over a wide area. 

Climatic variations give rise to five distinct 

ecological zones which in turn determine the type 

of agriculture and weed problem encountered. 

These zones are Fynbos (winter r~infall Macchia or 

Chapperal type); Forest; Karoo (steppe); 

Grasslands and Bushveld (Woodland). 

Only 8% of the total land surface is unde~ 

cultivation. Of this area, 6.4% or 18 millior 

acres are cul tivated by Europeans, and 45% of '.rl .. S 

area (8 million acres) are under maize. Ther~ 

are 110,000 farmers, one third of whom are e:n r '''ed 

in commercial maize production (1). Weed ccr.trol 

in maize is therefore important. 

Wheat is the second most extensive arable 

crop, and is grown both in the winter rainfall 

area &nd summer rainfall areas - in the latter by 

means of summer fallowing. During 1954/55, nearly 

3 million acres of wheat were grown. 

Other field crops such as groundnuts, field 

beans, sunflower, potatoes and sorghum are grown, 

but are of minor importance compared to wheat and 

maize. 

Sugar cane is an important crop in the 

Union, and is grown in the SUbtropical coastal 

zone of Natal on the eastern sea board. Almost 

500,000 acres were under cultivation in 1955 (2). 

/Contd •••••.

34. 

The greater part of the farmed area of 

:3outh Africa is utilised for pasturage of sheep 

or cattle, and it is in this region that many of 

our major problems lie. 

WEEDCONTROLIN '{lHEAT 

In the winter rainfall area, wild vetch 

Vicia atropurpure~ and other species, together with 

Rapharuls raphabistrum, are the most widespread weeds. 

Because of the waterlogged fields, aerial 

application of herbicides is necessary. 2,4-D 

ester in an oil carrier at i-lb. acid equiv. per 

acre is usually applied. There is no evidence 

that control of these weeds increases yields, or 

that the best control method is being used. 

About 200,000 acres are treated annually. A 

number of weeds resistant to 2,4-D at the usual 

rate of application appear to be increasing. 

These are Emex australis. Reseda sPP, and Silen0 

..§1U?. 

In the summer rainfall areas, discing is 

used to maintain a bare fallow for sevcr81 months 

prior to autumn seeding of the crop. The weed 

problem occurs from very early spring to late 

spring, and consists of Polygonum aViculare, 

Polygonum convolvulus, Rumex angiocarpus and 

Chenopodium albu."'1. 2,4-D amine, or 2,4-D ester 

at i-l lb. acid equiv. per acre is applied either 

from the ground or air. 

The culture of wheat in spring and summer is 

being undertaken and where this is so, the control 

of annual, grasses which emerge with thf' crop, is 

the major problem. 

WEEDCONTROLIN MAIZE 

The weed problem consists of annu21 gr2ss2s 

such as Eleusine indica; and Panicum lac;vifolum, thE' 

sedge, Cyperus esculentus and broadle~ved weeds 

such as Datura stramonium, D. ferox, Amaranthus 

paniculatus, and Xanthium pungens. 

/Contd •••••

jContd ••.•. 

There is no doubt the. t weeds r.r e very 

dapressing to the yield of maize under our 

~onditions, and our low average yields (3.5 

bags of 200 lb. per acre) are attributable to 

poor weed control arrlongst other factors. It 

has been shown in an experiment at Rietvlei (3) 

that unfertilized, weedy maize yielded 3.05 bag5 

compared to 9.33 bags from unfertilized but weed 

free maize. When fertilized, the yield incre~sed 

to 15.7 bags under weed free conditions, but 

with no weed control the crop yielded only 8.05 bag~ 

r:lther less, but not significantly so, than the 

yield obtained from unfertilized but weed free 

maiZE. 

1\.S to the actual time of most acut~ 

compet I Han, Marais (4) has shown that the greatest 

reductions in yield occur by weed competition 

during the second month after planting. Weed 

control operations should be ~imed at securing 

~ weed free crop during this period. 

Field experiments conducted by A.E.&.C.I. 

over a number of years (5,6) clearly show the 

depressing effect of weeds on maize, and the 

increases obtained from pre-emergence application3 

of I-lb. 2,4-D or MCPAper acre. I-lb. of 

selective weedkiller, combined with one or two 

subsequent cultivations, is normally sufficient 

to produce yields equivalent to thnt of continuously 

weeded maize. 

At pr0sent, 1-2 Ibs. of MCPAor 2,4-D is 

usually applied shortly after planting. Thu 

period of control obtained is 3-6 weeks. It is 

desirable th"t this period be extended, especially 

over the r-ov, and exp er-Iment s ar e in progress to 

determine wh8ther this can be economically 

~chieved using the newer herbicides. 

Post emergence control of broadlcDved w8ed~ 

is undertaken, but because of the possihility of 

injury, actual application is restricted to the 

3-4 leaf stage of growth using cover sprays, or tv 

the taller stages using directed sprays. Witchwecd 

(Striga asiatica) is a problem in the warmer ar c.;s , 

and is controlled by me2ns of post emergence spot 

spraying using 2,4-D or MCPA.

36. 

--/ 

WEEDCO~TROL 

IN SUGARCAN~ 

Cyperus e6culentus, Eleusine indica, P&nicum 

EQQ, wad broadleaved weeds are the problem. As 

many of these weeds emerge before the cane, contact 

pre-emergence or residual, or a combination 

may be used. 1iher~ annual grasses are the problem, 

2-4 Ibs. MCPAor 2,4-D may be applied immediately 

t.fter planting, but where nutgrass is the problem 

c:..pplication may be delayed and a combt.nct.t on of 

2,4-D 0nd 5%PCP applied, any time up to the flag 

stage. 

After tae flag stage where nutgrass is 

troublesome, 5% PCP at 4-5 gallons per acre or 

TCA at 15-lbs. per acre is used. On a cost: 

efficiency basis, Da.lapon is uncompe't Lt.Lve ?t 

pr e serrt , 

Due to the steep topography, all app Lf cr.t.Lon 

is made by hand using knap sack sprayers. 

WEEDCONTROLIN PASTURES 

In the Bushvcld (Woodland) arens, c~tt18 

ranching is the main activity. Because of an 

unbalance in the grazing system, the succession 

has been accelerated towards a thicket type of 

foxmntion, at the expense of the grass species. 

This has considerably lowered the carrying capacity 

of the veld. Overgrazing, combined with the 

exclusion of fire, has been the main contributory 

factor. Invading species are mainly thorny - 

Ace-cic:.karroo; A. Heteracantha (= tortillh); 

A. arabien; A. detinens and Dichrostachys glomcrata. 

Non-thorny species such as Euc102 sp and 

Tarchonanthus 3p 3re also trOUblesome. Over 

40,000 squar-e mil es in Transva

37. 

lkrbici.des are rb1u.i.TE':d, hut IIp to tLE:: 

pr-e ser.t , u sef'u L r esul.t s have no t beau obt af.ned , 

.xc cot in Loc aLi sed areas. In many c a s es , diesel 

,;U :1.l("lYlE' appear s Satisfactory (9). Consistent 

results with 2,4,5-T, either as basal or overall 

spray~ have not been obtained, and the problem is 

far from solved. 

Jointed cactus (Opuntia aurantiaca) haS 

invaded over 2 million acres in the Eastern Cape 

Province. Work undertaken by the Department of 

Agriculture has led to a national campaign using 

2,4,5-T butyl ester in illuminating paraffin. 

Slangbos (Stoebe vulgaris) is «n invader of 

grassland, and may be controlled by using2,4-D 

ester or by burning in early summer. 

GENERAL 

In general, weed control in South Africa 

receives insufficient attention both from the 

research and advisory sides, and itslmportcrc~ 

is not sufficiently understood by th~ average 

farmer. Contact with weed workers in the 

United States has helped in the past ,!Od the 

privilege of attendj~~ your conferences and 

visiting your resesrch centres will be of gre~t 

value to us in South Africa for the future.

38. 

REFERENCE 

(L) M0d L. Industry Control B03.rd Annuc.I 

Report 1957 - Union of South Afric~. 

(n South Africa t:iugar Journal, Februnr-y 1957. 

(,) Hhitmorc, '],,3.; Marais, J.N.; and 

H. H. 'I'ur-p Ln : "Weeds, a H3.jor Menac~ to 

Crop Production". Farming in Soutt Afric:. 

28 September 1953. 

(") i11'.r

1 Graduate student and Assistant Professor, respectively, Department 

of Botany, Ontario Agricultural College, Guelph, Ontario. 

2 The abbreviations Rand S will be used throughout this paper to 

T'Af'AT' T.n ? J._n 1"'0 cd QT.!:!"+-. !:lnn a.11QI"o",,+-.;n.lo C! ...._,....~; ..... a 

STUDIESONTHEDIFFERENTIALRESPONSEOF STRAINSOF 

WILDCARROTO 2,4-D. 

Charles W. Whitehead and Clayton M. Switzer l 

Strains of Wild Carrot exhibiting marked differences in response 

to 2,4-D wer~ reported in an earlier paper (4). In ~orphology and 

growth habits the susceptible (S)2 and resistant (R) strains were 

similar, as they were in their physiological reaction to 2,4 5-T. It 

appeared, therefore, that a study of the physiological basis'ror this 

differential response might provide an important new approach to the. 

problem of the mechanism of 2,4-D selectivity. 

Methods and Results 

Several avenues of investigation were explored in this study in 

order to characterize the differential response fully and help discover· 

its physiological basis. These included overall spray treatments, 

soil applications, seed germination and radicle growth studies, 

and effects on respiration. 

Overall Spray Treatments - Seeds of Sand R strains were germinated 

in flats and transplanted to 3-inch pots when they had 2 true leaves. 

Five plants of each strain were sprayed with each solution being 

tested.when they were 6-$ inches in height (5-$ leaves). Each experiment 

was replicated twice. 

. 'I'he butoXy ethanol' ester, sodium salt and amine salt of 2,4-tJ, 

4,MCPBbutyl ester, 4-2,4-DB butyl ester, 2,4,5-T isooctyl ester and 

Silvex (2,4,5-TP) were tested at various concentrations. Sufficient 

spray material was applied to thoroughly wet all above-ground portions 

of the plants. Data on percentage kill, determined at the end of 

6 weeks, is presented 'in Table 1. 

Table 1 - Herbicidal Effects of Various Chemicals on 2,4-D 

Suacept fb Le and Resistant Wild Carrot Plants 

%of Treated Plants Killed* 

39. 

Treatment 

2j4-D - Na salt 

2j4-D - am'Lne 

2,4~D ~L.V. ester 

4-2,4-0B** 

4..MCPB** 

2,4,5-T 

Silvex** 

S 

60 

$0 

70 $0 

100 

100 

100 

R 

o 

10 

20o 

20 

100 

100 

*Counted 6 weeks after treatment 

** 2000 ppm - all others used at 1500 ppm.

40. 

Most S plants were killed by all of the chemicals tested but only 

2,4,5-T and Silvex were equally toxic to Sand R plants. All treatments 

brought about typical auxin-herbicide symptoms of about equal 

severity soon after application. Within one week, however, the R 

plants, except those treated with2,4,5-T and Silvex,' had begun to 

recover. This recovery was marked by the growth of new leaves which 

showed no herbicide effects, and by failure of the treated leaves to 

become chlorotic. 

ABalication of Herbicide Through the Soil - The possibility was con 

S1 ered that the difference between S and R plants might be connected 

with their ability to trans10cate herbicide from the leaves LO the 

crown. Cons~quent1y, 2,4-D was applied both on the surface and 

beneath the surface of soil in which well developed Wild Carrot 

plants were growing. In the former treatment, 10 ml. of a 2000 ppm 

so:ution of 2,4-D amine were pipetted into depressions in the soil 

surface surrounding the plant, taking care to keep it away from the 

crown. The sub-surface applications were made by pouring 10 ml. of 

the same solution through a glass tube which had been placed 1 - 1.5 

inches into the soil near the root. 

Similar responses to those brought about by spraying the leaves 

were obtained in the soil surface treatment. Characteristic 2,4-D 

symptoms developed in both Sand R plants, with theR plants 

"growing out" of the effect within a few weeks. However, when the 

herbicide was applied below the soil surface, 40% of the R plants 

failed to recover. Evidently the placement of this high concentration 

of 2,4-D close to the roots resulted in near lethal levels of 

chemical accumulating in the cells. Nevertheless, this experiment 

indicates that the difference in 2,4-D effect on Sand R plants is 

not influenced to a majmr extent by differences in absorption by 

leaves or translocation from leaves to crown. 

Seed germination experiments - The germination of seeds of resistant 

species (oats, barley, ry~) has been shown to be not as severely 

inhibited as that of susceptible species ..(yellow, charlock, plantain) 

(5). It was considered that information of a similar nature for 

seeds from Sand R Wild Carrot plants would be of value. Seeds of 

each strain were placed in petri plates on filter paper moistened 

with the sodium salt of 2,4-D at concentrations of 10,25,50,100, 

200,300,400, and 500 ppm. Counts were made of germinated seeds 

after 7-8 days and expressed as percentage of control. 

Concentrations of 2,4-D above 100 ppm markedly inhibited 

germination of both Sand R seeds (50% inhibition at 200 ppm) with 

no consistent difference bwtween the reaction of the two types. 

Apparently the resistance of the R strain to this herbicide differs 

from that of grasses in this respect. 

In a further attempt to learn more about the' response of Wild 

Carrot plants to 2,4-D early in their development, experiments on 

the effects of ther herbicide on radicle elongation were carried out.

The technique was the same as in the germination study except that 

lower concentrations of 2,4-D were used (from .005 to u1.0 ppm) and 

growth was allowed to proceed for one week after germination. The 

results of a representative experiment of this type (Table 2) 

indicates that, as with seed germination, there is no different in 

the response of the two strains to 2,4-D at thissaage of plant 

development. Growth in each case was stimulated by 0.001 ppm and 

progressively inhibited at higher concentrations. 

Table 2 - Effect of 2,4-D on the growth 6f radicle of Sand R 

Wild Carrot Plants 

Length pf Radicle (mm)* 

Concentration of 2,4-D (ppm. ) S R 

0.0 7.1 8.9 

0.0005 7.6 7.1 

0.001 9.9 11.3 

0.005 5.9 5.9 

0.01 4.9 4.7 

0.1 1.9 1.9 

1.0 1.5 1.3 

* Average of 20 radicles measured one week after germination. 

Since well developed plants of Sand R strains (5-8 leaves) 

show differential responses to 2,4-D, but germinating seeds do not, 

at least as expressed by radicle elongation, it would seem that the 

resistance must develbp between these two stages of growth. In an 

effort to establish more closely the time at which such resistance 

first occurs, seedlings of both strains were sprayed with herbicide 

soon after emergence (when first true-leaf was barely visible). 

Concentrations of 25,50,100 and 200 ppm of 2 4-D amine were applied 

to counted Sand R ~eedlings in flats tapprox. 100 per flat). 

The percentage of plants killed by the various treatments was 

determined :six weeks later. 

Data from this experiment, present~d in Table 4, show that a 

marked different in response to 2,4-D is exhibited by the two 

strains. Evidently the factor or factors making some Wild Carrot 

plants re sf.scant , i.~ present in the cotyledon stage. Whether this" 

factor develops in the short period of time between radicle elongation 

and cotyledon expansion, or simply was not shown up in the 

41.

42. 

germination experiments has not been determined. 

Table 4 - Effec~s of low concentrations of 2,4-D on Sand R 

Wild Carrot Seedlings 

%of treated plants killed· * 

Concentration 

25 

50 

100 

200 

of 2.4_ u (ppm) 

* Calculated 6 weeks after treatment. 

ResEiration Studies -The possibility was considered that metabolic 

difference s could exist between Sand R plants -that might account for 

ttre differential response to 2,4-D. Respiration is an easily measured 

part·of plant metabolism and it is a part that is markedly influenced 

by 2,4-D (2). ·Of particular interest is the fact that respiratory 

responses to ·2,4-D have been shown by Kelly and Avery (1) to differ 

between susceptible (pea) and resistant (oat) plants. Therefore, 

experiments were set-up to compare respiration of Sand R plants 

under various treatments. 

In vitro measurements of oxygen uptake by root slices and leaf 

sections were made in a conventional Warburg respirometer •• The body 

of each-flask contained tissue', O.lM buffer (KH2P0T.' -Na 2HP0 

(pH5.5) 

and 2,4-D (sodium salt)." Pressure changes werere~ordel1 at 4) 5 minute 

intervals for 30 minutes, then at one-hour intervals for 3 hours. 

Duplicate flasks were used in each experiment, and each experiment 

was replicated 3 times. 

The results presented in Table 5 show that 2,4-D stimulated 

S 

62 

59 

49 

98 

R 

9 

3 

7 

27 

Table 5 - Respiration responses of Wild Carrot Tissue to in vitro 

treatments with 2,4-D. 

Oxygen Uptake 

(% control) 

Concentration of 2,4-D(M) S";leaves S-roots R-leaves R-roots 

Control 100 100 100 100 

1(}..5 113 121 

10-4 112 113 103 109 

lQ...3 85 103 83 98 

10-2 63 61 59 70

43. 

oxygen uptake of both leaf and stem tissue at low concentrations 

and depressed it at higher rates. Leaf tissue appear-ed to be 

slightly more sensitive to· the herbicide as lO~3M inhibited oxygen 

uptake about 15%. However, there were no differences between S 

and R tissues in their re~piratory response. Therefore, these 

in vitro tests seem to Rhn.wthat the factor for resistance is 

not one connected with respiratory metabolism of'2,4-D by the 

R plants. However, other tests, now in progress~ indicate 

that some respiratory differences may exist in vivo. 

Discussion 

snd Conclusions 

The selective herbicidal action of 2,4-D has been related 

to several factors (2). Differences in leaf surface, leaf . 

arrangement, accessibility of growing point to applied spray, 

absorption, translocation, adsorption on inactive sites or other 

detoxification reactions may regulate the degree of susceptibility 

and resis~ant strains within only one species, the first three of 

these possible explanations for the differential response may be 

discounted, In addition our studies indicate that differences 

in absorption, translocation and respiratory metabolism are 

small. It would appear, then, that the resistant strain of 

Wild Carrot may possess some 2,4-D detoxification mechanism such as 

that suggested by Leopold (3) which is not possessed by the 

susceptible plants. Such a mechanism would haye to be specific 

for the 2,4-D type of herbicide as it has been shown that the 

reststant plants are killed by the closely related chemicals, 

2,4y5-T and Silvex. Further studies on the exact nature of 

this detoxification are being carried on. 

Literature 

Cited 

1. Kelly, Sally, and Avery G.S.Jr. The effect of 2,4-D acid and 

other physiologically active substances on respiration. 

Am. Jour. Bot. 36: 421-426, 1949. 

2. Leopold, A. C. Auxins and Plant Growth. (University of 

California Press, Berkeley and Los Angeles (1955). 

3. Leopold, A.C. The fate of 2,4-D in plants and soils. 

Proc. North Central Weed Control Conference 13: 4,1956.

44. 

4. Switzer, C. M. The existence of 2,4-D - resistant strains of 

Wild Carrot. Proc , Northeastern 1\Tcled Control Conference 11: 

315-318, 1957. 

5. Templeman, W. G. and Sexton, W. A. The differential effects of 

snythetic plant growth substances and other compounds upon plant 

species I. Seed germination and early growth responses to 

a-naphthylacetic acid and compounds of :the general formula aryl 

OCH 2 COOR.Proc. of the Royal Society B.133: 300-313, 1946. 

Acknowledgement 

A fellowship grant from the Dominion Rubber Company, to the 

senior ,author, is gratefully acknowledged.

The peas trer-e SOVJIl in reV'TSspaced 7 inches a;Jart at the standard 

rate used by the grover-a in each ar-ea for cannfng peas , 'It :~te. Clothilde 

they wer-e planted on :,pril 24, 1957, and ;;ay 5, 1955. Planting took place 

Ilt Smithfield on :.pril 27, 1958, and on April 23, 1958. The herbicides were 

applied at Ste~ Clothilde with a boom, sprayer mounted on an Allis Chalmers 

G tractor. .\. pressure of 70 psi delivered by a nylon roller pump was used, 

,..t Smithfield they irer e applied with a boom mounted on a small garden tractor 

using a pressure of 30 psi~ 'The experimental desiens used in both years 

wer-e the latin square at ~thfield and randomized blocks at Ste. Clothilde. 

In addition, a s:)lit plot design ilith four replications ~IaS used. for testing 

the action of ;:CPB on different varieties of canning peas at Ste. Clothilde 

in 1958. Theplot size used. at 3te. Clothilde in 1957 was 1:121 of an acre 

and in 1958 it was 1:182 of an acre. "t Smithfield the -clot size was 1:210 

of an acre in 1957 and 1:260 of an acre in 1958. All po~-emergence treatments 

I'Tere applied. ~lhen the peas were ap:)roximately 4 to 5 inches tall. As 

nearly as possible treed counts wer-e taken 3 weeks ,after treatment. They 

""ere obtained from 4 random'square foot areas in each plot at 3te. Clothilde 

and 6 random ecuar e foot areas 'in each plot at 3mithfield. 

45. 

"- 

THEEFF":'CTSOF PHENO..... "YBtJTril.ICACID D::aIV:...TIV";S 

ON C;.NNINGP;;;;,S III SOliE AreAS OF CAllADA 

J. J. Jasmin, VI. J. Saidak and L. H. Lyall 

The herbicidal activities of a number of substituted gamma 

(phenoxy ) butyric acids were evaluated by Uain (5) worl:ing in the United 

::ingdom. Further reports on the selective herbicidal action in crops of 

gamma (4-ch10ro-2-methy 1phenoxy) butyric acid ~;CrB) and ganma (2, 4-dichlorophenoxy) 

butyric acid (2,4-DB) were published by \lain (6), Carpenter 

and Soundy (1) and other ~glish workers. Fryer and Chancellor (2) have 

shown that the lethal action of l·X:PBand 2,4-DB equal.e or surpasses that of 

;lOPAor 2,4-D for certain "Teed species. They also noted that J.IC?Bwas almost 

as tccd.c as l:CP•• when applied. to Canada thistle, prickly annual sow 

thistle vTi1d buckwheat, lady1s thumb, creeping buttercup and curled dock. 

:ain (5~ suggestad the possibility of using IlCI'B on peas. Jasmin and Ivall 

(3) observed that liCFE and 2,4-DB showed proru.ee as herbicides when applied 

to Perfection peas under conditions prevailing in 1956 in Ontario and :)lebec. 

Leefe (4) obtained. similar results in IJova Scotia. This paper is concerned. 

i'lith the effects of LiCPDand related compounds applied post-emergent to the 

canning peas. ' 

PRCCIDUREANDllETHODS 

The eX",)eriments were conducted at the Horticultural Organic ::'oi1 

3ubstation, St e , Clothilde de Chat.eauguay , ;uebec, located. approximately 

30 miles south of ;iontreal and at the Horticultural 3ubstation, Smithfield, 

Ontario, located near Trenton, on the north shore of Lake Ontario. 

The soil on which the work was done at Ste. Clothilde is a poorly 

drained :~~argina1 nucl; i'lith 6to 18 inohes of organic soil underlaid by a 

gravelly silt loam. The soil at Smithfield is a moderately vTell-drained 

Berrien sandy loam. 

In 1957 the t;rovlin.1 season was lret and ..~rm at both Smithfield 

and ot.e , Clothilde ,,,hile both locations had e. wet, cold rrol,Ting season in 

1958.

4;', 

•......;SULl'.:l ..NDDISCU.::;JIUU 

,JO reduction in yield of :'erfection \[.-1. :)ei.ls 'laS observed 

Uablts I, II, III) trhen ;~C?B sodium salt \Tas applio

47. 

Sweet late variety suggests that tr.is variety may be more susceptible to 

the to;dc action of this herbicide than any of the others testE4. 

CONCLUSION 

Under the conditions of these tests liCPB appeared to be a safe 

herbicide to use on certain varieties of peas such as Perfection iV.R., 

Cansv~et, Pride, Wisconsin Early ~1eet or Green Giant S.5.39 at ratas of 

16 to 24 oz. ?er acre. This herbicide must be applied ,then the peas are 

L f to 5 inches tall. Dilution of M::PBin 15, 30 C'r 60 gal. of water had no 

effect on the yield of shelled peas harvested. ~1hen ",eed population is 

high the pea crop vrill benefit from the application of tIns herbicide. 

;lesults from M:;PBvlere more consistent than with pre-emergence application 

of DNBP. The margin of safety for peas vlith MCPBis much greater than With 

HCPAand in some cases the '-reed killing properties of V.cPBare better. 

Further studies on selectivity of l1CPBto \-Ieed species and varieties 

of peas under North .unerd.can conditions would be valuable to the 

canning industry. 

1. Carpenter, K. and Ii • .scundy. Investigations into the Practical Value 

of l;CPB as a Selective 1'leedkiller in Leguminous Crops. British 

Heed Control Conference 327-336, 1954. 

2. Fryer, J. D. and R, J. Chancellor. 

HJPB, 2,4-D and 2,4-DB to ~'leeds. 

357-377, 1956. 

The Relative Toxicity of MCPA, 

British l'leed Control Conferenoe 

3. Jasmin, J. J. andL. H. Lyall. Heed (~;1trol in Canning Peas. Proc , 

Northeastern Ueed Cont , ecnr; 34-37, 1957. 

4. Leefe, J. S. The Effect of HCP(B) and 2 J4-D(B) 

Applied Post-emergence 

on Perfection Peas Grown for·Canning. Research Report, National 

Weed Comnittee (Eastern Section) p. 43, 1957. 

5. Wain, R. L. Selective ~leed Control - Some NewDevelopments at 1'1ye. 

Britisll Heed Control Confer~nc~. 311-320, 1954. 

6. 'vain, R. L. Selectivity of Herbicidee. Neeting of VIeed Society of 

America (Abstract) 41, 19.56.

Table I Hate!! of ,rcps (:1a) on Perfeotion rv.R. peas at Ste. Clothilde in 1957 

Yield of shelled Texturemeter -:feed 

Treatments peas per plot readings pop'n. 

lb. sq. ft. 

1. Control, no treatment 18.85 110 98 

2. MCrB 24 oz/A in 15 gal. water 12.85 108 45 

II 

~. 'rCPB 32 oz/A" II " 

14.75 111). 33 

4. MCPB40 oz/A" " " " 17.13 112 51 

5. MCPB48 oz/A II " 

" " 13.20 110 30 

6, MCPB32 oz/A II 30 

II 

" 

14.88 110 50 

7. MCPB32 oz/A " 60 " " 15.38 109 56 

8. MCPA(am) 6 oz/A in 15 gal. water 12.00 106 62 

L. ~.D. at P =0.05 n.s. ",!.SIf :31 

table II Rates of l~CPB (Wa) and 2,4-DB (ester) on Perfection W. R. peas at 

ste. Clothilde in 1958 

Yield of shelled Texturemeter ""'eed 

Treatments in 60 ~1. water peas per plot readings pop'n. 

lb. sq. ft. 

1. MCPA(am) 6 oz/A 10.7 97 38 

2. DNBPIi 1b/A 12.9 89 53 

3. '~CrB 16 oz/A 11.0 92 19 

4. :'~CPB 20 oz/A 8.9 93 13 

5. MCPB24 oz/A 9.9 92 18 

6. 2,4-DB 16 oz/A 11.7 92 16 

7. 2,4-DB 20 oz/A 9.0 90 21 

8. 2,4-DB 240z/A 10.0 95 13 

L.S.D. at P - 0.05 N.S. N.S. 5 

Table III Rates of 'mPB (Na) on "erfeotion ",.R. peas at ~mithfie1d in 1957 

Treatments 

Yield of shelled 

peas per plot 

lb. 

Texturemeter 

readings 

Vieed 

pop'n. 

sq. ft. 

1. CC'ntrol, no weed oontrol 

2. DNBPamine Ii 1b/A 

3. MCPB30 oz/A 

4. HCPB 36 oz/A 

5. MePA (am) 4 oz/A 

6. !~CPA 5 oz/A 

13.8 

15.7 

14.7 

15.0 

15.8 

16.0 

107 

107 

102 

107 

102 

102 

21) 

6 

13 

15 

17 

13

49. 

Table IV Rates of ::CFB (l'la), DNBPand II;CPA(am) on ~'isconsin Early Sweet peas 

at Smithfield in 1958 

Treatments 

Yield of shelled 

peas per plot 

Texturerneter 

readings 

Weed 

pop In. 

1. Control 11.3 93 37 

2. DNBP1~ l~{A 13.2 93 12 

3. HCPA4 cz A 12.3 84 32 

4. HCPB16 oz/A 13.0 . 87 32 

5. lICPB20 oz/A 11.8 89 32 

6. !!CPB24 oz/A 12.0 88 31 

L.S.D. at P : 0.05 N.S. 6 10 

Table V MCPB(Na) applied at the rate of 36 oz of aoid equivalent, per acre 

on different varieties of oanninfl: peas at Ste. Clothilde in 1958 

Yield of shelled peas per plot (lb.) 

Varieties Sprayed Unsprayed 

Perfeotion ". R. 8.4 ~.3 

Alaska Sweet Late 3.2 3.4 

Wisconsin Early ~eet 16.3 12.7 

Pride 11.3 7.6 

Cansweet 12.8 7.9 

~-5-3 9 (Green Giant) 18.4 15.4 

Mean x 11.8 8.6 

% The F value shows a signifioant differenoe (P

50. 

l\n.to;.;r'eOjlanc uecnod has been n:Jj,'oadcast a'l}plica'tion folloV/ed 

i\.irnedic:: .:tel~r b~>, disci11g L:,-C' cleev in two d1r'ections folloHed by 

aeedan., , cr-ops Which have been euc cees ruj l y seeded immedia'tely 

followin~ this uet hod of t r-eat.uen t at rates of 3-G lbs./ac:ce 

include carrots, field and SHeet corn. snap uno dry beans ( except 

Lima bean s ) > ~Jotacoes, flax, alfalfa, trefoil, les)edeza and cLovers • 

Post-ei,leY'3enCe t r-eat-nent e neve ueen made usin~ dil'ected or overall 

U1)lJlica"tions folloHed;",,;! SUitable cuft Lvat.Lon eQuilJli1ent t o 

Lncor'porat e the Evtam into the soil. :li t.n thi s ty)e of a:i>l)lication 

the soil must, be clean cu.lt.Lvaced prio;,' to c'p!Jlicution to destroy 

* Stauffe;,' Chemical Co.. Res , C, Devel. Dept. 

',ri-! - E)CUi,l is st.aur'rer Chemical COIU(Jany's trude-i,lurk rei- eth;,'ldi-n-,jj,'oc:>y!:;hiolcar"uuhlate.

,51. 

estc::.~JIJ.silac~ ueeds , Ci'Oi-'S ,rhiC,1 nave ueen succe'.;"ftlll;; cr-ea ceo Hl 

this i;1c, nne; at rates of :)-'" los ,jUCl' e incluc 1,e field c.:.oc1sweet corn, 

utl'a\uel';.'ies, tomatoes, and .ot.at oe a. 

30il Inuoio.Jol"a(;ion j{esul\;B on YeJ.lol'l ;JutSiD.SfJ O,:r;;uinec1 Durin:.; Glle 

1))0 3eaSO,1: 

Interval 

C.'O,)';}, 

~.: 

.Jhen LiJs.j Af',Jlicadon to 

1.,J)lied ~ Observation t, 

tJ Contlool 

Dean3, S,1a~J l' rei)1 arrt 3 3 ii10S. 95 

~. 

Beans, snap Pre)1ant ;: 

.J 

moe. 90 

("lr\ 

Deans, snap PreiJlan;; 3 mos. .,iU 

Corn, field Prel)lan~ j 1'~' mos. S'7 

corn , field ppe1Jl an t ~) 

3 mos• . 90 

ccrn , field l:':ce;Jla,1i; :J l~' i:108. 100 

corn , suee c b.'eplant d. 1 mo, 100 

st rauoez-r-Le s l'ost-e«(ler:..,. 1 1:10. 90 

S'Gra\11JGi. 'l'ies Pos'c -er.ler ..... 

t:! mos. 

'" 

9:; 

Strawbelloies Fost -euer'g , ~ 2 mos. 93 

None ~ l'~ uo s , 90 

Hone (. 2 mos. 100 

''Jone ~ 

3 1110S. 100 

'It No L1,jU:':'YHas obca inee on un;)' of the CPO\Js. 

SUl.1ma:c;y': 

~~)t;aljl is effective in conti'ollil{, hut~1'a.ss and es.;uLlished quack 

:5lass :j.,~ ..adell,tio{\, .t o. ..lUtl(,' annual :"l'assy and J.ll'o.CtcUeave,c/weeds. 

Fo!' effective cont.r-of unde r a wide variety of conditions, the Ep'ca.'l 

(,lUSC',e '';hOl'ou~hly Lncor-por-at.ed into the soil. dc;.tes of 3 and i.l 

1 btl .jucl'e fOi' theconCl'ol of nut jr-a sa and quack::;l'ass respec'ci vel".. 

nave >~oo,!en to 0e adequate in ;Jes'Cel"n United States unen t hor-ough 

soil incol°»o~':.:.tion is used. Inclica'~ions are tilc;.'C che ae :L'ates will 

also t):L'ovo'co oe effeci;ive 1,1 &stel'n Uni~ed states uhen ti10r'OU0; ):;:J.

52. 

INFLUENCEOF SOIL MOISTUREONT.HEACTIVITYOF EPTC, CDEC,ANDCIPCl 

J. R. Havis, R. L. Ticknor. P. F. Bobula 

University of.Massachusetts, Waltham. 

Results of 1957 field trials in the northeast with the new 

carbamate herbicide EPTCwere extremely variable. A fairly typical 

report came from Long Island (2) where EPTCwas tested on onions, 

corn. and tomatoes with unsatisfactory weed control. It was noted 

that herbicide treatments were applied to moist soil. On the other 

hand, the same chemical gave good weed control in NewJersey (S) 

where the application was. made to moderately dry soil. Other 

reports. of which many were unsatisfactory, did not mention soil 

moisture conditions. Tests conducted in California (1) showed 

that EPTCgave "excellent" weed control when applied to dry 

soils and irrigated 7 days later, but poor results when applied 

to wet soils. 

Field trials were conducted at Waltham to evaluate the 

influence of soil moisture on EPTCin the northeast. Two other 

carbamates, CDECand CIPC. were also included to observe whether 

or not they were similarly affected. Since EPTChad been reported 

to par form well when incorporated into soil (7). this factor was 

also included. 

GENERAL-PROCEDURE 

The experiments were conducted on Gloucester fine sandy loam. 

Emulsifiable liquid formulations of EPTC, CDEC.and CIPC were applied 

at the rate of 8 pounds active ingrediant in about SO gallons of 

water per acre. Each chemical was duplicated on areas where soil 

moisture was controlled to produce dry or wet conditions. before or 

after application. 

Immediately after being treated, one-half of each plot was 

cultivated about two inches deep using a scratcher attachment with 

staggered teeth. This tool appeared to mix dry soil fairly well. 

The mixing was probably less thorough in wet soil. 

Applications were made to weed-free soil. The principal weeds 

that appeared later were species of Portulaca. Amaranthus, Chenopodium, 

and Lamium. 

lContribution Number 1179. Massachusetts Agricultural Experiment 

Station.

53· 

MOISTUREATTIMEOF APPLICATION 

This experiment w~s'de~ig~~a to measure the effect of application 

of the ch$micals to. dry and ~et soiis. The area chosen had 

recently been &etto a groupof lIIisc81laneou8 small.nursery plants 

at 4' x 4' spacing. Plots were 400 square feet. The so11 surface 

was dry, but sub-surface moisture was alllplefor plant growth. The 

blocks indicated as ''wet'~ were irrigatedwitA about 11/2 inches 

df water the day before t~ 'treatments wer's 'ap'plied ~m June S. The 

so11 was about as. wet,aseould' be ,cutH\,at~dwi,th~ut p1:Jddling. 

• " • 1 ~. : I ' • "', " - . • 

Weed control was rated 22 days and 32 days after application 

of 'the herbicide. These ratings are given in Table 1 and 2. . 

Table 1. Average Rating of WeedGrowth1l days After 

Application of Herbicides to Wet and Dry Soils. 

(I-clean;' 3-"sa.tisfactory"; 9-rtocontrol) 

'. 

' .. 

SOILWET 

SOIL DRY 

'. 

Cultivated Not Cultivated cultivated Not Cultivated 

" 

'i 

EPTC 8.5* 9* 

i 

/' 

'4 '. 

CI1£C' 2 2 I 1.5 

CIPC 3.5 3 5 4 

Check 9* 9* 9* 9* 

*Indicates plots that were hand weeded after this ratingf' 

Table 2. 'Average Rating of WeedGrowth 32 days After 

Application of Herbicides to Wet and Dry Soils. 

(I-clean; 3-"satisfactory"; 9-nocontrol)' 

, SOILWET SOIL DRY 

< , ' .." 

Cult:l:vated Not,~cuitivated ' C,,!ltivate~ Not Cultivated 

EPTC C C 3 6.5* 

CDEC , 6.5* 4· ' 1 3 

.. p , ;'A. 

, ;" 

CIPC 7* 3.5 7.5* 4 

,,*Indicates {'Jot,s that were hand weeded after this rating~ 

., iC Had been 9leaned by hand 10 days prior to this rating~ 

, , ,

54. 

EPTC applied to wet soil failed to control weeds. Furthermore, 

the attempt to incorporate the chemical into wet soil 'by 

cultivation did not improve the results. This chemical gave ,better 

weed control when applied to dry sOil, and further improvement 

resulted from incorporation. ' 

CDECwas more effective on dry soil than on wet soil, but the 

difference was not as great as with EPTC. Cultivation reduced the 

effectiveness on wet soil but enhanced weed control in dry soil. 

Of the combinations of materials and conditions in this experiment, 

CDECincorporated into dry soil was rated the best treatment. 

CIPC was not influenced by the soil moisture variant. 

Cultivation reduced the effectiveness of this herbicide about 

equally in both wet and dry soils. 

No significant crop damage could ,be ~,sociat~d with the 

treatments. 

MOISTUREFOLLOWINGAPPLICATION 

This experiment was designed to evaluate the influence of 

irrigation, or precipitation. after application of the three 

carbamates to dry soil. Plots were 200 square feet. No crop was 

involved in this test There had been no rain for 6 days. The 

day before application on July 2. the entire area was disked 

thoroughly and smoothed. This resulted in a 2 to 3 inch layer 

of powder-dry soil on the surface. Immediately after the application 

of the herbicides. about 1 inch of irrigation was given the 

blocks designated to receive this treatment. The non-irrigated 

blocks remained dry for 8 days. 

Weed control ratings 5 weeks after treataent are given in 

Table 3. 

" . 

~able 3. Rating of Weed Growth Showing Effect of lInch 

Irrigation,Immediately Following Application of 

Three Carbamate. at 8 lbs./A on Dry Soil. Ratings 

Taken 5 Weeks Alter Treatment. 

(l-Clean; 3-"Satisfactory"; 9-No Control). 

IRRIGATED 

NOTIRRIGATED 

,Cultivated Not Cultivated Cultivated Not Cultivated 

EPTC 2.5 1 2 3 

CDEC 2 1- 2.' 3.S 

CIPC 6.5 4.5 3•.5 4.5

55. 

EPTCand CDECwere strikingly similar in performance 

in this experiment. Weed control was rated from excellent to 

satisfactory under all conditions. Whennot cultivated, weed 

control in the irrigated plots was superior to the not irrigated. 

Similar results with CDECwere reported by Rahn (6). Irrigation 

had no effect when these chemicals had been incorporated with the 

soil. 

CIPC did not respond the same as the other two 

carbamates. When not cultivated, the results were equal whether 

irrigated or not irrigated. Cultivation reduced the effectiveness 

of this chemical when followed by irrigation, but did not 

when the soil remained dry. 

pISCUSSION 

From a practical standpoint, the results of these tests 

indicate that: (a) EPTCis an effective pre-emergence herbicide when 

applied to dry soil, and its performance can be enhanced by irrigation 

immediately after application. Failure can be expected when applicatiqn 

is made to wet soil. (b) CDECis affected by soil moisture in 

the same way as EPTC, although the degree of effect is not as great, 

especially with regard to moisture at the time of application. These 

results agree with the observation on eDECreported by Danielson (4). 

(c) CIPC is affected little, or not at all by reasonable soil moisture 

variation. Temperature has been considered to be the most important 

factor affecting this chemical, as reported by Danielson (3). 

(d) Both EPTCand CDECare promising herbicides for 80il incorporation 

to a depth of 2 inches. 

EPIC has been incorporated into soil in additional trials 

by disking and with rotary tiller and at various rates of liqUid and 

granular formulations. Weed control has been consistently better on 

dry than on moist or wet soils. 

The "wet" soil in these experiments might be considered 

an extreme condition, i.e. wetter soil than would normally be treated 

with.a pre-emergence herbicide. FUJ:'ther testing is needed to find 

how moist a given soil can be at the time of application without 

reducing the effective weed control of EPIC and CDEC. 

SUMMARY 

EPIC, CDEC,and CIPC were compared at 8 pounds per 

acre under conditions of (a) dry and wet soils at time of application, 

and (b) irrigated 

application to dry soil. 

and not irrigated immediately after 

The factor of cultivation immediately 

after application was included under the various conditions of 

soil moisture.

56. 

EPTCfailed to control weeds when applied to wet soil. 

Weed control was enhanced on dry soil by e,ither cultivation 

or irrigation after application. 

CDECwas more effective when applied to dry soil than 

on wet soil. Weed control was i~roved when incorporated into 

2 inches of dry soil or when followed by irrigation. 

CIPC was unlike EPTCand CDSCin that the variations in 

soil moisture had little or no influence on its effectiveness, 

and incorporation generally reduced weed control. 

LITERATURECITED 

1. Antognini, J. Activity of EPTCas effected by soil moisture 

at time of application. Proc. N.E.w.e.C. 398. 1958. 

2. Da111O, S. L., R. C. catee, R. L. Sawyer, R. W. Robinson, 

andH. H. Bryan. Progress report on weed control in onion, 

corn, tomatoes, and seed beds~ Proc. N.E.W.e.c. 74-80. 1958. 

3. Dr.atel.oa, L.L.and Vill.'ginlaA. France. Experimental and 

field use of 3-chloro 1 P C' on vegetable crops in tidewater 

Virginia. Proc. N.E.W.C.e. 73-79. 1953.' 

4. Danielson, L.L. Evaluation of pre-emergence spray and granular 

applications of CDle on vegetable leaf and cole crops. Proc~ 

N.E.W.C.C. 17-22, 1957,' 

5. Meggitt, W. F. Progress report on herbicides for weed control 

in tomatoes. Proc. N.E.W.e.e. 92-95. 1958. 

6. Rahn, E~ M. A comparison of several herbicides for lima bean 

weed control, under high and law soil moisture levels. 

Proc , N.B.W.e.C. 137-142. 1956. ' 

7, Stauffer Che~ical Company, Agricultural Research Laboratory. 

EPTAM- ..1957 Field Results (mimeo) dated February 14,1958. 

Acknowledgment is made'to Stauffer Chemical Company'for financial 

assistance; and to Monsanto Chemical Company, Niagara Chemical Company, 

and Stauffer Chemical Companyfor supplying the chemicals used.

1 

57. 

COMPARISONOF FIVE HEmlICIDES USED TO KILL ESTABLISHED 

POJ::lONIV'! IN A MATUREAPPU: ORCPJUal 

Oscar E. Schubert 1 

Five herbicides were applied to well established poison ivy 

in an old block of apple trees growing on a steep hillside. The 

sod in this orchard had not been disturbed for at least twenty 

years. The grass is mowed about twice each year. Since neither 

cultivation nor herbicides had been used to check the growth of 

poison .ivy, many plots beneath trees had as much as 53 to 70 percent 

of the ground surface cove=ed with poison ivy. Many tree 

trunks were completely covered with poison ivy which sometimes 

reached the top of the trees. No plots were selected for treatments 

or checks unless at least one-fifth of the surface had 

poison ivy plants. 

The principal purpose of this study was to evaluate the 

ability of the herbicide to maintain the area free of poison ivy 

for at least one year after treatment. Only herbicides having 

known ability to kill poison ivy were used. 

The herbicides used were ATA, Ammate, 2,4,5-T Ester, 2,4,5-TP 

and 2,4,5-T Amine. The ATAwas made up by using 4 pounds of a 50% 

formulation per 100 gallons. Am:nate sprays were made with 75 

pounds of Ammateper 100 gallons. 2,4,5-T Ester, 2,4,5-TP, and 

2,4,5-T Amine sprays made at tlterate of 2 quarts per 100 gallons 

for each of the herbicides, respectively. Preliminary trials 

indicated that an application rate of 200 gallons per acre was 

necessary to cover the dense growth of grasses and weeds. The 

applications were made at as. nearly the seme rate as possible 

over the entire plot (by-timing the sprayi.ng operation) regardless 

of the density or even presence of poison ivy in the area 

being eprayed. The major obstacle to this procedure was encountered 

in plots with poison ivy running up the trunks. In these plots 

only the lower four feet were sprayed. This did not result in an 

appreciable reduction of spray available for the remainder of the 

plot and at the same time no effort was made to spray the poison 

ivy further up the trunk than four feet. This did not appear to 

be inconsistent with the other procedure since many of the weeds 

were tr-ree to four feet in height at the time of spraying. 

The application equipment consisted of a 50-gallon power 

sprayer with a three-noz~le boom delivering the spray in a flat, 

fan pattern. The pressure was maintained at 15 to 80 pouods

whil~ spraying. The plots were classified accorJing to their 

relative density of poison ivy, and then were grouped into twelve 

replications, each with similar poison ivy stands. Six replications 

consisting of six plots each were laid out around trees, 

and another six replications were laid out in spaces between the 

tree plots. These plots in the spaces were in tree rows and not 

between tree rows where orchard equipment normally travelled. 

The sprays were applied between August 13 and 17, 1957. 

The treatments were made at random within each replication. The 

plots were given numbers to simplify later observations and stand 

counts, and to avoid bias. 

Each plot was carefully inspected in October of 1957. No 

living poison ivy plants were observed in any of the sprayed 

plots. This was, of course, only the secondary purpose of the 

study since the extent of regrowth after a year was of greater 

concern. 

In September, 1958, the density of poison ivy was recorded 

for each plot as the number of leafy stems that were visible. An 

estimation of the stand on the" basis of percentage of ground surface 

covered did not seem feasible, except for check plots, because 

the areas covered in some cases was less than one percent 

of the surface and seldom was over 5 to 10 percent. Thus a count 

of 11 stems may indicate only a poison ivy plant or two, and extending 

over a relatively small amount of the plot surface. 

In Table 1, the number of poison ivy stems is tabulated for 

each replication and traatment. All treatments differ significantly 

from the control or check plot, but do not differ significantly 

from each other.

· 59. 

Table 1. Number of poison ivy stems in l/lOOth-acre plots one year following 

herbicide applications to established poison ivy in an apple 

orchard a 

Original 

Poison 

R

60. 

The ~Iode and Rate of Release of CIPC 

from Several Granular Carr ier s 

1/ 

L. L. Danielson- 

2/ 

AbBtract- 

Basic infor:nation on the mode and rate of release af herbicides from 

granular carriers is critically needed if we ar e to understand the reasons 

for the variable results obtained in field experiments. Experiments 

di.r ected toward this goal were initiated with a study of the activity af 

CIPC [isopropyl N-(J-chlorophenyl)carbamate] formulated on granulated 

uncalcined attapulgite, calcined attapulgite, vermiculite, pyrophyllite, 

perlite, and activated charcoal. 

A bioassay for CIPC based on the rate of elongation of the hypocotyls 

of germinating cucumber seeds in petri dishes was used to determine the 

activity of the chemical. The bioassay was used to measure the response of 

cucuno er seedlings to vapor and contact activity of crystalline CIPC and 

CIPC formulat ed on the granular carri EI:'s , The pronounced contact and vapor 

activities of CIPe crystals were used as the standards for comparison. 

CIPC at the rate of 0.5, 5, 50, 500, or 5000 gammas to each 100-mm x 15-mm 

petri dish were used to establish a constant chemical-to-air-volume relation 

for the assay. These amounts of the cheml.cal were introduced on 1 gm of 

each of the granular carriers stOOl.ed. An aluml.num fol.l container was 

placed in each petrI. dish to hold the test herbicide in the vapor studies. 

Contact activity of CIPC from all the granular carriers, except 

activated charcoal, ltlich did not produce growth responses at any of the 

formulation levels used, was approximately the same. 

Vapor activl.ty of CIPC from the formulated granular carriers leS related 

to their physical structure and adsorptl.ve caplcity. Vapor action 

of treated attapulgite granules was enhanced by changl.ng their physical 

structure by moistening with water. Carr l.ers ltll.ch did not change 

physical structure on cootact with water remained urohanged in intensity 

of vapor activl.ty. 

Y Plant Physiologist, Creps Research Division, Agricultural Research 

Service, U. S. Departma1t of Agriculture, Beltsville, Marylaro. 

y Paper to be offered for p.1blication in the Journal at the Weed Soc iety 

of America.

61. 

nelatively impervious carriers of low adsorptive capacity such as 

PJ'rophyllite and vermiculite were highly contact- and vapor-act ive. Hildly 

adsorptive clays such as the attapulgites were intermediat e in vapor and 

contact, act i vi ties. The highly adsorptive activated charcoal granules hel d 

the GIPG tenaciously and neither vapor nor contact activity was ebserved 

at the standard levels ofccncentration used in these experiments. 

Use of the metho:ls describ ed in further s.1lldies includi,IJg t he effect 

of tanperature, light, and methods of formulatiQ'l on the level and . 

duration of activity of GIPC and other carbamates from granular carriers 

is visualized.

6? 

EFFECTOF RECOMMENDED ANDEXCESSIVERATESOF CERTAIN 

HERBICIDESTOAPPLETREESOF VARYINGAGES 

Oscar E. Schubert 1 

Herbicides may sometimes be applied primarily to kill 

a particular weed without knowing what the relative safety of 

the herbic~de may be when used over a period of several years 

or if excessive rates can be applied with safety. A study was 

initiated in 1957 at the West Virginia Horticulture Farm near 

Morgantown to obtain additional information concerning the tolerance 

of apple trees of varying ages to certain herbicides, and 

to determine what the effects of annual herbicide applications 

might be on these trees. Some of the herbicides were included 

since they were or could be recommended for control of weeds or 

grasses and others were tried for possible beneficial effects 

upon tree !r."owth. 

In 1957 and 1958, ATA, Ammate, 2,4,5-T Ester, 2,4,5-T 

Amine, 2,4,5-TP, DNBPAmine, DNBPAmine + Da1apon, and DNBP+ 

Oil + Water were applied during July. These herbicides were 

mixed at the recommended concentrations and sprayed at the rate 

of 200 gallona per acre for the basic rate (X) and also at the 

rate of 1000 gallons per acre to obtain the five fold application 

(5X). It was thought that an orchardist or his workers 

would be more likely to overspray, by trying to cover the area 

thoroughly or by a calibration error, than he would to add five 

times as much of the herbicide to the spray tank. 

The sprays were mixed with the following amounts of herbicides 

per 100 gallons of spray: 

ATA--4 pounds of 5at W.P. 

Ammate--75 pounds. 

2,4,5-T Ester--2 quarts. 

2,4,5-T Amine--2 quarts. 

2,4,5-TP--2 quarts. 

DNBPAmine--10 quarts to water previously softened 

with Ca1gon. 

DNBPAmine + Da1apon--10 quarts Premerge + 5 pounds 

Dowpon (85~ Da1apon) to water previously 

softened with Ca1gon. 

DNBP+ Oil + Water--3 pints DowGeneral + 20 gallons 

No. 2 fuel oil + 80 gallons water. 

1 Associate Horticulturist, West Virginia Agricultural 

Experiment Station.

63. 

Tre~s were selected in three different age groups with 

two replications in each to study the possible variation in 

response due to age of tree. The circumferences of many trees 

in each potential replication were measured at a height of 15 

inches from the ground and marked with paint for future measurements. 

Then replications were made up from trees having 

the smallest range in circumference. The six replications were: 

two of Double Red Delicious replants set out the previous winter 

(December 1956); one replication 

another of young Golden Delicious 

of young Red Rometrees and 

trees just starting to bear 

(set 1948); and two replications of mature Red Stayman trees 

(set 1937). 

An area of 1/200th-acre was sprayed around the young replants 

and l/lOOth-acre plots were sprayed around the young and 

mature trees. 

A 50-gallon sprayer with a 3-nozzle boom delivering a flat 

fan spray pattern was used. The operating pressure was maintained 

at 75 to 80 pounds and a stop watch was used to apply the 

proper quantity of spray by timing the spraying of each tree. 

Calibrations were made before and occasionally between herbicides 

to be certain of the amount of spray delivered by the boom. 

In July, 1958, small white-green to yellow-green chlorotic 

spots were observed on the young replant Red Delicious at both 

X and 5X concentrations of Ammate. Similar spots were found on 

the 5X Ammate treatment on young Golden Delicious and one of the 

two mature Red Stayman trees. By September, 1958, the other 

mature Red Stayman tree also showed the distinctive spots but 

no spots could be found on either of the Red Rome (X and 5X) 

trees or the two Red Stayman trees having had the X application 

rate. A more detailed description of the early symptoms'of an 

excess of Ammateare: At 60K magnification these areas are 

roundish to elliptical in shape (not angular). The chlorotic 

areas may appear anywhere in small islets between veins, or 

even on veins, but do not fill the islet with chlorotic tissue. 

No evidence of necrosis was observed in these areas. Where the 

spots are more numerous they seem to merge but do not evenly 

cover one or more islets. Occasional spots may be found scattered 

anywhere on the leaf blade. 

The previously described injury from Ammatehas been the 

only visual foliar symptom of herbicidal injury observed in any 

of the treatments over a period of two seasons except where 

foliage was contacted directly by spray. This experiment will 

be continued by annual herbicide applications, periodic observations 

and trunk circumference measurements.

GRANULAR l\NDSPRAYAPPLICaTIONSOF CERTAINHERBICIDES 

J;I 

IN STRAWBERRIES l\ND~\SPBERRIES 

~I 

W. E. Chappell and Fred L. Bower. Jr.· 

Virginia Agricultural Experiment Stat10n 

Blacksburg. Virginia 

The work reported herein ~ncludes two experiments on weed control in 

strawberries and two experiments in raspberries. The various chemicals used 

and the type of treatmentl included in each experiment are presented and discussed 

separately. 

STRAWBERRIES 

Experiment I - Spray va. granular treatments of sesone and neburon 

Strawberry plants of the Blak~re variety were planted in four-foot rowl 

on April 15. 1953. Individual plots of 8 x 20 feet were staked out and treated 

on May 17. immediately following cultivation and hoeing. Four replicates 

were used. Weed control and plant vigor ratings were made on June 4 and again 

on June 24. On June 28 a second application of the herbicide was made. Weed 

control and plant vigor ratings were again made on July 11 and on August 27. 

The chemicals were applied al a water spray in a volume of 40 gallonl per 

acre and on No. 4 vermiculite at a rata of 60 pounds per acre. The chemicals 

used. along with weed control and vigor ratings of the plants are given in 

tables 1 and 2. 

Table 1 - Weed Control Ratings. Granular vs. Spray 

- - - - - - - - - - Rate-in Ibs.- -:::::: : :: :R:!tIni~::::::::::=-_ 

_ _C!!~i.s.a,! p!r_a.s.r.! J.J!n!.2 __ lu~e_2.2 __ lu'!y_ll __ AUj,._21 _ 

1/ 

Sesone (S) 3 7.75 a- 6.15 bc 7.25 c 5.5 dc 

Sesone (G) 3 6~88 b 6.00 e ' 7.00 cd 6.00 e 

Neburon (5) 6 ~.13 a 8.00 a ~.75 a 7.75 a 

Neburon (G) 6 7.88 a 7.5 ab 8.25 b 7.50 b 

Check 5.63 c 3.25 d 6.25 d 3.00 c 

* 1 - No control. 10 - 100;' control 

,!/ Figures followed by same letter are not significantly different. 

--0--------------------------------------- 

- These studies were lupported in part by a grant from the ZonoliteCompany. 

2/ .. . 

- Plant Physiologist and Graduate Relearch Assistant

65, 

Table 2 • Plant 

Vigor Ratings. 

Sesone (S) 3 10.0 a 9.5 a 8.0 a 

Sesone (G) 3 8.5 a 8.5 a 7.5 a 

Neburon (S) 6 4.5 b 3.0 b 2.5 b 

Neburon (G) 6 8.0 a 7.5 a 6.0 a 

Check 9.0 a 8.5 a 7.0 a 

* 1 • Plants dead, 10 • Vigorous plants 

1/ Figures in a column followed by the same letter are not significantly 

- different. Comparison should be made within columns and not between 

columns. 

As shown in the data, neburon at G pounds per acre, was more effective in 

controlling the weeds than was the sesone. ~lith both chemicals the spray 

application gave slightly better weed control than did the granular application. 

Plant vigor was seriously lowered ~n the case of the neburon spray as compared 

to the sesone and check plots. This was not true of the plots receiving 

granular neburon. 

In this experiment granular neburon l~as the most satisfactory treatment. 

Experiment 11 • Screening Test. This experiment was handled .the same 

as experiment 1 except that four varieites of strawberries were used and only 

two replications were made. The varieties Blakemore, Pocahontas, Fairfax 

and Empire were used. The chemical treatments were applied on May 17 and 

again on June 28. Weed control and plant vigor ratings are presented in 

tables 3 and 4. . . 

Table 3 - Screening - Heed Control 

EPTC (G) 5 8 b 8 

EP'fC (S) 2/ 5 8 b 7 

Ox-tho (G) - 25 8 b 6 

Ortho .(G) 50 7 b 7 

cr:.:c. (G) 3 8 b 6 

CIPC (S) 3 8 b 7 

Sesone J. CIPC (5) 2 ~ 1 8 b 8 

Hmazine(S) 1-1/2 8 b 5 

CHECK 10 a 8 

NS 

* 1 • Plants dead, 10 - N.S. vigorous plants 

1/ Figuresin a column followed by the same letter are not significantly 

- different. 

?J ~~ ~Ae~"G a"~ ~~ ~hl~pn T~~

66. 

Table 4 - Screening plant vigor 

EPTC (G) 5 8.00 7.0 ab 7.0 6.5 b 

EPTC (5) 5 7..25 5.5 bc 6.5 5.5 b 

Ortho (G) 25 7.5 7.0 ab 7.5 6.0 b 

Ortho (G) 50 8.00 8.0 a 7.5 6.5 b 

CIPC (G) 3 7.75 7.0 ab 6.5 5.5 b 

CIPC (5) 3 6.25 5.0 c 7.0 6.0 b 

Sesone

Table 5 • Weed and Vigor Ratings • Red Raspberries 

--- -- - - - _. Rate-in pounds- -_-_-_-_-'!le!d!-i./_-_-_-_-_-_-_-_vJ:.gE.r.-li...·-_-_-· __ 

fh.!:1l1J:.cj!1 E,e,Ej!c,Ee lu,!!e_4 lu.!!e_2~ O£tE.by_ ll __ 

Jinitro 

IJinitro 

EPTC 

EPTC 

Neburon 

5imazin 

Check 

(G) 

(G) 

(G) 

(G) 

(G) 

(G) 

7.5 

9.0 

7.5 

10.0 

6.0 

2.0 

3/ 

6.75 d 

7.3:; bed 

7.75 abc 

7.25 cd 

8.5 a 

8.25 ab 

5.25 c 

1/ 1 • No control, 10 - 1:)0%control 

1/ 1 - Plants dead, 10 • Vigorous plants 

6.50 bc 

1.75 be 

7.00 ab 

7.00 ab 

7.75 ab 

8.00 a 

5.50 c 

9.5 

8.5 

7.5 

8.5 

8.0 

8.5 

8.5 

N5 

3/ Figures in a column followed by the same letter are not significantly 

- different. 

Hone of the treatments resulted in reduced vigor of the raspbert'ies. There 

was moderate foliage burn in the neburon and dinitro plots but resulted in 

no permanent damages. Simazine and neburon and EPTCrosulted in satisfactory 

weed control for about six weeks. 

Experiment 2 • Blac~~ Raspberries 

The same general procedure was used in this experiment as in the previous 

one. The only difference being that both granular and spray applications 

were used. The applications were directed at the base of the raspberry 

canes. Peed control ratings sere made at three and six weal,s after treatment. 

The data are presented in table 6. 

Table 6 - Peed Control· Black Raspberries 

_. 

Chem;l.cal. _ 

Dinitro (G) 

Dinitro (5) 

5ihazin (5) 

Eihazin (G) 

Neburon (5) 

Neburon (G) 

EPTC (5) 

EPTC (G) 

Check 

Rates in pounds 

per acre. 

12 

33 cc/l.3 qt. oil, 

13 gal H201 lOa ~c;. ft. 

3 

3 

5 

5 

6 

6 

• - 

• : JU'll8_4. 

11 

7.38 

8.00 

7.75 

8.38 

6.38 

8,.00 

6.63 

6.75 

5.16 

• Weed.*· 

_ 

6.75 abc 

6.50 bc 

6.75 abc 

8.~ a 

5.25 cel 

7. 75 ab 

5.50 c 

5,25 cd 

3.30 d 

* 1 - No control, 10 - 100%control 

1/ Figures in a column followed by the same letter are not significantly

6El. 

There was no apparent damage to the raspberries from any of the treatments. 

This was probably due to the use of direc Led applications. .,11 of 

the chemicals except EPTCresulted in satisfactory weed control for three 

weeks. After 6 weeks only the s1mazine and neburon spray treatments were 

holding the weeds satisfactorily. 

Etrawberries 

Raspberries 

SU1lIIIlary 

1. Cne application of neburon on vermiculite at 6 pounds per acre 

resulted in good weed control for six weeks without causing injury 

to the plants. The same chemical as a spray was much more injurious. 

2. Sesone resulted in no injury but the weed control was poor after 

three weeks. 

1. fimazine and Neburon resulted in the most satisfactory weed control 

and resulted in no injury to the raspberries.

HERBICIDETRIALSIN A MATUREVINEYARD 

Oscar E. Schubert l 

It is often difficult, in practice, to make the necessary 

repeat applications suggested with several of the herbicides 

used to control or retard weed and grass growth beneath a grape 

trellis. With this problem in mind, single applications of 

several herbicides and combinations of herbicides were made. 

The herbicides 

used were: 

1. DNBP+ Oil + Water (2.5 pints DowGeneral + 20 

gallons kerosene + 80 gallons water) 

2. DNBP+ Oil + Da Lapon (same concentration of DNBP, 

Oil, and water plus enough dalapon to give a 3 

pounds per acre rate) 

3. DNBP+ Oil + ATA(same concentration DNBP, oil, and 

water plus enough ATAto give a 4,pounds per acre 

rate) 

4. Dalapon (3 pounds/acre) 

5. Dalapon (3 pounds/acre) + ATA(4 pounds/acre) 

6. ATAat 4 pounds/acre 

7. ATAat 8 pounds/acre 

8. Check 

The sprays were applied with a 50-gallon Myers power sprayer 

using a three-nozzle boom. Each nozzle delivered a flat fan-type 

spray pattern. The boom was curved down 90 0 at the end so the 

main part of the boom was held horizontal to the ground while the 

nozzles were perpendicular to the ground. 

A working pressure of 70 pounds was used to reduce atomization 

and spray drift,. A strip about 2 feet wide was sprayed 

along each side of the trellis of the mature Concord grape planting. 

All new canes', were tied up to the two-wire trellis during 

the two weeks preceding the spray application so as to eliminate 

direct spraying of the grape foliage. The lower portion of the 

grape trunk was sprayed the same as the surrounding weeds. 

'\ 

The ATAsprays, ae4 and 8 pounds per acre were applied on 

June 15, 1958, and the ,other sprays were applied June 23, 1958. 

The app lication rate was 200 gallons per acre. At this time many 

weeds and grasses had made a substantial amount of growth. The 

treatments in each of the two replications were selected at random 

with five grape plants "in each plot. The check plots were mowed 

with a sickle about the time herbicides were applied. 

1 

AAAo~inte Horticulturist. West Virginia Aaricultural

70. 

At the time the applications were made it seemed that an earlier 

date may have been desirable, but had the sprays been made 

earlier it is likely that a repeat application would have been 

necessary for more of the herbicides. By spraying at this time 

many late-starting weeds were killed or severely injured as well 

as those weeds which start growth very early in the spring. Most 

of these weeds and grasses, if not killed, did not have enough 

time ,to recover and present a problem by grape harvest time. 

A summary of observations from the different treatments i. 

given in Table 1. AtA at the rate of 8 pounds of active material 

per acre gave the best degree of weed control. ATAat 4 pounds per 

acre and a combination of dalapon and ATAgave what was considered 

an entirely acceptable job of weed and grass suppression. DNBP+ 

011 + ATAwas not. as effective, perhaps due to rapid k11l of plant 

parts from the DNBPand oil, thus decreasing the amount of ATA 

absorbed. DNBP+ oil + dalapon, DNBP+ 011, and dalapon alone 

would have to be repeated to achieve a satisfactory degree of weed 

and grass suppression. General recOlIlllendation fer the use of 

dinitros and dalapon have indicated the need for repeat sprays. 

Table 1. Percent of living cover and extent of weed and grass 

recovery in various grape herbicide plots. 

% Living Have weeds Have grasses 

Herbicide a cover b recovered?c recovered? 

ATA8 pounds/acre 15 No. Weeds killed or Very slightly 

stunted 

AtA 4 pounds/acre 25 Very slightly Slightly 

Dalapon + AtA 30 Slightly--2-3" Slightly 

additional growth 

DNBP+ 011 + AtA 45 ~derately Moderately 

DNBP+ 011 + Dalapon 75 Yes. Moderate Moderately 

DNBP+011 80 

reduction in 

weed growth 

Yes. Moderate Moderatl.lly 

reduction in 

weed growth 

Dalapon 85 Yes. Slight Moderately 

reduction in 

weed growth 

Check 100 Yes. Many 3 to Yell. 8-15" 

4' tall tall 

3 ATAslone s~rays a~plied June 15, all others applied 

June 23, 1958 

b Check" 100% and complete control of vegetation" 07,. 

c With the more effective IIprays the weeds have made little 

or no growth after spraying. All observations were made 

September 4, 1958

71. 

\'leed Control in Sweet Corn in 1958 

E. M. Rahn 

University of Delaware 

DNBPamine (amine salt of 4,6 dinitro-o-secondar,y butyl phenol), 

applied to sweet and field corn while in the "spike" stage, is a widely 

acce~ted practice .for control of·both annual grasses and broadleaf weeds. 

It was felt that 3-amino-l,2,4-triazole applied similarly at low rates 

might do equally well possibly at less cost. Therefore this preliminary experiment 

was run in 1958. 

P.rocedure 

Seed of the NK-199variety was planted May 23, 1958 in a Norfolk loalllY 

sand at the Georgetown Substation. The treatments used (Table 1) were replicated 

four times in randomillle'dblocks. Plots c,onsisted of three rows 25 . 

fee1; .long . Chemicals were appUed in water sprays at a 50 gal./A. rate. 

Emid (a wettable powder containing 75 pe~ cent 2,4-dichloropheno~ acetamide) 

was applied immediately after planting. Three days later 0.95 inches of 

rain fell. DNBPaJlI1ne (applied as Premerge) and am!1iotriazole'(a:pplied as 

Weedazol, 5~ active) were applied on June 2, ten days after seeding. On 

this date the corn was about two inqhes tall and was actually beyond the intended 

"spike" stage, for the first .t'iJO or three 1ea:ves had unfolded. 'The 

hoed check plots were hoed and cUltivated as needed throughout the season. 

All other plots were never hoed, 1:iu'tafter taking weed counts 'on' June- 11, 

they too received tractor cultivatj,on as needed. Also on this date, since a 

heavy seeding rate was used, the plant stand on all plots was reduced to one 

plant per foot of row. . . 

Crabgrass was the predominant weed. There was a light infestation of 

lamb's quarters, pigweed, and ragweed. On June 2, when the DNBPamine and 

amino triazole were applied, -ma1'!Tweeds had emerged .and were about a hail 

inch high. Yields were taken on the center rows of each plot only. 

Results 

~ 

and Discussion 

All three herbicides used gave good conunercial weed control (Table 1). 

On June 11, the date weed counts were made and nine days after amino triazole 

was applied, it was noted that some of the crabgrass was just stunted 

by amino triazole. Most of this, however, was subsequently killed by tractor 

cultivation. 

Plant stand was not significantly affected by a~ chemical. All three 

chemicals, however, produced some temporary visible effect. Emid retarded 

germination and early growth slightly. DNBPamine caused some yellowing 

and necrosis on the margins of the first two or three leaves. Yields, however, 

were not significantly affected by a~ treatment. 

The cost of the DNBPamine treatment would be approximately $5.20 per 

acre. The cost of the amino trialllole treatment would be approximately 

$3.40 per acre. If only a foot-wide band over the row were sprayed, the

72. 

cost would be on~ one-third of the above. 

Summary 

Amino triazole, 3/4 Ib./A., and DNBPamine, 3 Ibs./A., applied when 

sweet corn was about two inches high, gave good commercial control of 

annual grass and broadleaf weeds, when followed by tractor cultivation, 

without significant effect on plant stand or yield. Emid, 2 Ibs.!A., 

applied just after seeding, gave equal~ good weed control with no signi-· 

ficant effect on plant stand or yield. All chemicals, however, produced 

slight~ temporary stunting or injury which was quick~ outgrown. 

Table 1. Effect of ear~post-emergence applications of DNBPamine and 

amino triazole, and pre-emergence application of Emid, on yields 

and stand of sweet corn and on weed growth. 

Herbicide 

i 

DNBPamine I 3 

Amino triazole. 3/4 

Emid I 2 

Hoed check ; 

Unhoed check 

L.S.D. 5% 

I 

i I iWeight of i 

Date of 'Marketable Stand, lweeds per j Percent 

IRate, ; 

i Ibs./A., app1! qa- yield from plants 13 sq. ft. crabtion=/ 

4 plots, per 25 on 6/11, i' grass 

1active 

Ibs. it. £!!RS. on 6/11 

I 

1 

I 

6/2 

6/2 

5/23 

]/ Seeding date was May 23, 1958 

69.8 ! 42 ! 0.3 i 21 

69 •8 41 I 3 .1 i. 85 

69.8 I 43 0.2 40 

68.8 I' 47 0 

60.0 46 18.8 

i 

N.S. I N.S. 7.9 

I 

I 

I 

i 

71

STUDIESmTH PRE-PLANTING,PRE-EMERGENCE, ANI>POST-PLANTING 

APPLIC.:~TION OF HERBICIDESONCERTAINVEGETABLECROPS11 

Fred L. Bower II, and F. E. Chappell '1:/ 

Virginia .·;gricul ture Experiment Station - Blacksburg, Va. 

73. 

Four field experiments were set up in Blacksburg and a fifth in Grottoes, 

Virginia to test various chemicals at different levels of concentration on Upland 

cress (Barbarea vulgaris) and other crops. Cress is normally seeded in 

this area about &ugust 15 to September 15. Stands are often poor if dry hot 

weather is encountered. 

Experiments'I, II, and III were preliminary experiments seeded to cress. 

The treatments were arranged in a block design and each treatment was replicated 

four times. The preliminary experiments were designed to determine which 

chemicals would give the best weed control without inhibiting seed germination 

or reducing the vigor of the cress. 

Experiment IV was a field test of several herbicides as pre-emergence and 

pre-seeding treatments on several vegetable crops. Experiment V was a field 

test of pre-seeding and pre-emergence treatments on cress. 

Water and vermiculite were used as carriers. &11 sprays were applied with 

a knapsack sprayer using two 8004 TeeJet nozzles at a rate of 40 gallons of 

solution per acre. Vermiculite was used as the carrier in the granular treatments 

and was applied with a small hand duster. 

Experiment I - Pre-seeding and Pre-emergence 

Treatments used in pre-seeding and pre-emergence appear in Table 1•. 

Treatment I was black polyethylene plastic which was laid down on June 24, 

two weeks prior to seeding. The plastic covered the entire plot and was 

secured on all sides by wire wickets. Pre-seeding treatments 2 to 12 were 

CDEC, and DNOSBP&s sprays and CIPC as sprays and on vermiculite applied on the 

same date. 

The plastic was removed immediately prior to seeding. Pre-emergence treatments 

3 to 18 using sprays of CIPC, CDEC, and a combination of CIPC and CDEC 

were applied as soon as seeding was completed on July 3. 

Plots were rated for weed control on July 17. Results appear in Table ~. 

These studies were supported in part by grants from the Zonolite Company, 

The Du Pont Company, and The Columbia Southern Chemical Company. 

Graduate Research Assistant and Plant Physiologist

These treatments and the rate of active material in pounds per acre appear in 

Table 2. The pre-seeding treatments were made on August 1, two weeks prior to 

seeding. The cress was seeded and the pre-emergence treatments were made on 

AU2ust 16 

74. 

TABLE1 

Weed ControlRat~ngs For Experiment I . 

Treatments 1·12 Pre~seeding.· Applied June 24 

Treatments i3-18 Pre-emergence. ;~pplied July 3. 

CHEHICi~ UTE IN RATINGFOR 

POUNDPER ACRE 

JULY17 

1. PL/iSTIC 8.25 ·b c * 

2. CDEC (S) 4 8.25 bc 

3. CDEC (5) 6 8.75 a ·b 

4. CDEC (£) 8 9.50 a b 

5. cnc (5) 4 6.75 d e 

6. CIPC (5) 6 6.25 d e 

7. CIPC (S) 8 5.75 e 

8. DNCSBP (S) 3 9 a b 

9. DNC5BP (S) 4% 9.25 a b 

10; CIPC (G) 4 9.75 a 

11. CIPC (G) 6 10 a 

12. CIPC (G) 8 9.75 a 

13. CUC (5) 2 6.75 d e 

14. CIPC (S) 3 5.75 e 

15. CIPC (5) 4 7.25 c d 

16. CIPC-CDIl:C (5) 2-4 9.25 a b 

17. CDEC (S) 4 8.25 b c 

18. CDEC (S) 6 8.75 a b 

19. CHEC;{ 6.25 d e 

S - SPRi.y 

G - GR_i.NULAR 

10 - COMPLETECOrITRCL 

1 - NO COiITROL 

* Values in a column followed by the same letter are not significantly different. 

RESULTS 

The granular treatments tended to produce better weed control than the spray 

treatments. The 8 pound rate of CDEC. the 4%pound rate of DNOSBP.and the 

combination of 2 pounds of CIPC ~ith 4 pounds of CDECas sprays produced high 

levels o.f weed control. The possibility of these higher rates greatly reducing 

the germination of even the deepest placed seeds should not be discounted. No 

data ,..as collected on the crop as a heavy rai.· washed the seed out. 

Experiment II - Pre-seeding and Pre-emergence 

Experiment I involved the application of CIPC. CDEC. and Dl~('5BP as sprays 

and CIPC on Vermiculite as pre-seeding treatments. CIPC and CDECwere applied as 

sprays in the pre-emergence treatments.

The first weed control rating was made on August 27 and a second rating 

on October 7. Data are presented in Table 2. 

75. 

Weed Control Ratings For Experiment II 

Treatments 1-7 Pre-seeding. Applied August 1 

Treatments 3-10 Pre-emergence. Applied August 16 

~~ Ri.TE IN RATINGFOR RATIi~G FUR 

PCUNDSPER ACRE AUGUST27 OCTOBER10 

1. CDEC (5) 4 7.75 a b c* 2.75 b c 

2. CIPC (5) 4 5.25 d 1.50 c 

3. CIPC (8) 6 6.5 c d 1.25 c 

4. DNOSBP(S) l~ 6.5 c d 2.25 b c 

5. CNOSBP(S) 3 7.25 a b c 4 b 

6. CIPe (G) 4 8.25 a b 6.25 a 

7. CIPC (G) 6 3.5 a 7.5 a 

8. CIPC (S) 2 7.0 a b c 3 b c 

9. CIPC (5) 4 6.75 b c d 3 b c 

10. CDEC (S) 4 7.50 a b c 3 b c 

11. CRECK 6.5 c d 2.75 b c 

£ - SPR.'>Y 

G - GR.c.NULAR 

10 - COl1PLETECONTROL 

1 - NC CONTROL 

*Values in a column followed by the same letter are not significantly different. 

RESULTS 

Experiment II was rated for weed control, but not for crop Vigor or stand. 

The stand was irregular or non-existant in all plots due to climatic factors. 

In EJ~eriment I, CIPC on vermiculite at the 4 pound and 6 pound rates 

gave the best weed control. Evidence of this weed control was still apparent 

on October 10, 2~ months later. The equivalent rates of CIPC applied as sprays 

did not give equal weed control even 26 days after application, and by October 

10 the weed control on these plots was less than that of the check plots. 

Experiment III - Pre-emergence 

Experiment II was similar to Experiment I in that the same chemicals-were 

used, but all treatments were made as pre-emergence applications. 

Cress seeding -and treatment applications were conducted on August 29. 

Heed control ratings were made on October 10, but no crop vigor or stand ratings 

were made. Ratings were not made because of irregular stands or non-exisistence 

of stands due to climatic factors. 

lleed control ratings are presented in Table 3.

76. 

TABLE3 

~leed Control Ratings Fat' Experiment In 

Treatments Applied Pre-emergence 

CHEMICAL RATEIN RATINGFOR 

POUNDSPERACRE 

OCTOBER10 

i. CDEC (5) 4 7.5 b c* 

2. CIPC (5) 4 6.75 e 

3. CIFC (S) 6 6.75 e 

4. DNOSBP(S) 3 7.25 c 

5. DNOSBP(S) 4% 8.75 a 

6. CIPC (G) 2 7 b 

7. ClPC (G) 4 7.50 b c 

8. CI?C (G) 6 8.50 a b 

9. CIFC (5) 2 6.75 c 

10. CHECK 6.75 c 

S - SPRAY 

G - GRANULAR 

10 - COffi'LETECONTROL 

1 - NOCONTROL 

*Values in a column followed by the same letter are not significantly different. 

RESULTS 

The DNOSBPspray at 4%pounds per acre and the 6 pounds per acre of CIPC 

on the vermiculite gave the best weed control. 

Data concerning this experiment appear in Table 3. 

Experiment IV - Pre-seeding 

and Pre-emergence 

Experiment IV consisted of 16 treatments which were arranged in plots 20 

feet by 20 feet in sLze. Each plot was seeded to corn, lima beans, and green 

beans to which treatments were applied pre-emergent. Kale, spinach, cress, 

and tomatoes were seeded 2 weeks after the treatments were applied. 

In this experiment DNOSBP,£PTC.,SIMZAlN,CDEC,end NEBURONon liquid and 

granular carriers were used. 2,4-D was used on liquid carriers only. CDEC 

and DIURONwere used with attaclay as the granular carrier instead of vermiculite. 

All treatments were applied on May 30. 

The corn, lima beans, and green beans were seeded OD May 30 end the cress, 

kale. spinach. and tomatoes were seeded on June 12. 

Data concerning chemicals, rates the weed control ratings for July 1, 

July 17. and August 27. and the crop vigor rating for July 1 are presented in 

Table 3.

PARTI 77. 

TABLE4 

WeedControl (1) 

CHEMICAL RATEIII ·RATINGFOR RATINGFOR RATIl\1GFOR 

POUNDSPERACRE JULY1 JULY17 AUGUST27 

1. DNOSBP(5) 6 7 bed 6 bed 2.5 de 

2. DNOSBP(G) 6 8 abe 7 abc 4 bcde 

3. EPTC (S) 6 9 Ii 8ab 3 cde 

4. EiTC (G) 6 8.5 ab 8 ab 4.5 bcde 

5. CIPC (S) 4 5.5 d 2.5 f 2 e 

6. CIPC (G) 4 7.5 abc 5 ede 3 ede 

7. SIMAZIN(S) 2 9 a 9 a 8 a 

8. 5IMAZIN(G) 2 9 a 8 ab 6 ab 

9. CDEC (5) 6 8.5 ab 7 abe 4 bcde 

10. CDEC (G) 6 8.5 ab 7 abc 4 bcde 

n. NEBURON(S) 5 9 a 8.5a 6 ab 

12. NEDURON(G) 5 8 abe 7 abc 5 bed 

13. DIURON(8) 2 9 a 8.5a 5.5 be 

14. DIURON(G) 2 9 a 8 ab 6 ab 

15. 2,4-D (5) 2 6.5 bed 4 def 2.5 de 

16. CHECK 6.5 bed 3.5 ef 2.5 de 

Values in a eo1umn followed .by the same letter are not significantly different. 

Vigor 

PARTII 

Ratings For July 1 (2) 

Stand 

CHEMICAL f! Y SB g 1$ s z 

1- DNOSBP (5) 9 8 10 5 2 4 4 

2. DNOSBP (G) ·9 9 10 3 2 2 2 

3. EPTC (S) 8 6 10 6 2 9 5 

4. EPTC (G) 5 8 9 4 3 8 4 

5. CIPC (S) 7 7 8 8 2 8 4 

6. CIPC (G) 5 7 9 6 2 7 4 

7. SIMAZIN (S) 6 5 4 3 2 2 2 

8. SIHAZIN (G) 5 6 10 7 2 3 2 

9. CDEC (S) 8 6 9 7 2 9 5 

10. CDEC (G) 7 9 10 9 2 7 3 

11. NEBURON(S) 6 6 8 2 2 2 3 

12. NEBURON(G) 5 7 7 4 2 2 3 

13. DIURON (S) 5 5 5 2 2 2 2 

14. DIURON (G) 6 6 4 2 2 2 2 

15. 2,4-D (S) 7 6 6 6 2 3 3 

16. CHECK 7 9 10 5 2 3 4 

(1) - NOCONTROL., 10 - 100'7.CONTROL 

'- 

(2) - 1 - PLANTSDEAD,10 - EXCELLENTVIGOR 

CN- Corn; LB - Lima Beans; SB - Snap Beans; SP - Spinach, K ~ Kale; c - Cress; 

T _ "'n",:l!I.~naC!

78. 

RESULTS 

Experiment IV pointed up the fact that chemicals applied on vermiculite 

tend to persist longer than those applied as sprays except in the case of 

SIMAZIUand NEBUROl~. DIURONet 2 pounds per acre as a spray. and on vermiculite 

also produced good weed control over longer periods of time, as indicated by 

ratings made 8 weeks after treatment. 

Experiment V - Pre-seeding and Pre-emergence in Cress 

Experiment V was carded out on the farm of one of the larger coamercial 

cress grm~cra near Grottoes, Virginia. The seed and the seeder were supplied 

by the grower. Seeding was done on August 25. 

CDEC,DNOSBPas sprays and CIPC as sprays and on vermiculite were applied 

as pre-seeding treatments on August 14. CIPC. CDEC,and a combination of CIPC 

amd CDECwere applied as pre-emergence sprays on August 25. 

Data concerning this experiment appear in Table 5. 

TABLE5 

Weed Control and Vigor Ratings for Experiment V 

Treatments 1-9 Pre-seeding. Applied August 14 

Treatments 10-15 Pre-emergence. Applied Aug. 25 

CHEMICALRATEIN WEEDCONTROL VIGORRATED 

POUNDSPER ACRE RATEDSEPTEMBER15 SEPTEMBER15 

1. CDEC (S) 4 5 c d * 7.50 abc 

2. CDEC (5) 6 6.75 b 8.50 a b 

3. CIPC (5) 4 4 d e 7.75 abc 

4. CIPC (5) 6 4.25 d 8.75 a 

5. DN05BP(S) 1% 5.50 c d 7.75 abc 

6. DN05BP(5) 3 7.25 b 4.25 d 

7. DNOSBP(S) 4% 7.50 b 1 e 

8. CIPC (G) 4 8 a b 7 b c d 

s. CIPC (G) 6 9 a 4.25 d 

10. CIPC (5) 2 2 f 8 abc 

11. CIPC (S) 3 1 f 8 abc:: 

12. CIPC (5) 4 2.50 e f 8 abc 

13. CIPC-CDEC(5) 2 - 4 7 b 5 d e 

14. CDEC (S) 4 7.5 b 6.25 c d 

15. C~EC (5) 6 7.5 b 5.25 d e 

16. CHECK 1 f 8 abc 

S - SPRAY 

G - GRANULAR 

10 - COMPLETECONTROL;NOREDUCTIONIN VIGOR 

1 - NOCONTROL;DEATH 

*Values in a column followed by the same letter are not significantly different.

RESULTS 

79. 

In Experiment V the higher rates of the chemicals, in general, gave the 

best weed control. Exceptions were the pre-seeding treatments of CIPC as a 

spray at 6 pounds per acre, and CIPC spray at 4 pounds per acre as pre-emergence 

treatments. 

CIPC at 4 pounds per acre on vermiculite as a pre-seeding treatment, and 

CDECspray at 4 pounds per acre as a pre-emergence treatment were the only 

two treatments that gave acceptable weed control as well as a reasonably 

acceptable level of crop vigor. 

Pre-planting treatments of DNOSBPsprays at the higher rates greatly 

reduced vigor as did the application of 6 pounds per acre of CIPC on vermiculite. 

The combination of 2 pounds of CIPC with 4 pounds of CDEC,and the 4 and 6 pounds 

per acre rates of CDECas pre-emergence treatments also reduced vigor. 

SUMMARY 

1. Several herbicides were applied to various crops as sprays and on 

vermiculite. In general thecbemicals applied on vermiculite gave better 

control of weeds. 

2. CIPC at 4 pounds per acre on vermiculite as a pre-seeding treatment, and 

CDECat 4 pounds per acre as a spray gave acceptable weed control and good 

vigor of cress. 

3. The 4 and 6 pounds per acre rates of CIPC on vermiculite, SIMAZINat 2 

pounds per acre, NEBURONat 6 pounds per acre, and DIURONat 2 pounds per 

acre on attaclay and as sprays produced a high level of weed control. Sprays 

of CDECat 8 pounds per acre, DNOSBPat 4\ pounds per acre, and a combination 

of 2 pounds of CIPC per acre and 4 pounds of CDECper acre produced comparable 

weed control.

As for control of annual broadleaf weeds, the May9 ,application was very 

effective AA.rlv in th .. RA::IRon. hut tln AtUMJRt l' th ..,... WAR ~onRid..r"hlA 

80. 

Control of Northern Nutgrass and Other Weeds in Potatoes and Tomat~s 

in 19$8 

E. M. Rahn 

University of Delaware 

In a screen1ngtest on strawberries in 1957, EFTC (et~l N, N~di-npropyl-thiolcarbarmate) 

was found very effective in preventing geT)llination 

of tubers of northern nutgrass (Cyperus esculentus L.) withoutsJgnificant, 

injury to strawberries. In vie~' of the fact that nutgrass has,been seiious-' 

ly reducing yield and grade of potatoes for a number of growers, a preliminary 

exper:iment involving the use of EPl'C on potatoes was run in 1958 on soil 

heavily infested with nutgrass tubers. Also nearby, EPl'C along with a number 

of other herbicides mostly as granulars, were screened on tomatoes grown 

on soil heavily infested with nutgrass and crabgrass. 

Potato 

Experiment 

Delus potatoes were planted on April 18 on Norfolk 10al1\Ysand at the 

Georgetown SUbstation. Treatments (Table 1) were replicated four times in 

randomized blocks. Plots consisted of three rows 3 feet apart and 30 feet 

long. EPTC, as a 6 1,bs •/ gal. emulsifiable cone,ent,rate, was applied in a 

water spray at 50 gals./A. on two dates. The firet date was April 23, five 

days after planting. On this date the soil W~e wet and compact, 0.73 inches 

of rain having fallen the day previous. The second date ,of application was 

May9, twenty-one days after plaP.t~ng !~ one day after the ridges were 

"drug off" with a smoothing b~ftoW. On this date nutgrass was emerging pro 

'fuseJ#:.', The soil eurface, as a result of "dragging off",; was relatively dry 

and loose. All plots received tractor cultivati~ as needed. The hoed 

check p:J,.otswere, hoed when needed. 

Reeults 


EPTCwhen applied to dry, loose soil on May9 gave much better control 

of nutgrass than when applied to wet, compact soil on April 23. This is in 

agreement with experiments conducted by the manufacturer, which showed that 

EPTCapplied to wet soil is ineffective because of limited penetration of 

EPTCvapor into the soil. On June 11, a month after application of EPTC, 

10 Lbs./A., there was 95%control of nut grass (Table 1). On August 12, three 

months aft.er the same application, there was 88% control of nutgrass, indicating 

some regeneration of nutgrass. This was probab:J.y due to propagation of 

the few plants "missed" by' EPl'C as well as due to germination of nutgrass tubers 

late in the season whose dormancy was broken by late cultivation. The 

late growth of nutgrass caused significant injury to potato tubers - the nutgrass 

stolons grew through the potato tubers. Probably a second application 

of EPTCjust before or after the last cultivation would prevent this late 

growth of nutgrass. EPTCat 5 Ibs./A. was not significantly different from 

the 10 Ibs./A. rate.

81. 

crabgrass present due to germination after the 'last cultivation. 

Yields and plant growth were not affected b,y EFTCapplied ;on .May 9. 

I 

§ummary'and Conclusions,' 

EP'l'C, 5 and 10 lbs./A., applied just after "dragging-off" potatoes, followed 

~ tractor cUltivation, gave good control of nutgrass and annual grasses 

and broadleaf weeds up to three weeks after the last cultivation. After this 

date nutg:rl1.ss and crabgrass appeared to some extent. Yields and plant growth 

were not affected b,y these treatments. 

Table 1. Effect of ErI:C on yields of potatoes and growth of nutgrass and 

other lieedG.!! 

,Treatment 

EPTC, 5 lbs./A applied 4/23 

EPTC, 10 lbs./A. applied 4/~~ 

EPTC, 5 lbs./A. applied 5/9~ 

EFTG, 10 lbs./A applied 5/9 

Check, hoed 

Check, not hoed 

Yield, Dry Weed Control, Percent 

U.S.#l, Matter, 

Bu./A. % Nutgrass Broad- Annual 

leafs, . Grasses 

6/11 8/12 8/12 8/12 

343 

356 

396 

392 

441 

323 

16.8 

16.3 

16.1 

50 

50 

83 

95 

95 o 

35 

40 

78 

88 

93 

o 

33 5 

25 20 

80 43 

88 48 

90 18 

0 0 

L.S.D. - 5% 

88 

N.S. 

29 

41 

32 30 

1/ Pot~toes were planted 4/18 

y EFTCapplied just after "dragging-off". 

Tomato Experiment 

Treatments used are listed in Table 2. They were not replicated. Plots 

consisted of three rows 5 feet apart and 33 feet long. Vapamwas applied on 

April 25, fifteen days before planting. A furrow three inches deep was made 

in the rmv. Then the indicated amount of Vapamwas applied in water, 2 gals. 

per 100 feet of row, using a sprinkling can. The furrow was closed immediately 

and the soil surface was compacted b,y rolling to reduce vaporization 

to the air. 

Delaware 13-2 plants were set on May 10. All plots receive(Oi tractor 

cultivation throughout the season as needed. The hoed check plots were hoed 

as needed. All other plots were never hoed. All chemicals except Vapam 

were applied twice: on June 12, just after cultivation, and on July 2, just 

after the last cultivation. The ,granulars were applied over the plants with

Table 2. Screening of certain herbicides, most]y as grarmlar formulations, for full season weed control 

in tomatoes'!! in 1958 at Georgetown, Delaware. 

OJ. 

I\) 

%Weed control on -neeacontr61 on 

2' Rate, Market 6/30 8/12 

Chemi.cal~ Formulation Ibs./A. Yiel~ Nut- Ann. Broad- Nut- Ann. Broadactive 

Tons A. gr~s Grass leafs grass ...grass leafs 

EPrC 5% granular 

mc 5% grarmlar 

Diuron 

Diuron 

2%grarmlar 

2%granular 

Neburon ~ granular 

Neburon b%granular 

Simazine 1($ granular 

S:iJila.zine l{],t grarmlar 

DNBPamine· 1($ granular 

DNBPamine 1($ granular 

CDAA 1($ granular 

CDAA+DNBP 

amine la,t granular 

CDAA+DNBP 

amine 1~ granular 

Alanap- 3 20; granular 

Alanap-3 2($ granular 

ACP-M-460 Spray 

Vapam Drench 

Vapam Drench 

Hoed Check -------- 

UDhoedCheck-------- 

5 

10 

1 

2 

4 

6 

li 

3 

6 

9 

6 

3+3 

6+6 

3 

6 

4 

1 pt./100 l 

22.2 

20.3 

18.3 

10.3 

16.4 

14.5 

15.2 

9.3 

13.4 

11.8 

19.7 

18.9 

13.5 

2.8 

1.8 

2.4 

13.4 

13.0 

19.0 

14.9 

o 

50 

o 

50 

ooooo 

20 

o 

30 

30 

80 

90 

o 

o o 

90 

o 

o 

50 

50 

90 

40 

80 

20 

50 

60 

90 

100 

100 

100 

80 

90 

100 

o 

90 

o 

o 

50 

80 

100 

40 

80 

20 

50 

100 

100 

80 

100 

100 

80 

90 

100 

o o 

90 

o 

80 

100 

50 

80 

40 

40 

40 

60 

20 

10 

80 

20 

30 

20 

20 

o 

o o 

100 

o 

90 

100 

60 

100 

50 

60 

80 

100 

20 

30 

50 

40 

60 

o o 

100 

o o 

100 

o 

90 

90 

100 

100 

100 

100 

100 

100 

90 

90 

80 

100 

100 

80 

80 

100 

60 

80 

100 

o 

% Crop 

Inj'¥'l 

on 8/12 

o o 

10 

50 

o 

20 

50 

80 

10 

40 

o 

o 

60 

90 

100 

100 

10 

40 

o 

o 

1/ Tomato plants set into field on May 10. 

Y All chemicals except Vapam were applied to fresh]y cultivated soil on June 12 and Ju]y 2. Vapam was 

applied as a pre-planting in-the-row soil drench on April 25. 

( (

a Gandy spreader. ACP-H-460(2,5-diohloro-) nitro benzoic acid) was applied 

in an over-all water spray, 50 gals./A. 

The predominant weeds were nutgrass and crabgrass. There were a few 

annual broadleaf weeds: lambls quarters, pigweed, and ragweed. 

Results 


The on~ chemical in this test that gave full season control of nut grass, 

as well as annual weeds, without any plant injury and reduction in yield was 

EPTC(Table 2). On August 12, six weeks after the lay-by application of EPTC, 

10 Ibs./A., there was 10~ control of nutgrass and annual grasses, and 9afo 

control of broadleaf weeds. On the same date, where a 5 lb./A. rate of EPl'C 

was used, there was 8afocontrol of nutgrass, and 90%control of annual 

grasses and broadleaf weeds. 

SUIlI!llaI'Y and Conclusions 

Seven herbicides in granular "formulations, one herbicide as an over-all 

spray, and one herbicide as a pre-planting soil drench were screened for 

full season weed control, in combination with tractor cultivation, where the 

principal weeds were nutgrass and crabgrass. The on~ chemical that gave 

satisfactory weed control without any plant injury and yield reduction was 

granular EPTC. A rate of 10 Ibs./A. aotive gave near~ perfect weed control, 

while a 5 Lbs./A. rate gave commeroial weed control.

HERBICIDESFORTO'~TOES 1.2. 

by 

R. D. Sweet and Vincent Rubatzky 

Cornell Univeristy 

Growers of tomatoes in the Northeast are interested in weed control 

in tomatoes not only because of weed competition but also because a heavy growth 

of vreeds at harvest time greatly interfers with the harvest operati~. Also 

in some instances heavy weed Lro.~h may contribute to foliage diseases and fruit 

rot due to cutting down the circulation of air. Another aspect of chemical weed 

control is important where field seeding is practiced. In the lfortheast there 

is little commercial field seeding. However, growers are showing interest in 

this production practice but weed control when the tomatoes are small is very 

difficult. They are in need of a selective herbicide that will control several 

broadleaved species. 

REVIEWOF LITERATURE 

Several research workers have been active in testing chemicals against 

weeds in the presence of tomatoes. Danielson (1956) in Virginia and the writer 

and others have been intensively investigating this problem. It has been·generally 

concluded that Chloro IPC in granular form or, perhaps, as a liquid sprly 

can be applied safely'to tomatoes. However, high rates are not possible without 

causing damP.geand certain weed species such as lambs-quarters are very difficult 

to control with this chemical. 

Natrin (Zedler 1956) has been investigated by several workers. In the 

majority of cases there has been injUry reported. In certain areRs, sU0h as in 

NewYork state, there is much less injury reported. However, the chemical is 

not now being manufactured so regarcless of its merits a different material MUst 

be found. Dalapon has been reported as being good for weed control but in tests' 

by the writer and others there has been serious interference with blossom set 

and subsequent yields. llonuron has been used as a liquid and granular material 

with variable success. Frequently reduced yields have been reported. Simazine 

lfas used in 1957 by the writers. The l!Xcellent weed control warranted further 

investigations .nth this che~cal in spite of the foliage burn which occurred 

with the liquid sprays. 

EXPERIi'IENTAL Rh.SULTS 

The work reported here is in two main categories. First, the testing 

of newer chemicals against both the transplanted and seeded tomato crop and 

secondly, a comparison of liquid and granular formulations of existing chemicals. 

TESTSWITHj\1E\JERCHEMICALS 

The 1958 investigations with newer chemicals were conducted on a 

Dunkirk fine, sandy loam. Plants of the Red Jacket Variety were pulled on June 

l.Paper-No. 436 of the Department of Vegetable Crops. 

2. Part of this work was made possible by a grant from the Zonolite Corp.

85, 

loth but., due to excessive rainfall they vlere not transplanted until June 18th. 

During this eight day period the plants were heeled in under field conditions. 

Although the quality was excellent at the time of pulling the plants deteriorated 

somewhat during the heeling-in period. Plots consisted of single rows 15 

feet long containing seven plants each. There were two replications. July 1st 

the area was cultivated thoroughly and the chemicals applied in a two foot band 

directly over the row. Subsequent cultivations were limited to the row mid(1es. 

In Table 1 are presented the crop responses and weed ratings. From the table it 

can be seen that at the early dates all of the granular formulations were ~erforming 

quite well as far as lack of injury to tomatoes is concerned. Liquid 

sprays of KarmexW, Neburon, Dinoben, and lJiagara Experiment No. 4562 were outstanding 

in their Lack of crop damage amongst the liqnid formulations. 

Weeds consisted primarily of red-root, pigweed and tvlOannual grasses 

crab-grass and stink-grass (Eragrotis cilianensis). At harvest til.e weed control 

vias relatively good with a majority of the chemicals. Host of them were commercially 

acceptable. A notable exception was the :liagara material 4562. 

Yield records were taken. However, due to the relative small plant 

population and the fact that only two replications werE used, the yield data are 

of questionable value and therefore are not reported. 

To further evaluate the newer chemicals and their tolerance by tor'latoes, 

a direct-seeded test was started late in thesUIm,ler. Chemicals from the above 

test that showed promise both for tomato tolerance and for weed killing ability 

were included in this test. In this experulent the field was fitted, planted, and 

treated the same day. Individual plot,S were two rows, a foot apart, fifteen 

feet long. This gave a much hif)ler :>lant population than with the transplanted 

crop. There were two replications. At this late date there was little weed 

grol~h in spite of considerable showery, wet weather. Therefore, only the results 

on tonato grol~h are reported. Since granular formulations tended to 

perform l'lell in the transplant experiment, comparisons wer(; included between 

liquid and clay formulations in this direct-seeded experiment. In Table 2, the 

results are reported. Tomatoes show remarkable tolerance to Vegadex and the 

~~iagara Experimental naterial 4512. There was a marked difference between the 

liquid and clay formulations of Heburon and Simazine. It is interesting to note 

that in contrast to the relatively good tolerance of transplanted tomatoes to 

granular Chloro IPC applications, the direct-seeded crap is practically eliminated 

by this cheMical whether it is applied as a granule or as a liquid. 

In view of the lack of foliafe damage from the Niagara Experimental 

4562 when applied directly on the foliage of tomato and the evidence from other 

experiments which indicated that this chemical was quite toxic to broadleaf weeds 

and at high rates to arU1ual grasses, It was decided to expand the work with this 

chemical. It gave promise of being the first selective post-emergence chemical 

that vlould not harm tomato foliare but would be civing herbicidal activity to 

emerged vleeds. Several small tests were put on out in torato rerions of lvestern 

NewYork. In no case was the tomato foliage damaged. In one test there was a 

moderate stand of lambs-quarters about four to six inches tall. Four pounds of 

4512 killed lambs-quarters after about five days. 

&lall plots of 4512 were sprayed across variety tests of tomatoes. 

There seemed to be a very 'viele tolerance by thirty some varieties in the test.

86. 

Table 1- 

Tomato and I'feed RespOnSe{f 

Tomatoes 

~ds 

July 10 Au€,ust .5 August 5 

Chemical Lbs. 1 2 1 2 1 2 

1 Shell Lm7 3 5 9 8 8 7 6 

2 

II 

6 9 8 8 7 8 8 

3 Simazine 1 4 7 7 8 6 8 

4 

II 

li 9 7 8 8 8 9 

.5 Amchem460 4 6 6 8 6 8 7 

6 II 6 6 6 6 6 8 8 

7 

II 

503 4 2 5 2 2 6 6 

8 

II 

6 6 5 2 2 8 8 

9 Niagara 1-1512 4 9 9 8 8 6 7 

10 

" 

6 9 7 8 7 6 5 

11 

II 

4562 4 1 2 3 2 3 

12 

II 

6 2 1 4 1 2 3 

13 Natrin 3 8 8 7 8 8 8 

14 

II 

6 6 7 7 6 7 8 

15 Honuron 1 4 5 5 8 8 7 

16 

II 

It 2 3 6 7 6 8 

17 Neburon 3 6 7 8 8 6 7 

II 

18 4-~ 6 6 8 7 8 8 

19 Gen. C. 2603 1 5 6 5 7 7 6 

20 

II 

It 8 9 6 8 6 6 

21 

II 

2996 1 9 7 9 6 6 4 

22 

" l~ 7 9 8 8 7 7 

23 Sim. (Verm) 1 9 9 8 8 7 8 

24 

" It 9 9 8 9 8 8 

25 Sim. (C1a~) 1 9 9 9 7 8 8 

26 

II 11. 9 8 5 8 7 7 

2 

27 Neb. (Venn) 3 8 8 7 7 7 4 

28 

II 

4·~ 9 9 9 7 7 7 

29 II (Clay) 3 9 9 8 8 8 7 

30 

II 

4t 8 9 6 8 6 6 

31 Vegadex 3 9 9 8 7 8 7 

32 

II 

4i 9 9 8 8 7 7 

33 Check 9 8 8 7 4 3 

{f1=All tomato plants killed 7= Corr~ercial1y acceptable 9= Perfect plants 

1= Entire area heavil J 

r covered ~lith weeds 7= Commercial control 9= No weeds

Late eureser and early fall work in the greenhouse checking on compatibility 

of 4512 with commoninsecticides and fungicides indicates that greenhouse 

gro.m tomatoes under relatively low light conditions are muchnore sensitive 

than were field grown tomatoes of the same variety. Rates of four and six 

pounds per acre were not toxic under field conditions yet the rate needed to be 

lowered to about two pounds in order to prevent rather serious foliare scortch. 

To date the compatibility tests are not sufficiently complete to draw many conclusions. 

Hovrever, there is a marked difference in tomato response when the 

commonmaterials are combined with 4512. This may be a true chemical problem 

or it may be a formulation problem. This is an area where more work is needed . 

because in many areas tomatoes are freq1.1ently sprayed, particularly with funticides. 

Table 2. Direct-Seeded Tomato Responses 

Growth* 

Chemical Form. Lbs. 

--1- 2 

1 Vegadex Liq. :3 9 9 

2 

II II 

4t 9 9 

II 

:3 " 

6 9 8 

4 " 

Clay :3 9 8 

5 

II 

" ~i 

9 9 

6 

II II 

9 8 

7 Neburon Liq. 2 2 2 

8 

II 

" :3 1 2 

II 

9 Clay 2 8 9 

10 

II II 

3 9 8 

11 CIPC Liq. 2 2 2 

12 

II 

" 3 2 1 

II 

13 Clay 2 1 2 

ll~ 

II 

" 3 1 1 

15 Niagara 4512 Liq. 2 9 9 

16 

II 4 9 9 

17 " 

6 9 9 

18 

II 

" " 

8 9 8 

19 Simazine 1 1 1 

20 

II 

" l! 1 1 

21 

" 

Clay 1 9 8 

22 

II 

li 6 5 

23 Check 9 8 

II 

24 9 9 

*l=No tomato plants 7=Comrnercially acceptatle 9=Excellent Vigorous sto-nd. 

GP.AilULARVS LIQUIDFOil. 'Ul.Nl'IOiiS 

'-- 

To help evaluate more fully the value of granular versus liquid formulations 

of chemicals that showed possibilities in previous tests as herbicides 

for tomatoes, (Danielson 1953), an experiment was set up on a stony, slit loam. 

The same source of plants was used as described for the transplant experireent 

with n~~ chemicals. Plots were single rows 25 feet long, containing 12 plants. 

There were three replications. The dry materials were applied .dth a small hand

88. 

positive feed duster. The liquids were applied ;lith a small plot sprayer. In 

each case the chemical was applied directly over the crop row in a swath approximately 

three feet \v.ide. As in the other transplant test, the crop was cultivated 

and then treated immediately. No hand hoeing was done. The row middles 

were cultivated as required to reduce weed populations later in the season. The 

first ratings of crop response were made about ten days following treatment. 

The second crop rating was made three and one-half weeks later. The l'leed ratings 

were nade at the time of the second crop rating. These results are presented 

in Table 3. 

Table 3. 

Tomato and WeedResponses to Granular 

and Liquid Herbicide Applications. 

Tomatoes 

loTeeds 

July 10 !Ugus~ August 4 

Chemical B;:J;.. 1 2 3 1 2 3 1 2 3 

===:::::n::m::: ,....... =='.==r= 

1 Natrin liq. 3 9 6 8 8 7 6 7 8 6 

2 

" " 

6 8 8 8 9 7 0 8 8 7 

3 Simazin 

" 

1 6 6 7 7 8 7 8 8 8 

4 

" " l! 6 8 6 6 7 8 8 '8 7 

5 Hon. 

" 

1 3 2 5 7 6 6 8 8 5 

6 

" " l! 2 2 4 5 5 6 7 8 8 

7 Neb. 

II 

3 3 5 6 5 6 8 7 8 8 

8 

II 

4! 3 3 3 6 7 6 8 8 7 

9 Sim. Clay 1 8 8 8 9 7 8 7 7 7 

10 lJ.. 

" " a 7 6 8 9 7 7 8 8 7 

11 

II Verm. 1 7 8 8 7 8 8 8 8 8 

12 

II II 

l! 8 7 7 8 8 8 8 8 8 

13 110n. 

II 

1 4 7 7 7 6 7 7 7 7 

II II 

14 l! 4 5 6 6 7 8 8 7 8 

15 Check 9 8 9 8 9 8 5 5 5 

16 Neb. Clay 3 8 7 9 9 7 8 7 7 6 

17 41-· 

" " 7 8 8 8 7 8 7 8 

~ 

7 

18 

II 

Verm. 3 5 6 7 8 8 8 6 8 8 

II 

19 

" 

4t 4 5 6 1 8 8 8 8 8 

20 Check 9 8 8 9 9 8 4 5 6 

By referring to Table 3 one can readily see that the granular formulations 

were always less harsh than the same rate of chemical applied as a liquid 

spray. Except for the Neburon material Vermiculite was as satisfactvry as clay 

for a carrier. \Iith Neburon, houever, there was less crop damage from the clay 

formulations. This may be due to the fact that particles of vermiculite are 

angular and since with the wet season the foliage stayed relatively moist most 

of the time, considerably more vermiculite than clay remained on the tomato 

foliage. It should be pointed out, however, that this may not be the fundamental 

answer to these observations. By referring back to Table 2 one can see that 

clay fOrITlllations of Neburon are much safer on direct-seeded tomatoes than are 

liquids. This obviously cannot be a foliage absorption phenomena since the materials 

were put on at pla,nting time. A subsequent test l'JaS set up in the laboratory 

to help check on this point and it will be discussed later in the paper.

From the field tests with both transplants and direct-seeded tomatoes 

there were marked differences in crop response to granular and liquid formulations. 

However. two of the most oromisilll! Qaterials. Simazine "nn N",hl1,.nn.

90. 

to" "try to determine under somewhat more oontrolled conditions the reasons for 

the superiority of the granular formulations and to deternine whether or not 

the lack of damage to the transplants '\-rasjust due to a form of depth protection. 

\Jith both Simazine and Neburon the solubility is extremely low. This might 

mean that with normal rainfall the transplanted cr~p roots never encountered 

active chemical and therefore it is just anvescape'' that permits the use of 

these chemicals on tomatoes. 

In the greenhouse a factorial experiment was set up in small flats 

filled ~nth regular greenhouse potting soil to a depth of two inches. Seeded 

tomatoes trer-e used. The following treatments were included: 

1. Two depths of seedingl one-half inch and one and one-half inches. 

2. Twomethods of applying the chemical: a normal surface application 

and a thorough mixing in bfthe chemical. 

3. THOformulations: a standard liquid spray and a clay granular 

carrier. 

4. Twomethods of watering: regular surface sprinkling and one 

inch of water applied for three conseoutive days, then regular 

watering. 

5. Twochemicals: Simazine and Neburon. 

There were four replications ,'.ith fifty seeds for each treatment. 

In Table 5 are presented data on the plant emergence and the plant 

survival. The data were combined for the shallow and deep plantings because 

there was no difference in'this treatment, thus making 100 plants possible for 

each observation. As might be expected, the inch of water for three consecutive 

days had a bad effect on germination regardless of treatment. Generally speaking, 

the germination for all treatments that got normal watering was fairly good. 

There was no consistent difference in germination of the crop between Simazine 

or Neburon, between liquid or granular formulations or whether the chemical had 

been incorporated in the soil or applied on the surface. However, after a f~f 

days the plants began to die in some of the treatments. Final survival counts 

were made approximately three months following treating. It '\-rasfelt that after 

this time in the relatively restricted root area no tomato seeding lIould have 

escaped contacting active ohemical if it were present. As can be seen in 

Table 5 there ~s essentially no survival from the Simazin treatments regardless 

of the method of applying the chemical or the formulation used. '.'1ith Neburon it 

was quite a different story. Generally speaking, the clay formulation tended to 

be less toxic than did the conventional liquid formulation. However, there was 

an interaction with the method of watering and the method of incorporation. No 

satisfactory explanation can be offered by the author for these results, but 

they do indicate that Neburon in a clay formulation is not behaving the same as 

is the liquid formulation. On the other hand, Simazine eventually gives the 

same type of injury to t.onat.oee whether on clay or as a liquid. Whenon clay 

and applied on the surface the reaction to Simazine is delayed. Under field 

conditions ,"lith transplants the tomato may frequently escape damage from Simazine 

if it is applied as a granular on the soil surface. 

The above data reopen the question 

of whether or not the lack of

( 

TABLE5.GERMINATION AiIDSURVIVALOFTOMATOES IN GREENHOUSE TEST. 

Rep. 1 2 3 4 Totals 

Treatment Germ. Surv. Germ. Surv. Germ. Surv. Germ. Surv. Germ. Surv. 

1 Neb. Inc. liq. reg. 95 0 90 0 90 0 95 0 370 0 

n 11 11 

2 lea. 43 50 63 69 39 60 44 73 189 252 

11 

3 " Clay reg. 95 75 75 60 99 82 51 83 320 300 

4 'I n 

" lea. 60 7 52 13 43 3 71 24 226 47 

11 

5 Surf. liq. reg. 86 1 94 0 89 0 88 13 357 14 

6 

.. tr 

" lea. 78 0 61 0 41 0 46 0 226 0 

7 " " clay reg. 92 24 93 46 67 24 100 18 352 112 

11 

8 " " lea. 92 8 67 26 30 0 49 10 238 44 

9 Sim. Inc. liq. reg. 84 0 90 0 73 0 54 0 301 0 

11 

10 " 

" lea. 54 0 46 0 50 0 82 0 232 0 

11 " " clay reg. 97 0 96 4 92 0 95 0 "380 4 

It 

12 " " lea. 55 0 74 1 70 3 58 0 257 4 

13 " Surf. liq. reg. 95 . 0 95 0 91 0 86 0 367 0 

11 

14 " " lea. 63 0 80 0 32 0 72 0 247 0 

15 " " clay reg. 93 0 89 0 78 0 98 0 358 0 

16 " " " lea 67 0 53 0 28 0 79 1 227 1 

*Total plant emergence after two weeks for shallow and deep plantings (50 seeds each) are recorded 

as "germinat ion" • Survival counts were made three months later. 

92. 

to Ver~.liculite is really cue to difference in foliare absorption. At this point 

it seems entirely possible that clay granules are also in aor:.e~ray cutting down 

the chance of root absorption. The above test is inconclusive in this r~gard 

and further work needs to be done. 

SUMHARY aNDCONCLUSIOlJS 

From these tests it appears that of the newer chemicals Niagara Experimental 

No. 4512 offers promise as a post-emergence spray .dth excellent activity 

against emerged broadleaved weeds such as lambs-quarters. Field grown 

seedlings and transplants showed.remarkable tolerance of 4512. 

Granular formulations cpntinueto show excellent advantaees over conventional 

1iqnid sprays in crop safety and ease of application. 

Hateria1s such as Heburon, .Simazine and Vegadex Lookpromfatng on 

transplants as ~leed preventatives. Vegadex and Neburon granu1ars look very good 

on field seeded tomatoes. 

Hore work is needed :t;odetermine whether or not clay granules are 

changing the true activity of Neburon. 

REFEREHCESCITED 

Danielson, L. L., Preliminary weed control trials on the dry application 

of 3-Ch1oro-IPC impregnated clay granules. Va, Truck Agr. Exp, Sta. Vegetable 

Gr'otrer-sNe~TS. Vol. 7, iTo. 11, Hay 1953. 

Danielson, L. L. The Effect of Granular Herbicides on Yields of 

Tomatoes and Sweet Potatoes. Proceedings of '~~C 1956:p 116-121. 

Zedler, R. J. Su[gestions for using Experimental Herbicide Natrin 803 

in Tomatoes. Proceedings of NEI.'CC1956; p122-123.

93. 

ANEVALUATIONOF GRANULARANDSPRAYAPPLICATIONSOF 

HERBICIDESONYIELD ANDPROCESSINGQUALITYOF 

TOMATOES 

William F. Meggitt l and Charles Moran 2 

Several herbicides have shown promise for controlling 

weeds in tomatoes after the last cultivation. Although 

weeds coming in at this time will not in most cases reduce 

yields, they are a deterrent factor in harvesting. If harvesting 

is halted prematurely or delayed because of weeds 

or if marketable fruits are overlooked, then yields will 

be reduced. 

Some of the herbicides which have shown promise in 

certain experiments have failed in others due to lack of 

weed control or injury to tomatoes. It is felt further 

information is needed on these herbicides to determine 

their behavior under a range of environmental conditions. 

Further to be completely satisfactory for use in tomatoes, 

a herbicide must not only control weeds without injury and 

sUbsequent yield reduction, it must not impart undesirable 

flavor or delay ripening. 

The purpose of this study was to evaluate several 

herbicides applien as aqueous sprays and on granular carriers 

for controlling weeds in tomatoes, to measure the 

response of the tomatoes to these herbicides and to determine 

the effect, if any, on flavor, color, and acidity 

of the processed tomato products. 

PROCEDURE 

These studies were conducted in two locations: one 

at New BrunSWick, New Jersey on a Sassafras sandy loam 

soil and the other in Rancocas (Central Jersey) on a Woodstown 

sandy loam soil. The Rutgers variety of tomato was 

grown at New Brunswick and Campbell 146 at Rancocas. Plant 

spacings were 3 feet by 6 feet and 2 feet by 5 feet respectively. 

Plot sizes were 4 rows by 10 plants and 4 rows by 

12 plants each. The experimental design at both locations 

was a randomized block with 4 replications. 

Plants were transplanted into the field on May 28 and 

May 17, 1958. Regular fertilization and cultivation practices 

were made, and all plots were handhoed and weed-free 

at the time of treatment. 

lAssistant Research Specialist in Weed Control, Farm 

Crops Dept., Rutgers-The state University, New Brunswick, N.J.

94. 

At New Brunswick the following herbicides were applied 

on July 23, 1958: 

Ethyl N,N-di-n_propylthiocarbamate 

pounds per acre 

(EFTC) 4 and 6 

2-chloro-4,6-bis-(ethylamino)-s-triazine 

It and 3 pounds per acre 

(Simazin) 

1~n-butyl-3-(3,4~dichlorophenyl)-1-methyl 

. (Neburon) 2 and 4 pounds per acre 

urea 

2,5-dichloro-3-nitrobenzoic 

4 pounds per acre 

acid (Dinoben) 2 and 

4,6-dinitro-ortho-secondary 


butyl phenol (DNBP) 

isopropyl-N-(3-chl6rophenyl) 


carbamate (CIPC) 

EPTC, s Lmaz'Ln, and nebur-on were applied as a spray 

in 20 gallons of water per acre and on a .granular carrier 

(attaclay). Dinoben, DNBPand CIPC were applied only on 

the granular carrier. All spray applications were made 

with a 3 nozzle boom over the top of the plants. The granular 

applications were applied ,,':~ broadcast with no effort 

being made to keep the herbicides off the tomato plants. 

The soil was moist at the time of application. 

At the Rancocas location six herbicide treatments 

were made on JUly 18, 1958. They were EPTC, spray and 

granular, 5 pounds per acre; neburon spray 3 pounds per 

acre; simazin spray 2 pounds per acre; CIPC granular 8 

pounds per acre; and DNBPgranular 6 pounds per acre. 

RESULTSANDDISCUSSION 

The weed control and tomato yield for both locations 

is shown in table 1. . At New·Brunswick the weeds were slow 

in making regrowth after the last cultivation. However, 

observations made early in September showed considerable 

numbers of pigweed, lambsquarter, flower-of-an-hour, crabgrass, 

carpet weed and purslane. The percent weed control 

shown in table 1 for New Brunswick is the average of estimates 

made independently on September 26 by three evaluators. 

The data for weed control for the Rancocas location 

are actual weed counts per 15 square .foot area. The major 

species ~ere were crabgrass, pigweed, ragweed, and chickweed. 

The weed control obtained from all herpic;1.de treatments 

was highly satisfactory. EPTC spray at 4 pounds per 

acre gave a slightly lower percent control.on both proadleaf

95. 

Table 1. The effect of herbicide applications at layby on 

weed control and yield of tomatoes. 

Rate Method of New Brunswick Rancocas 

Herbicide Lb/A Appl1ca- %Weed Weed count! 

t10n Control Yield 15 sq. ft. Yield 

Broad- Tons/ Broad- Tons/ 

leaf Grass Acre leaf Grass Acre 

EPTC 4 Spray 88 87 16.2 

5 -- -- 6.2 2.2 24.1 

6 88 96 15.3 

4 Granular 92 90 16.5 

5 5% ---- 3.2 2.5 24.0 

6 93 90 17.6 

Neburon 2 Spray 96 87 14.5 

3 -- -- ---- 0.0 3.8 21.0 

4 95 83 10.6 

2 Granular 90 89 16.7 

4 4% 93 92 18.7 

Simazin It Spray 97 90 15.6 

2 0.2 2.8 13.0 

3 93 97 12.1 

It Granular 85 92 14.8 

3 8.5% 90 93 16.1 

CIPe 8 Granular 

5% 

99 98 15.2 2.2 1.5 24.3 

DNBP 6 Granular 

6% 

99 90 12.7 0.5 3.2 20.5 

Dinoben 2 

4 

Granular 

10% 

95 

99 

95 

96 

15.9 

16.6 

Handweeded Check 

Nonweeded Check 

15.4 

15.2 

5.8 14'.8 23.3 

L.S.D. .05 NS NS 4.0 

.01 NS 

3.4 

4.7 

3.3 

4.6 

3.1 

4.2 

and grass species than several of the other materials. The 

high broadleaf count at Rancocas in those plots treated with 

EPTC spray was due to common chickweed which germinated late 

in the season.

96. 

The yields presented in table 1 show a significant reduction 

for neburon spray at 4 pounds per acre at New 

Brunswick and a tendency toward reduction at 3 pounds per 

acre at Rancocas. The apparent reduction in yield was not 

evident in treatments made on granular carriers. Simazin 

spray at 2 pounds per acre at Rancocas produced a highly 

significant reduction in yield. The reduction for the 3 

pound spray treatment of simazin at New Brunswick approached 

signif1cance at the 5 percent level. DNBPgranular showed 

a tendency to reduce yields at both locations. Although not 

significantly lower than the handweeded check. yields from 

DNBPwere significantly lower than EPTC at both locations. 

neburon granular at New Brunswick. and CIPC granular at 

Rancocas. 

Observations 48 hours after treatment showed some foliage 

injury from all spray applications. The injury from EPTC 

was manifest as necrotic spots on the leaves but this was 

quickly outgrown. Injury from neburon and simazin spray 

was indicated by chlorosis of leaves with subsequent defoliation. 

The defoliation in the Rancocas test from simazin was 

quite severe. DNBPgranular although applied when plants 

were dry produced considerable foliar burn. There was no 

observable injury to foliage from any of the other treatments 

made on granular carriers. Lack of foliar injury 

from granular applications of EPTC. neburon. simazin and 

CIPC indicate they are considerably safer than sprays. 

Fruit size was reduced significantly by simazin in 

the Rancocas test. The apparent reduction by neburon 

neared significance at the 5 percent level. Using the 

number of fruit per 35 pounds as a basis. the check had 

102. simazin 136. and neburon 112 fruits. All other treatments 

ranged from 102 to 108 fruits per 35 pounds. 

Samples of fruit from all treatments were taken from the 2nd 

harvest. August 18. at Rancocas for processing and sUbsequent 

taste panel tests. color evaluations. and acidity determinations. 

The flavor evaluation of the processed puree was a tri- 

. angular test comparing the check with EPTC and CIPC in 

separate tests using six judges and six replications. Since 

this test is qUite involved. only EPTC and CIPC wereevaluated 

as they have appeared the most promising in tests in 

1957 and 1958. There was no objectionable flavor detected in 

either EPTC or CIPC treated samples. 

The titratable acidity of canned p~ree from the simazin 

plot samples of the August 18 harvest was higher than that 

of other treated samples. A mean of 6.6 milliliters of N/lO 

sodium hYdroxide was reauir~rl t,{) 1'1","1".",,,,1-1'7.'" 1() "" "f' f'~'+-~~~'"

puree from the simazin samples. The check sample required 

5.8 milliliters and the other samples ranged from 5.8 to 

6.2. This increase in acidity for simazin was significant 

at the 5 percent level and may be attributed to the smaller 

fruit size. 

Color indexes of safuples from both EPTC treatments were 

somewhat lower than those of other samples. Mean Hunter 

Color Difference meter indexes of A/2.5B fer the various 

treatments were: neburon, 66.8; simazin, 66.1; CIPC, 67.4; 

EPTC spray, 61.6; EPTC granUlar, 62.8; DNBP, 67.3; and 

check, 64.5. The difference required for significance at 

the 1 percent level is 3.1. The reason for the apparent 

color difference is unknown and further evaluations need to 

be made. 

Of the materials evaluated for weed control at layby in 

tomatoes EPTC and CIPC appear the most promising after two 

years evaluation. Neburon and simazin granular should be 

evaluated fruther since these compounds have shown a tendency 

to produce injury and to reduce yields when applied 

as sprays. Dinoben after only one year of testing shows 

extreme promise when applied on a granular carrier. 

The effects of these and other chemicals on quality factors 

should be further compared at all harvest dates. 

SUMMARY 

1. Six herbicides applied as aqueous sprays and on 

granular carriers were evaluated for weed control in tomatoes 

after the last cultivation at two locations in New Jersey. 

The effects of these herbicides on tomato yield, fruit size, 

flavor, color and acidity were also determined. 

2. Granular formulations of EPTC, CIPC, dinoben, simazin, 

and neburon and aqueous sprays of EPTC provided satisfactory 

weed control with no reduction in yield of tomatoes. 

3. Simazin spray at 2 and 3 pounds per acre produced a 

significant reduction in yield and fruit size. Neburon 

spray at 4 pounds gave a significant reduction in yield, 

and 3 pounds tended to produce lower yield and smaller fruit. 

4. There was no objectionable flavor in the tomato puree 

from treatments of EPTC and CIPC, the two herbicides evaluated 

in the taste panel tests. 

5. None of the herbicides evaluated except slmazin produced 

any effect on titratable acidity of canned pureee. 

EPTC tended to produce a lower color index than other herbicide 

treatments.

98. 

b. weec,s coru ng in after the last cu.rt.avat.t.on did not 

reduce yields but were a deterrent factor in harvesting. 

I. .. ·"'lr.,J.la:!:'formulations were much safer than aqueous 

sprays in that yields were reduced and foliage injured by 

sprays but not by granular applications. 

8. Granular formulations were equal to sprays in weed 

control and in some instances appeared to produce a longer 

lasting control.

CHE'rc"LS FOIl.v1EE!JIHGCAR~ 10TSl. 

99. 

by 

R•. D. Sweet, Vincent Rubatzky", R.Romancwski 

Cornell University 

For approximately twelve years carrot growers have used Stoddard 

Solvent as a selective post-emergence'herbicide. The material is very effective 

on a wide range of annual weeds, both broadleaves and grasses. A few notable 

exceptions are ragweed, galensoga and henbit. Carrots are tolerant of widely 

different dosages.· Since this material is used undiluted, a rather high 

gallonage of liquid must be handled for each acre. This means storage andhandling 

problems of a very practical nature at the farm. Another disadvantage of 

Stoddard Solvent is that there is always a potential fire hazard from smoking, 

engine exhaust, etc. 

For the above reasons research workers continue to look at newchemicals 

to see if they have possibilities for use on carrots. Several tests were 

conducted on a ~{irk fine sandy loam and on the muck soils of NewYork during 

the 1958 gro\dng sea~on. The first test was mineral soil in which the land 

,las fitted, planted and treated June 16, 17, and 18. Plots were two rows 15 feet 

long. Each treatment was replicated twice. In Table 1 are presented the chemicals, 

rates and ratillgs for carrot growth and weed control. It is interesting 

to note that the gr~at majority of chemicals did not harm the carrots. The 

Triazine derivatives Here a notable exception. Also there was some damaee in 

one replication from 2,4-D butyric. In this test ACPDinoben (u-46o) Stauffer's 

EPTAH,and the high rate of Ch10ro-IPC gave outstanding weed control. The predominant 

species involved were lambs-quarters, crabgrass, red-root and a few 

plants of nutLrass. 

A post-emergence application was made on carrots also planted on June 

17th in an adjacent area. In this second test the weeds were two to four inches 

tall, the carrots had two true leaves arid were generally considered to be at the 

stage the average erower treated his fields. From a research standpoint it was 

considered a little bit late for best results with Stoddard Solvent. The results 

are presented in Table 2. Again, the majority of chemicals did not harm 

the carrots. However, the ACP Dinoben did give significant stunting at the 

hibher rate. It is also interesting to note that this ch~nical was not so effective 

on established weeds as when applied pre-emergence. Chloro-IPC, EPTAlI, 

and others also failed to give acceptable weed control. Stoddard Solvent was one 

of the very befit treatments from both the weed control and crop tolerance 

standpoint. On the other hand, tuo compounds from Niagara No. 4512 and No. 4562, 

gave substantially better weed control in this test than they did when applied 

pre-emergence. 

l/hen the carrots trom the better weed control plots were approaching 

marketable condition, they 'tlere dug and the roots judged for strairhtness, size 

and taste. There seemed to be no bad effects from any of the ne\'l' compounds as 

far as carrot root developr,lent was concerned. Of course, where the top growth 

had been stunted b'J an injurious chemical early' in the season there was reduced 

growth at harvest time.

100. 

Table 1. Carrot and ieed rtesponse!l 

to Chemicals Applied at P1antin(. 

Carrots 

Heeds 

Chemical Lbs , 1--'2 1-- 2 

1 Niagara 4512 2 9 9 5 5 

2 

" " 4 9 9 6 6 

.3 " " 

6 9 9 7 6 

1I Hiarara 4562 2 9 9 7 6 

5 

" " 

4 9 9 6 8 

6 II It 6 7 8 9 9 

7 Amchem 1160 2 9 9 8 9 

It 

8 4 9 8 9 9 

It 

9 6 

" 

7 9 9 9 

10 Stauffer 16072 2 9 9 7 6 

11 

" " 4 9 9 7 9 

12 

" 

6 8 9 9 8 

13 

" 

Eptam 4 9 9 7 8 

14 

II It 6 8 9 8 8 

15 Geigy 30027 1 1 1 9 8 

16 II 

17 

" 

" 

2 1 1 9 9 

It 

4 1 1 9 9 

18 

II 

.30028 4 2 2 9 9 

19 6 2 1 

" " 9 8 

20 II It 

8 1 1 9 9 

21 Shell 4777 2 8 9 8 6 

22 

" " 

4 8 8 5 7 

23 

" 

It 

6 9 9 6 8 

24 H&B 2.h ..D-B 1 7 8 8 7 

25 

" " 

2 5 9 7 7 

26 GIPC 2 9 9 6 6 

27 

It 

4 9 9 9 9 

28 Stoddard Solvent 75 gal. 9 9 5 5 

111 = 100% heavy weed cover 7 = comraercial control 9 '" no l1eeds 

1 '" Complete crop kill 7 • commercially acceptable 9= perfect gro.rth 

Another series of tests on the Dunkirk fine sandy loam l~as started on 

July 21st. An area l

Table 2. 

Carrot and WeedResponse to Chemicals 

Applied Post-emergence. 

"-' Carrots vTeeds 

Chemical lbs. 1 2 1 2 

101- 

1 Niagara 4512 4 8 8 8 8 

2 

II II 

6 8 7 8 8 

II 

3 4562 4 7 7 8 8 

II 

4 " 

6 8 7 8 9 

5 Amchem 460 4 7 8 3 4 

6 

II II 

6 6 7 6 5 

7 Stauffer 1607 4 8 8 7 6 

8 

II II 

6 9 9 3 4 

II 

9 Eptam 4 9 9 5 3 

10 

II II 

6 9 9 6· 4 

11 CIPC 2 9 9 6 3 

12 

II 

4 9 9 6 6 

13 2,4,D-B 1 7 7 7 4 

14 Vegadex 2 9 9 2 4 

II 

15 4 8 9 6 4 

16 Stoddard Solvent 75 gal 9 7 8 9 

17 Shell 4777 4 7 8 7 3 

18 

II 

" 

6 9 8 2 3 

Table 3. Carrot and WeedResponse to Chemicals Applied at Planting (2nd Test) 

Carrots ~ 

Chemical 1bs. 1 2 1 2 

1 Niag~ra- 4512 2 9 8 6 6 

2 

II II 

4 8 8 7 7 

II II 

3 6 8 8 8 7 

II 

4 4562 2 7 8 8 7 

II II 

5 4 6 6 8 8 

6 

II II 6 6 6 9 8 

7 Amchem 460 2 8 8 8 8 

8 

II II 

4 7 7 9 9 

II II 

9 6 6 5 8 8 

10 Stauffer 1607 2 8 9 6 4 

II II 

11 4 7 9 7 6 

12 

II II 6 8 8 8 7 

13 Gei£y 30028 

1,. 

2 4 4 7 7 

II II 

14 1 2 3 8 8 

II 

15 " 

2 1 2 8 8 

16 Stauffer Eptam 4 8 9 7 7 

II II 

17 6 7 8 8 8 

18 CIPC 2 9 9 6 6 

II 

19 4 8 9 7 7 

20 M&B 2,4,D-B 1 2 1 8 8 

21 

II 

" 

2 1 1 9 8 

~2 Vegadex 3 9 9 4 5 

II ~3 41,. 9 9 6 5. ___ 

2 

~

102. 

CHEMICALSONMUCK-GROI'NCARROTS 

In the test on muck all plots 1,rere one row, 20 feet long with three 

replications. The field was disked, fioated and planted one day and the treatments 

'!'rere applied the next. In Table 4 are recorded crop and weed responses as 

of July 18th, about two weeks following treating. From the table it can be seen 

that again Acp-460 perforned well. The two Experimental Niagara materials were 

weak on weed control. The high rate of Vegadex whether liquid or granular tended 

to be toxic to the carrots. In contrast to results on mineral soils the Chloro 

IPC l-1aS not particularly effective in weed control, perhaps due to the relatively 

low rates for muck. Another outstanding differential perfonnance was the 

Triazine derivative 3002'8. On IIlIlcksoils this compound gave excellent control of 

weeds without damage to the carrots. EPTAMperfonned well both on muck and on 

the mineral soil. 

Table 4. Carrot and Weed Response to Chemicals 

Applied at Planting. (Muck So11) 

Carrots 

lIeeds* 

Chemical lbs. ave i Reps. aveT!ieps 

1 Amchem:460 2 7 

2 

II II 

4 8 7 

II II 

3 6 8 7 

4 Niagara 4512 2 8 4 

II II 

5 4 8 4 

6 

II II 6 8 4 

II 

7 4562 2 9 5 

8 

II II 

4 8 5 

II II 

9 6 8 6 

10 Shell 4777 2 8 3 

11 

II II 

4 8 5 

12 

II II 

6 7 5 

13 Ve~adex 3 6 7 

II 

14 8 8 

II 

15 

~i 

6 8 

16 CIPC 2 8 II 

17 3 8 4 

18 

II 

4 8 4 

19 Geigy 30028 1 8 7 

20 

II II 

2 8 7 

21 

II II 

3 8 8 

22 Eptam 3 8 7 

II 

23 4! 8 7 

II 

24 6 7 6 

25 Stoddard Solvent 75 gal 9 3 

26 Check 9 3 

*No chemical controlled barnyard grass. 

On July 24th approximately three weeks after planting a section of untreated 

carrots was treated post-emergence with chemicals that had shown promise 

poat-emergence on mineral f'oj,la. Here, again, plots '!'rere one row, 20 feet long 

~. 

with three repli(,-ll.tions. In Table 5 OTll" CAn ""0 t.hllt,iIli"'e;l,rc. F;xpa ....;'"~'""'."l. h562

103. 

was harsh on the carrots at the higher rates. Also the 2,4,D-Butyric was not 

safe. In this post-emergenee test the EPTAMderivative 1607 and the Chloro IPC 

were ineffective on the several weeds present. The latter did control purslane, 

however. The important vleeds vrere·red-rrot, pigweed and barnyard grass with 

some purslane. There was an extremely heavy infestation of barnyard grass. No 

chemical except Stoddard Solvent controlled barnyard grass. Co~equently, from 

a practical standpoint no material was as satisfactory as Stoddard Solvent postemergence 

with the weed papulation that was present in these plots. If barnyard 

grass ,"lere excluded, however, the hilhel',' r.ates of Niagara No. 45l2and No. 4$62 

and Geigy 30028 showed good performance. 2,4,D-Butyric did not control purslane. 

.~·J."i'-·: 

Table 5. Carrot and Weed Response to Chemical.s 

Applied Post-emergence. (Muck Soil) 

Carrots 

Weeds 

Cheniical Ibs. . ave. j Reps. ave. 3 :Reps. 

1 Niagara 4512 2 8 3 

2 

II II 

4 1 6 

3 

II II 

6 1 7 

4 

II 

4562 2 7 6 , ,'.',; 

'5~' 

II 11 

4 7 7 ..~ -'",... 

5' II II 

6 5 7 

7 'CIPC 2 9 2 

8 

II 

4 8 2 

9 

II 

6 7 1 

lQ Gei(Y 30028 1 9 6 

11 

II II 

2 8 7 

12 

II II 

3 8 7 

13 Stoddard Solvent 75 gal 8 7* 

14 M&B 2,4,D-B ~ 4 3 

15 

II II 

1 4 4 

16 Check 8 1 

*Barnyard grass controlled. Also early germinating red-root and purslane. 

" However at time of rating new weeds Here present and treatment barely considered 

commercially acceptable. 

SUMMARY 

From the above tests it appears that for pre-emergence or at pl8.nt'ing 

application, Chloro IPC, Vegadex, EPTAM,and the netr ACP460 Dinoben, show excellent 

promise. The ·[:riazine. derivative 30028 is not safe on mineralsoUs· but 

seems to be an added possibility for carrots~ro'l"in on muck. Forpost-emergence 

application Niagara No. 4512 and No. 4562 appear to be serious competitors for 

the place now held by Stoddard Solvent. However, where barnyard grass is a 

problem these new chemicals are not as effective as Stoddard Solvent. 

l·.

CHBHICALWElDINGc:. SIT All) SlBDID ONIOIS Ql.CInf IN JaNlaAL SOILS 1• 

C11A1L18J. 

JQJ. 2 • 

ttach of the chemic.1 n.d CODUol.1 U •• Uou Df GIlio... baa be.n cJoaeon 

IlIUck10US. '1'be 1nfomatiOD obtai_ OIl c cb SOUl CaD not alW"S be applied 

to crops grOlfD in lI1ael'al aoU.. AltllouP the acI' .... of ooio ... grOlfD in llilleral 

soUs ia limit.d. 'noush h p'0lfD to "anut chtllllical weed iav.stisaUool. 

'lbil iDY.sUs.Uon :Lac1uclea a ccab1utioo of both pr .......... nc. and postemerpac. 

application of herbicide. OIl 0Di0D8 p'0lfD frOID s.ta and frOIDs.eda. 

DQfIPM 

S.ts of the onion v.. ietyn. ........ pl.nteel Nay 12.1958. Pre-emeraence 

appl1c.t101lS of herbicidea, Cb1ol'O IPC .114 Randox were macle Nay 14. An emersenee 

applic.tion of ltOCNwas made Nay 2OtIl. PoaC... r .... ce applic.Uool nn ..cte 

Nay 27 when the 01l10D1were 6 lIac", t.U. Iadiv1clual p10te were 20 feet long by 

2 feet wid.. Tre.tments were r_1II1.eeI in eacb of 10 b10cka. 

In the secoDcl experiment seecls of the variety tel10w Sweet Spanish were 

planted Hay 12, 1958. Pre.emerPIICe applic.tions of

105. 

The results of onions grown from seed is presented in table 2. Weedcontrol 

was significantly increased by all chemical treatments as compared to the 

untreated check. In the pre-emergence treatments weed control was best where 

Randox was used as compared to the other two chemicals. Post-emergence treatment 

has little effect on weed control. 

Onion stand was significantly better as compared to the untreated check 

plots where KOCNwas used in the pre-emergence application and followed in the 

post-emergence applications by Chloro IPC at 3. 6 and 9 Ibs. and by Chlorazin 

at 6 Ibs. per acre and where Chloro IPC was used in the pre-emergence application 

and followed by the post-emergence application of Chloro IPC at 9 Ibs. and 

Randox at 8 lbs. per acre. 

Weight of bulbs at harvest were significantly increased as compared to the 

untreated check plot with all pre-emergence treatments of Chloro IPC. emergence 

treatments of KOCNand one of the eight Randox treatments. 

CONCLUSION 

Randox in a pre-emergence treatment at the chemical rates used gave better 

weed control than either Chloro IPC in a pre-emergence treatment or KOCNapplied 

at time of onion emergence. Post-emergence treatment had little effect on weed 

control. With set 6nions yields were good with all three pre-emergence chemical 

treatments. With onion grown from seed Chloro IPC in a pre-emergence treatment 

and KOCNapplied at time of onion emergence were the best treatments.

'.), 

106. 

Table I. Weedcontrol, plant stand and weight of 'bulbs under chemical herbicide 

treatment of onions ·grown from sets. 

Emergence & Pre-Emerg. Post-Emergence Average per plot at Harvest 

Rate per Rate per *Weed Onion Weight 

'Herbicide Acre Herbicide Acre 'Control Stand Bulbs 

lbe. Ibs. lbs. 

Nothing NothiDg -- 10.0 23.4 4.5 

KOCN 12 KOCN 18 4.3 

, .. ,..,' 

32.6 7.5 

" " ChIaro IPC 6 4.3 29.1' 6.3 

" " Randox 8 2.6 30.8 7.2 

" " CbloraziD 3 3.4 29.1 6.8 

Chloro IPC 6 KOCN 18 2.6 37.5 . a.7 

" " " Chlaro IPC 6 3.5 33.5 8.7 

" " " Randox a 1.9 37.6 8.8 

" 

II II 

Chlorazin 3 2.2 36.4 8.4 

Randox 8 KOCN 18 1.8 34.4 7.5 

" " Chloro IPC 6 1.3 30.3 6.8 

II 

" 

" Randox 8 1.1 34.4 8.0 

II 

Chiorazin 3 1.0 36.3 8.9 

Least Significant Difference (P: .05) 

II " II (P::I .01) 

6.9 

9.1 

*WeedControl 1-10 

1 Perfect WeedControl 

10 NoWeedControl

107. 

Table 2. Weedcontrol. plant stand and weight of bulbs under chemical treatment 

of onions grown from seed. 

Emergence &Pre-Emerg. Post-Emergence Average per Plot at Harvest 

Rate per Rate per *Weed Onion Weight 

Herbicide Acre Herbic.!2!. Acre Control ~ of Bulbs 

lbs. Ibs. lbs. 

Nothing Nothing 9.4 37.0 5.2 

KOCN 12 KooN 18 3.3 51.1 11.7 

" Chloro IPC 3 4.7 63.0 13.9 

II II II 

" 

6 4.2 65.4 17.5 

II II 

" " 9 3.9 60.7 14.4 

II II 

Randox 8 4.4 49.6 12.3 

II Ch1orazin 3 4.6 51.8 12.7 

" " " 6 4.3 60.2 13.2 

Ch1oro IPC 6 KOCN 18 3.0 49.4 13.4 

II II 

Ch1oro IPC 3 5.3 46.5 10.9 

II 

6 4.8 41.5 11.9 

" " II II 

" " 9 3.5 60.9 15.5 

II 

" RS::ldox 8 4.1 60.5 15.5 

II 

" 

Ch10razin 3 3.3 51.5 13.9 

II II II 

6 4.7 43.0 12.1 

Randox 8 KOCN 18 1.5 33.7 8.1 

II II 

Ch1oro IPC 3 1.3 32.3 9.3 

II 

II 

" " 6 1.2 33.5 11.6 

II II 

" 

" 9 1.2 26.1 9.2 

II II Randox 8 2.1 31.4 9.1 

II 

" Cb10razin 3 1.7 22.4 5.8 

II 

" " 6 1.8 30.0 .7.8 

Least Significant Difference (I': .05) 1.4 16.2 4.6 

II 

" " 

(P: .01) 1.9 21.3 6.1 



10 Full WeedGrowth 

.'

ASSistant Professor of Olericulture, Department of Horticulture, College of 

Agriculture and EXDer1ment Station. TIl", P..nnAv1vAnfA !':~A~" '''''f ...... a4~.. 

D8. 

WEEDINGOF BEETSWITHCHEMICALHERBICIDES 1• 

About 10.00 acres of beets are grown in Pennsy~vania each year. Weeding has 

been a major production problem. The chemical most used for weeding has been 

salt applied at an acre rate of 400 lbs, in 200 gallons of water at the time 

beets have 4-5 true leaves. This treatment may not be satisfactory if the weeds 

are large at time of tr.eatment or if the major weed is purslane. Satisfactory 

control of weeds with geiad beet growth has been obtained in past years using 

other chemicals in a pre-emergence application. This is a continuation of that 

investigation. 

PROCEDURE 

Seeds of the beet variety Seneca Detroit were planted May 15, 1958. Pre~ 

emergence applications of herbicides were made May 19. Salt was applied July 2 

when the beets had 4-5 true leaves. Individual plots were 23 feet long and 2 

feet wide. Treatments were randomized in each of 10 blocks, 

The chemica1l1 were applied with a small sprayer over the vegetable row for a 

width of 12 inches. The growing season was favorable with rain well distributed 

and averaging about 1/2 inch a month in excess of normal. An estimate of weed; 

control was made prior to harvest on a basis of 1 to 10, 1 being most desir~le 

and 10 being least desirable. Beets ~e.barvested August 5, 1958, 

gSVLTS 

The results are presented in table I. All chemicals significantly increased 

weed control as compared to the untreated check. The number of marketable roots 

was significantly increased over the untreated check with the Endotha1, TCA 

combination, Endotha1 alone, Randox at 6 and 9 1bs. per acre and Monuron. The 

best weight of marketable roots was with 9 1bs. of Endothal + 10 lbs. TCA, 12 lbs. 

of Endothal + 10 1bs. TCA, 9 1bs. of Endotha1, 12 lbs. of Endothal, 9 1bs. of 

Randox, 1/2 lb. of Monuron and 3/4 1b, of Monuron. 

CONCLUSION 

Taking into consideration weed control, number and weight of marketable 

beets the best treatments were Endotha1 alone at 9 and 12 1bs., Endotha1 in 

combination witb TCAat 10 1bs., Manuron at 1/2 and 3/4 1bs. and Randox at 

9 lbs, per acre. 

Authorized for publication on Nov. 19, 1958 as paper No. 2317 in the Journal 

Series of the Pennsylvania Agricultural Experiment Station.

109 

Table I. Weedcontrol, number and weight of marketable beets under chemical 

herbicide treatments. 

AVERAGE PERPLOT 

Rate per When ~eed No. Mkt. Wt. Mkt. 

Herbicide Acre ~pl1ed Control Roots Roots 

1bs. 

lbs. 

Nothing 9.5 52.0 5.3 

Salt (NAC1) 400 1bs. Post-emerg. 6.7 68.4 8.9 

Endothal & TCA 6 + 10 Pre-emerg. 5.1 71.5 9.1 

" " 9 + 10 " 3.5 84.1 11.7 

" " 

12 + 10 " 3.4 79.4 11.2 

Endothal 6 " 5.3 71.4 9.5 

" 9 " 4.9 80.9 10.5 

" 

12 " 

3.6 100.6 12.6 

FW450 10 " 4.9 51.4 8.0 

Randox 6 " 3.2 77.1 9.3 

" 9 " 2.1 74.4 10.6 

" 12 

" 1.5 51.9 8.5 

Monuron 1/2 " 4.0 76.4 10.7 

II 

3/4 " 2.9 81.6 10.6 

Chloro 1PC 3 " 4.9 53.0 6.1 

Vegadex 4 " 5.9 61.2 7.3 

" 

6 " 4.8 63.5 9.1 

" 8 

" 

3.3 60.4 10.1 

EPTAM 4 " 6.7 54.4 6.4 

" 6 " 6.2 55.4 6.6 

Least Significant Difference (P: .05) 1.5 19.4 2.2 

" 

II 

" 

(P: .01) 1.9 25.6 2.9 


1 Perfect Weed Control 

10 Full WeedGrowth

110. 

ANEVALUATIONOF PRE-EMERGENCE HERBICIDESIN FIELD CORN 

ANDTHEREACTIONOF SEVERALINBREDSTO THESEHERBICIDES 

William F. Meggitt and John C. Anderson l 

There has been a continuing search for a pre-emergence 

herbicide that will control both broadleaf and grass weeds in 

corn. Various formulations of 2,4-0 have been evaluated and 

used for this purpose for several years. The results and degree 

of weed control have generally been satisfactory. However, 

there are all too many cases where due to environmental 

conditions at or following the time of application, the 

2,4-D materials have failed to control weeds or have given 

some crop injury. -,Also 2,4-D has found oQjection in the. possibility 

of injury to nearby susceptible crops • There are ... 

several new chemicals Which are being evaluated for the purpose 

of pre-emergence control of weeds in ,corn. As these new 

materials are introduced, it is necessary to evaluate them 

under varying environmental conditions. Further it is necessary 

to determine the susceptibility of corn varieties and 

strains to these materials. 

The purpose of this study was to evaluate the more promising 

herbicides either alone or in combination on one of 

the recently introduced NewJersey hybrid varieties and to 

determine the most satisfactory rate of application under 

1958 grOWing conditions' in order that they might be contrasted 

With the extremely dry conditions of 1957. A further purpose 

was to test the susceptibility of the more prominent inbred 

lines to those herbicides felt to hold extreme promise. 

PROCEDURE 

On May 28 New Jersey No. 9 field corn was planted in 

hills 42" by 42" with five seeds per hill on a Sassafras 

loam. On May 29 plots 4 hills by 11 hills (14 feet x 38.5 

feet) were treated with the follOWing pre-emergence herbicides: 

2 - chloro-4.6-bis(@thylamino )-s triazine (Simazine) 

1. 2. and 4 Ibs. per acre. 

Ethyl N. N-di-n-propylthiocarbamate (EPTC) 6 Ibs./A 

2.4-dichlorophenoxyacetamide (2.4-D amide) 1.5 and 

2 Lbs , per acre 

2.4-dichlorophenoxyacetic acid; low volatile ester 

(2.4-D LVE) 1.5 Ibs. per acre 

2 chloro-N-N-diethylacetamide (CDAA)3 and 6 lbs./A 

2.36-trichlorobenzoic acid (TBA) t lb. per acre 

used in combination with CDAAat Ii and 3 pounds 

per acre. 

lAssistant Rese ar-ch Specialist in Weed Control and 

Research Specialist in Corn B~eed~ng. De~t •. 0f.~arm.Crops.

111. 

The experimental design was a randomized block with four 

replications. All herbicides were applied in water at 

20 gallons per acre with a bicycle-type plot sprayer as 

an overall coverage. 

Stand counts were made on June 13 and the stand was 

thinned to 4 plants per hill after counting. An estimate 

of the percent control of broadleaf and grass weeds was 

made on July 2 by three evaluators independently. The 

major weed species in the experimental area were prostrate 

pigweed (Amaranthus graecizous). redroot pigweed 

(Amaranthus retrof!exus). oarnyard grass (Echinochloa 

crusgal11). crabgrass (Digitari8, SI?).foxtal1 (Setaria 

sp.). purslane (Portulaca oIeracea). and lambsquarter 

(Chenopodium ~). 

There was no cultivation throughout the growing season 

except in the handweeded check plots in which two 

hand hoeings were made. 

In the second experiment ten of the more common 

inbred lines of field corn were planted in plots 2 by 8 

hills. The ten inbred lines were Wf9. W22. J47. J48. 

J48ms (J48 male sterile). Al58. CI03. J440. 9206. and Hy2. 

The first seven inbreds were planted three seeds per hill 

and due to a limited number of seed J440. 9206. and Hy2 

were planted two seeds per hill. The experimental design 

was a split plot latin square with herbicides as whole 

plots. The herbicide al?plications were simazlne 2 lbs. 

per acre. 2.4-D amide lt lbs. per acre. and CDAAat 3 

Ibs. per acre plus TBAat , lb. per acre. All herbicides 

were applied the day after planting (May 29) in g) gallons 

of water per acre. All plots were cultivated on 

July 16. 

Stand counts were made on June 12 and estimate of 

percent weed control was made on July 2. Counts of the 

number of plants surviving at harvest and the number of 

"off-type" plants were made on October 1. The corn was 

harvested on October 2. 


The results of the first experiment are shown in 

table 1. Under the conditions of high moisture in 1958. 

simazine at 2 and 4 pounds provided the most complete 

control of broadleaf and grass weeds. For control of 

broadleaf weeds 2.4-Damide and low volatile ester were 

as effective as simazlne but gave slightly poorer grass 

control at It pounds although grass control from these 

materials was adequate. EPTCgave nearly complete control

112. 

Table 1. The effect of pre-emergence herbicides on weed 

control and yield of field corn. NewBrunswick, 

New Jersey.' 1958. 

Rate Percent Corn 

Herbicide Lb./A \veed Control Yield 

.Broad- - BU./A 

" 

leaf 

Gra~s 

Simazine 1 98 " (55 104.3 

2 100 93 1~,.3 

4 100 97 99.2 

EPTC 6 98 78 100.9 

2,4-D LVE 1.5 100 85 98.1 

Emid 1.5 100 75 101.2 

2 100 95 97.9 

CDM.(solventless) g. 5 40 9~.8 

54 88 9 .9 

CDAA(Randox) 3 5 40 86.0 

6 20 80 89.3 

CDAA-T 3 68 53 91.1 

6 88 85 98.5 

CDAA+ TBA It + t 55 60 104.1 

3 + t 78 72 99.6 

CDAA-T+ TBA 3 

'1 

88 90 102.3 

+ ~ 

Handweeded Check 107.9 

Check 78.5 

L.S..D. .05 10.1 

.01 14.6 

of broadleaf weeds and. adequate grass control. Control 

from the combination ofCDAA and TBAwas not as complete 

as in 195Tbut was adequate • CDAA-Talone or in combination 

with TBAwas more effective than CDAA. CDAAwith or 

without a solvent was not effective in control of broadleaf 

weeds whereas 6 pounds per acre provided good control 

~f grasses. CDAA-Tgave much better control of broadleaf

113. 

weeds. In the experiment on the evaluation of inbreds 

simazine gave 98 percent control of all weeds, 2,4-D 

amide 95 percent, and CDAAplus TBA95 percent. 

There were no reductions in stand of field corn 

from any of the herbicides. EPTC showed some injury 

to the growing plants. This injury occurred on some 

plants in a hill while others in the same hill were 

completely normal. The injury was manifested as stunted 

plants which were twisted and some failed to unroll 

from the spike. It was limited to less than 10 percent 

of the plants and had no effect on yield. The lower 

yields in table 1 for CDAA,CDAAsolventless, and 

CDAA-Tat 3 pounds per acre were due to the competition 

from weeds which were not controlled. The handweeded 

check yield was higher than any herbicide treatment, and 

this was probably due to some cultivation effect from 

handhoeing. Yields from plots treated with simazine, 

2,4-D amide, 2,4-D LVE,EPTC, and CDAA-TBAcombination 

were not significantly lower than the handweeded check. 

The data in table 2 on the evaluation of inbred 

lines show that simazine and the combination of CDAA-TBA 

had no apparent effect on any of the inbred lines. There 

was no reduction in stand, surviving plants, yield and 

no increase in "off-type" plants. 

The stands of A158 and 0103 were significantly reduced 

by 2,4-D amide. There appeared to be an increase 

in off-type plants for 9206 and J48ms in 2,4-D treated 

plots; however, this difference was not great enough to 

be significant. Yields for J48, Al58, and 0103 were 

significantly reduced by. 2,4-D amide when compared to 

check. The yields for plots of J48ms treated with 2,4-D 

amide were significantly lower than simazine or ODAA-TBA 

treated plots in which weed control was more complete 

than in cultivated check. 

SUNMARY 

, 1. Six herbicides alone and in combination were 

ev.aluated for weed control in field corn. 

2. Slmazine, 2,4-D amide, 2,4-D LVE, CDAAplus TBA 

and CDAA-Tprovided satisfactory control of grass and 

broadleaf weeds with no reduction in yield of corn. EPTC 

provided satisfactory control of weeds with no yield reduction 

but some injury was noted on the corn shortly after 

emergence.

Table 2. The effect of three herbioides on stand and 

yield per plot of ten m~Jor field corn inbred 

lines. NewBrunswick, NewJersey. 1958. 

Inbred Simazine CDAA+ TEA 2i4-D amide Check 

lines Stand Yield Stand Yield St~nd Yield Stand Yield 

plants Lb. Plants Lb. plants Lb. Plant,s Lb. 

Wf') 44 14.5 41 13.7 41 13.1 4:3 14.1 

W22 40 11.0 38 11.3 36 9.2 40 11.4 

J47 28 15.7 32 16.0 28 12.5 26 ,14.6 

J48 40 21.2 40 19.1 43 14.4 42 19.2 

J48ms 44 24.3 43 21.9 42 18.3 43 21.4 

Al58 

C103 

28 

28 

7.6 

11.1 

27 

33 

7.6 

13.1 

17 

,20 

4.227 

6.4 ,29 

7.4 

13.5 

J440 28 12.2 32 14.3 30 12.8 30 11.1 

9206 26 8.6 27 9.5 24 5.6 23 8.4 

Hy2 28 9.5 24 6.9 26 6.7 28 6.9 

L.S.D. for yield (Herbicides within inbreds) .05 

•01 

3.6 

5.4 

lb • 

lb. 

3. Simazine, 2,4-D amide, and CDAAplus TBAwere 

tested on ten inbred lines for weed oontro1 and effect on 

stand, development and yield of oorn. 

4. Simazine and CDAAplus TEAhad no apparent effeot 

on any of the inbred lines. Yields of J48,J48ms, A158 

and CI03 were reduoed by 2,4-D amide. None of the other inbreds 

were affected by 2,4-D amide.

THE INFLUENCEOF WEEDCOMPETITIONON GROWTHANDYIELD OF 

SPRING OATSANDCORN . 

Ming-Yu Li, William F. Meggitt and Richard J. Aldrich l 

Abstract 2 

The presence of weeds have brought tremendous losses to 

agricultural producers allover the world. For herbicides 

and cultural practices to be used most effectively in controlling 

weeds, basic information concerning these losses, 

and the period in which they occur are most urgently needed. 

This study was initiated to obtain information concerning 

the relationship between stages of crop development and injury 

by weeds, as well as to evaluate the relative importance 

of competition for essential elements. 

Experiments were conducted in 1956,l957, and 1958 at 

the New Jersey Agricultural Experiment Station and Rutgers 

The State University, New Brunswick, New Jersey. 

Weeds were allowed to grow in competition with crops for 

pre-determined intervals after emergence of crops and then 

were carefully removed by hand. In order to insure weed 

competition, lambs quarters (Chenopodium album) and pigweed 

(Amaranthus retroflexus) were broadcast rn-tne corn plots, 

and wild mustard (Brassica spp.) was seeded with the spring 

oats. 

In order to study the extent of weed control needed for 

row crops, weed-free bands of various widths were left directly 

over the row. Three different patterns of weed removal 

were also used. 

All crop and weed samples taken at the established dates 

of weed removal were retained for recording of green and dry 

weight and chemical analyses. 

In 1958 particular interest was placed upon competition 

at various fertility levels in both crops. 

115. 

lResearch Fellow; Assistant Research Specialist in Weed 

Control, Farm Crops Dept., Rutgers; and formerly Research 

Agronomist, ARS, CRD, USDA, New Jersey Agricultural Experiment 

Station, respectively. 

2To be submitted to WEEDSfor publication.

116. 

Sprin~ Oats. Data obtained from the three years showed that 

spring oats which gr~w in competition with weeds produced 

less dry matter, less grain, less tillers, less seeds per 

panicle and had a lower content of nitrogen than those growing 

free from weed competition. 

Grain yields were reduced when weed competition was longer 

than one week after emergence of oats in 1950 and 1957, and 

longer than three weeks in 1958. The unusually cool spring 

which retarded weed growth during the first two weeks of competition 

in 1958 pcobably account for the difference between 

the 1956-1957 season. Since they were not in any way contradictory 

to each other they only substantiated the finding that 

the critical stage of weed comnetition is during the early 

stage of crop growth. Weeds capable to~making rapid growth 

during early stage of crop development depress the crop yield 

to a greater extent than those which develop later in the 

season. 

In 1958 the grain yields in weedy plots receiving 600 

pounds of 5-10-10 fertilizer per acr~ were higher than those 

in weed-free plots where

Pre- and Post-Emergence Weed Control in Field Corn 

John A. Meade and Paul W. Santelmann 

y 

11 

117. 

Field corn was",planted on June 5th, and treated either pre- or 

post-emergenc~with various herbicides (alone or in mixtures). Millet, 

pigweed and lambsquarters were seeded to insure an even weed stand. Preemergence 

treatments alone or as mixtures were applied on June 10 just 

prior tQ"eme,rgenoe,'Post-emergence applications were made at one of 3 

stages: A, -,spike or very early single leaf; B-3 leaf stage when "the 

corn was 4to' 6 inches tall; or C - 5 to 6 leaf stage, corn 6 to 8 .Lnche s 

tall. A fairly heavy rain fell the evening of June 10,and also after 

the "A" post-emergence stage. 

All treatments were made with a bicycle sprayer in 30 gallons of 

water per acre. The soil type is a fairly heavy loam, the soil being 

fairly moist at time of application. Air temperatures were 80 0 F for the 

pre-emergence and' first stage post-emergence treatments. The second and 

third stage post-emergence treatments were made when the air temperature 

was 70 0 F. 

The plots were 3 rows by 20' long and in 3, replications. The center 

row was harvested for yield determinations which are reported as bushels 

per acre of #2 corn at 15.5% moisture. Weed ratings on a basis of 0 = no 

injury, 10 = complete control were made on July 25th in all plots. The 

plots were not cultivated with the exception of the cultivated checks. In 

the pre-emergence mixtures experiment there was also an uncultivated check 

and a hoe-scraped check, in which the soil surface was disturbed as little 

as possible. 

Temperatures during the growing season were moderate and adequate 

moisture was present all season. By Maryland standards this was a cool, 

wet year. Weed growth was very good and corn yields were high. 

Significance between means was determined by the use of Duncan's 

mul t LpLev-r ange test. 

Results 


The weed ratings and yield of the pre-emergence test are reported 

in Table 1. None of the treatments caused a significant reduction in 

yield below the cultivated check. One treatment, EPTC at 6 pounds per 

acre, had a significantly higher yield than the check. The lack of 

significance between the treated plots and cultivated check indicates that 

controlling weeds with chemicals was, in this test, as satisfactory as 

Mechanical cultivation. 

.!.I Miscellaneous Publications No. 340 ,Contribution No. 2976 

of the Maryland Agricultural Experiment Station, Department of 

Agronomy. 

Assistant Professors, Department of Agronomy, Maryland Agricultural 

Bxperiment Station, College Park, Maryland

118. 

Table 2 lists the weed ratings and yield of corn in the pre-emergenc~ 

test where mixtures were used. The yield of the scraped check was --/ 

significantly higher than the rest of the plots. None of the chemical 

treatments produced yields higher than the cultivated check. There were 

several treatments which had significantly lower yields than the cultivated 

check. Some of this is undoubtedly due to increased weed competition 

as indicated by the weed ratings. There were no significant 

differences between yields of the 2,4-D+ Randox treatments and the individual 

components, but the weed control of 2,4-D +Randox, Ii + 2 lbs 

per acre is better than either one separately. 

In Table 3 are listed the results of the post-emergence trial in 

corn. Although there are no significant differences between check and 

treated plots, it would seem to appear that some of thc treatments caused 

a reduction in yield. Weed control in general w4S quite good. 

SUMMARY 

Various herbicides were used pre- and post-emergence on field corn 

in 1958. Pre-emergence, only Eptam at 6 pounds per acre was significantly 

better than the cultivated check. Yields from other plots treated with 

Simazine, Randox, diuron, ACP 569. Emid, DNBP, 3Y9 and 2,4-D were not 

significantly different from the cultivated check. 

In another pre-emergence experiment in which various herbicides 

were used alone and in mixtures, plots scraped with a hoe to remove weed 

growth yielded significantly better than all other treatments. Plots 

which were neither sprayed nor cultivated yielded significantly less than 

all other treatments. Corn treated with 2,4-D or Randox alone was found 

not to be significantly different in yield from that treated with mixtures 

of the two ll*llbicides. Plots treated with mixtures of dalapon and DNBP 

or dalapon and 2,4-D yielded better than those treated with dalapon alone. 

Dalapon alone did not control broadleaved weeds satisfactorily, but the 

mixtures did. Some corn injury may have resulted from the use of dalapon. 

When used post-emergence, 2,4-D, Emid, Simazine, DNBP, DNBP+dalapon, 

3Y9 and ACP 569 satisfactorily controlled broadleaved weeds. Dalapon 

alone and amitrol did not. Only Simazine, dalapon and ACP 569 satisfactorily 

controlled grass weeds. With regard to yield, no treatment was 

significantly better than the cultivated check.

( 

Table 1 Weed Control Ratings on 7/25/58 and yield of Corn From Plots Treated Pre-emergence with various 

herbicides, 1958. Ratings on a basis of 0 = no control, 10 • complete control. Average of 3 replications. 

7/25/58 

Weed Rating 

Yield 

Rate Broad- Bushels 3ignificance Test 

(.J.bsJA.-L J.eave9 GOWL 

Rate Yield. 

.~ -T~-eatment 

Eptam 6 Iho I 

'Tr.AAt:mpnt -- 

Simazine 1 9 10 121 Simazine 3 136 I 

2 10 10 108 Randox h 135 

1 . 

3 10 10 136 Diuron 3/h 132 ! I 

Randox h 7 3 136 Diuron I} 

6 8 5 120 ACP-569 2 

131 'I' 

1281 I I 

Randox'1' h 8 10 .. 118 RandQx 6 

,,'II II1 

6 10 10 126 S. Randox 2 123 i I' 

Eptam 2 h h 116 Emid 2 123 ' 

h 7 3 110 Simazine 1 121 III, 

6 10 9 lho Randox 6 120 II I 

DNBP .3 3 8 117 Randox T h 118 II I 

h 2 7 10h mmp 3 III . 

2,h-D LVE 1 3 8 110 Eptam 2 

116 I 

I} 6 8 106 ACP-569 h 

115 I . 

£MID 2 8 8 123 S. Randox h 113 i 

Diuron 3/h 9 9 131 CuI t , Check - 112 I; 

11 10 10 132 3Y9 2 III 

3Y9 2 8.;.. 8 III 2,h-D 1 110 

h 8 10 110 Eptam h 110 

ACP-56S 2 7 2 128 3Y9 h 110 

h 9 5 115 Simazine 2 108 

,II!I 

Solventl~ss 2 3 1 123 2,h-D 1~ 106 ' I 

Rendo. h 7 6 113 DNBP h 10h I , 

Check 

- 112 

f.J 

~y 

* 

two means not connected by the same line are significantly different at the .05 level. 

f-' 

Lny two means connected by the same line are not significantly different. -0.

) ) 

Table 2 ./eed Control Ratings and Yields of Corn Treated Pre-emergence with various herbicides and mixtures 

herbicides Control given as 0 0 no control, 10 c complete ~ontrol, 1958. Average of ~ replications 

7/2/58 7/25/58 

'/eed Hatings .Yeed Ratings Yield Significance Test 

Treatment Hate Broad- Broad- Bushels 

(lbs/A) leay«W G.E!.s~ !ellved ~~~ Per, ACE~ --_._-- 

Treatment Rate _Y!.-e..1.:d* 

DNBP l~ 6 b. 0 0 54 

Scraped Check 109 

'3 6 6 0 1 67 Cult. Check 87 

Randox 2 3 3 z 3 81 

2,4-D l~ 87, 1 

4 8 9 '5 5 71 Randox 2 8li 

Dalapon 1 2 7 2 0 47 

DN + Dalapon 3 + 1 81 :' 

2 3 8 0 0 42 

Randox + 2,4-D 2 + 1~ 

2,4-D LVE l' 781'1 

9 8 4 5 87 

"- 

4-:-l~ 771! 

DN .~ Dalapon ~+1 4 3 0 0 50 

Dalapon+2,4-D 1+l! 74 

3+1 8 8 I 1 81 

Z+l} 1" 

3+2 10 8 1 6 65 

Randox 4 

2,4-D+Randox 1!+2 9 10 7 8 78 DN!!!' 3 671ill, 

1!+4 10 10 8 8 77 DN+dal 3~2 65' Ii 

2,4-D+Dalapon 1; +1 7 9 4 b. 74 

1 t+2 62 I 

1~+2 10 10 '7 7 73 DN l~ 54 I 

Cult. Check 87 

DN+dal ,I 

1~+1 50 

'Jncul t , Check 20 

i 

Dalapon 1 47 

3craped Check 109 

2 42 

Uncult. Check 20 

~~Ii!: 

* Any two means not connected by the same line are significantly different at the .05 level • 

•\ny two meanS connected by the same line are not significantly differen~ • 

o 

(\/. 

H

( 

( 

Table 3 - Weed Control Ratings and Yield of Corn from Plots treated post-emergence with various herbicides 

at varying stages of growth. Stage A ~ spike; B ~ 3 leaf; and C - 6 leaf. Ratings as 0 = no control, 

10 = complete control. 3 replications. 

r!:.eatments 

z,4-D 

;;mid 

Hmazine 

)NBP 

)alapon 

)NBP 

lalapon 

IV9 

~P-569 

ni -trol 

aeeck 

amine 

Rate 

(lbs/A) 

1 

1 

1,. 

6~ 

l~ .~ 

~. 

Ii 

3 

1 

1 

Itt-I 

3+1. 

1~+1 

3+1 

2 

4. 

~ 

3/ l:· 

1 . 

i 

3/4 

3/ 4 

stage 

---' - 

C 

c 

C 

~ 

C: 

A 

A' 

B 

B 

A 

B 

A 

k· 

B 

.,13:' 

C 

C 

B 

B 

C: 

C 

B 

7/25/58 

Weed Ratings 

Broad;" 

iel!lved Grass 

10 

10 

10 

9, 

8, 

5 

6, 

7 

10· 

o 

1 

5 

9 

:t6 

104 

8 

9 

6 

9. 

8" 

4 

2 101 

1 100 

4 99 

8 

129 

:9< 111 

,2 

96 

'4 86 

1 95 

8 107 

9 

82 

ro 79 

8 100 

9 118 

6 96 

8 115 

1 100 

5 105 

9 103 

9 96 

6 117 

9 100 

9 116 

112 

Yield' 

Significant Test 

Busbe1s 

Per Acre Treatment Rate 3tag.~. Yie1d* 

Simazine 

DN+Dal, 

ACP 569 

ATA 

DN+dal 

Cui t .Cleck - 

6: 

Simazine. 

DNBP 

3Y9 

ACP-569 

2,4-P 

3Y9 

Emid 

DN+dal 

ACJ>-569 

Emid' 

ACP-569 

DN+dal 

, DNBF 

DNBP 

DNBF 

Dalapon 

Da1apen 

:3 

3+1 

! 

3/4 

3+1 

3 

4! 

1 

Z 

i 

It+ l 

3/~ 

1 

3/4 

l!+l 

It 

12 

3 

1 

1 

C 

A 

C 

B 

B 

C 

B 

C 

o 

C 

C 

c 

A 

C 

C 

B 

B 

A 

B 

A 

A 

8 

129 

1'18 1 

117" 

116 ~,' 

.1151: 

112.!1 

'111 

109 :'. 

105 . 

, 104 : 

101 ;; 

100:, 

100 !' 

100 i 

100 J' 

99 i' 

96 1' : 

96 , 

961 

95 1; 

86 

86 

79 

~J 

* Any two means not connected by the same line are significantly different at the .05 leve1~ ~ 

two means connected by the same line are not Significantly different. 

I-' 

-o 

>-'

122. 

PRE-ENERGENCE WEEDCONTROLIN CORNY 

Henry w. IndyIJ! 

The value of 2,4-D in combating the weed problem in corn is well 

recognized. Its herbicidal activity, however, has limitations which does 

not permit its effective use in every weed situation or under differing 

environmental conditions. The annual grassy weeds for ~the most part have 

been resistant to 2,4-D. The residual effect or period of effectiveness is 

not as long as would be desired in many cases. Serious injury to corn has 

often resulted from its use as a pre-emergence treatment on sandy soils. 

An urgent need exists for an economic and reliable pre-emergence herbicide 

which can satisfactorily overoome these limitations of 2,4-D. 

A sununary of two years I results (1957-1958) on the performance of a 

number 0 f di fferent herbicides evaluated as pre-emergence treatments on corn 

grown on light textured soil in Delaware is presented in this paper. 

Procedure 

The herbicides and their respective rates of application indicated in 

Tables 1 and 2 were evaluated as pre-emergence treatments on corn at Georgetown, 

Delaware. The soil in the experimental area was a Norfolk loamy sand. 

Individual plots consisted of 4 rows, each 15 feet long and spaced 3 feet 

apart. Conn 870 hybrid corn was planted at a depth of 1,5 inches and at a 

population 0 t' approximately 14,000 plants per acre. One day a t'ter planting 

corn, all chemical treatments with the exception of Randox (granular) and 

ACP-M-518-I were applied with a modified bicycle-type experimental plot 

sprayer at a pressure of 30 psi. The low concentration of each herbicide 

was applied in solution at the rate of 20 gal./A. and the double concentration 

at 40 gal./A. The double concentration was applied by spraying the designated 

plots twice using the single rate calibration on the sprayer. Randox (granular) 

and ACP-M-5lB-I were applied with a lawn spreader as dry materials. 

Broadleaf weeds which predominated included pigweed (Amaranthus retronexus), 

ragweed (Ambrosia artemisiifolia), and lamb's quarters (Chenopodium 

album). Crabgrass (Digitaria sanguinalis) was the predominant grass with a 

relatively light but well distributed infestation of nutgrass (C:yperus 

esculentus). 

Weed control ratings and corn population count were taken 5 weeks after 

the application of chemical. During the remainder of the season all plots 

received one cultivation. The plots were harvested in the fall for yield data. 

Y Hiscellaneous Paper No. 322. Delaware Agricultural Experiment Station. 

y Assistant Professor in Agronomy, Univers;ity of Delaware, Newark, Delaware.

Nutgrass is rapidly becoming a serious weed problem in corn fields throughout 

Delaware. In these tests two materials showed encouraging results with 

respect to control of this grass. Simazin at 4 lbs./A. in 1957 and at 2 lbs. in 

........ 0 .ftA....._..L.~ .J ..1...__ .... -1... 'I"L_..L. L , .. , __ J... _ .. __ 

123. 

Results 


In 1957, sOil moisture at the~ time of plant:l,ngwas adequate for the 

germination of corn and weeds. ApproXimately two weeksarter planting, soil 

moisture became deficient and marked tne beginning of a prolonged drought period. 

The corn, crop was· a complete failure and as a consequence no yield data were 

obtained. In contrast, soil moisture in the 1958 se.asonwas very satisfaotory 

throughout the ent~re season. . 

The perform8Me. of the herbicides evaluated in 1951 are summarized in 

Table 1 and for 1958 in Table 2. These data ind;i.caW the distinct superiority 

of SiJr!azin for the control of all weed growtnas compared to the various' 

herbicides included in the tests. The most effectiv, rate for weed control 

was not consistent between the two seasons. The two pound rate during the 

moist season or 1958 gave perfect weed control whereas during the 1957 season 

poor results were obtained with this rate of appUcation •. Although satisfactory 

weed control was obtained in 19S7 with the four pound rate, it was not as 

ef't'ective as tne two pound rate in 1958. In 1958 the two pound rate was 

equally as effective as the four pound rate. 

It was interesting to note the persistance of Simazin throughout the 

season. Very satisfactory weed control was obtained throughout the entLre 

growing season even at 2 pounds per acre. Barley and ryegrass were seeded in 

tne fall as cover crops. Slight injury to these crops, particularly barley, 

was evident at the two pound rate and ratner serious injury at tne four pound 

rate. Furtner observation of these plots will be made in the spting. Information 

is needed on its residual effect of Simazin and its persistance in different 

solls under various environmental conditions. 

Slight stunting of the corn was noted during the early growth stages. 

Also, tasseling and silking of the corn on the Simazin treated plots were 

approximately three days later than the check plot. However, the yield data 

indicate no significant reduction in yield at either the low or high rate of 

application. 

Less effective but satisfactory results were obtained trom a number of 

other chemicals. In the 1957 test, NaPCPat 25 lbs./A. was the only additional 

chemical which gave good control of weeds. In 1958, Emid at 2 lbs.I'A. and 

Premerge at 6 lbs./A. were very satisfactory in controlling both broadleaves 

and grasses. Eptem at 6 lbs./A. gave very good control of grasses and fair i 

control of broadleaves. Very satisfactory control of grasses was obtained tram 

Randox at 8 lbs./A. but the control of broadleaves was very poor. A new 

material Randox-T at 6 lbs./A. not only was comparable to Randox in controlling 

grasses but was much more effective on the broadleaves. The benzoic materials, 

although very effective in controlling weeds, caused a serious reduction in 

stand and yield of corn. Benzac 1281 at 2 lbs./A. gave excellent control of 

both broadleaves and grasses. ACP-M-5l8-I was effective in controlling only 

the broadleaves.

124. 

Summa£l 

Various herbicides were evaluated for pre-emergence weed control in corn 

grown on a Norfolk loamy sand soil in Delaware during 19$1 and 1958. 

Simazin was outstanding in the control of both broadleaves and grasses 

throughout the entire growing· season. Soil moisture conditions infiuenced the 

effective rate of application, A rate of 2 lbs./A. in a moist season was 

more effective than 4 lbs./A. in a'season of less favorable moisture conditions. 

Information is needed on its relatively long residual effect. 

Satisfactory results were ob,ta1ned with NaPCPat 25 lbs./A., Emid at 

2 lbs./A., Eptam at 6 lbs./A., Premerge at 6 lbS./Aa, and Randox-Tat 6'lbs./A. 

Randox at 8 lbs./A. was errecti~ on grasses but not on broadleaves. 

The benzoic materials, BenZac 1281 and ACP-M-$18-I, were unsatisfactory 

from the standpoint of seriously reducing both corn stand and yield. 

Simazin and Eptam appear to be promising for the control of nutgrass. 

Acknowledgements 

The cooperation ot' the '('ollowing companies in providing the chemicals 

necessary for these trials is gratef'ully acknowledged I 

!mchem Products, Inc., DowChemical Co., Geigy Chemical Corp., Monsanto 

Chemical Co., and Stauffer Chemical Co.

125. 

Table 1. The effect of pre-emergence herbicides on weed control, corn 

stand and corn yield at Georgetotm, Delat·tare- 1957 

Corn 

Treatment Rate WeedControl Rating!! Stand 

Lbs./A. 13roaa:Leaves Grasses Reduction 

% 

Randox 4 2.0 5.3 4.9 

Randox 8 4.0 7.0 14.7 

Vegadex 4 3.7 5.7 7.8 

Vegadex 8 7.0 7.7 12.8 

Eptam 3 3.0 4.7 1.4 

Eptam 6 6.3 7.3 0 

NaFCP 12.$ 6.3 3.7 2.9 

NaFCP 25 8.7 7.3 1.4 

Simazin 2 7.0 5.0 4.8 

Simazin 4 8.7 8.0 6.4 

CP69361:/ 3 3.3 6.3 0 

CP6936 6 6.7 8.3 4.9 

3,4-Dl'~/ 3 0 2.7 0 

3,4-DMB 6 2.0 6.0 2.9 

Chec~~ 0 0 0 

Chec 8.0 8.0 4.9 

a/ \leed control rating: 0 - no control, 10 - perfect control. 

II CP6936 - dithiocarbamate material. 

"2/ 3,4-DI-J13 - 3,4-dimethylbenzophenone. 

~_// Checlc- cultivation identical 'to chemically treated plots. 

14, Checlc- cultivation as needed, commencingat planting time.

126. 

Table 2. The effect of pre-emergence herbicides on tfeed control, corn 

stand, and corn yield at Georgetown, Delaware - 1958 

Corn Corn 

Treatment Rate vleedContro1 RatinS¥ Stand Yield 

Lbs./A. Broadleaves Grasses Reduotion Bu./A. at 

% 15.5%Moisture 

Randox 4 0 1.6 2.9 119.8 

Randox 8 2.3 9.0 5.1 134.6 

Randox (granular) 4 0 1.6 2.9 110.9 

Randox (granular) 8 0 1.3 2.9 118.1 

Randox-T 3 6.0 1.6 2.9 136.2 

Randox-T 6 1.1 9.0 5.1 150.3 

Vegadex 4 0 1.3 2.9 118.1 

Vegadex 8 2.1 8.3 0 129.8 

Eptam 3 4.3 8.0 2.9 131.2 

Eptam 6 1.0 9.3 0 154.5 

Emid 1 6.1 1.3 0 140.0 

Emid 2 8.1 8.3 5.1 139.4 

Premerge 3 1.0 6.3 2.9 131.6 

Premerge 6 8.1 8.3 2.9 147.9 

Simazin 2 10.0 10.0 2.9 141.6 

Simazin 4 10.0 10.0 2.9 137.0 

Benzac 12811/ 2 10.0 8.1 11.4 101.6 

Benzac 1281 4 10.0 10.0 25.1 59.1 

ACP-11-518-xY 8 0 2.9 115.1 

ACP-l'~518-I 9.1 2.0 11.4 103.1 

CheC~~ 0 0 0 108.5 

Cheo 1.1 8.0 0 142.0 

LSD .0$ 9.8 

.01 13.2 

!I. l>/"eedcontrol rating: 0 - no control, 10 - perfect control. 

1/ Benzac 1281 - 2,3,6-trichlorobenzoic acid. 

y. ACP-Ivr-518-1- Polychlorobenzoic acid (on attac1ay) 

¥t Check- cultivation identical to chemically treated plots. 

~ Check- cultivation as needed, commencingat planting time.

127. 

rmns OF SILAGECOHNAS RELAT1DTO THl.USEOF S1VERALHERBICIDES 

Robert A. Peters and TJ.JarrenG. Wells* 

INTRODUCTION 

.,\ 

'Ieed control in corn has de:f'izii'tely proven to be economically worth~ile; 

thUS, screening for better herbicide treatments is a continuing process. The 

advent cif simazine and related compounds have further stimulated interest in 

weed control in corn. 

PROCEDURE 

The experiment was conducted at the Storrs (conn.) Agricultural Experiment 

Station, Storrs, Connecticut on part of a field planted to silage corn on June 

6, 1mizedblock design replica.ted 

three:timEl8~ Each plot measured 12 by 20 feet in size. Three rows of com 

in ea~h plot were sprayed with one .. IOOW ~eft unsprayed as a buffer row. Applic4tions 

of chemicals were made at -tW

) ) 

Chemicals. Used in Pre-emergence and lpergence Weed Control 

Treatment NumbtiJr 

Pre-emer/!;encEl Emer/!;epcl'! CQJ!lDlonName Rate l ~ Chemical Name 

1 2,4-DA 3/4 Dow 2,4-dichloroJilenoxyacetic acid, alkanolamine salt 

1 2 2,4-DA I! Dow 2,4-dichloroJilenoxyacetic acid, alkanolamine salt 

? 2,4-DA 3 Dow 2,4-dichloroJilenoxyacetic acid, alkanolamine salt 

3 2,4-DE (LV) 3/4 Thanpson 2,4-dichloroJilenoxyacetic acid, isopropyl ester 

3 4 2,4-DE (LV) I! Thompson 2,4-dichloroIhenoxyacetic acid, isopropyl ester 

4 2,4-00 (LV) 3 Thompson 2,4-dichloroIhenoxyacetic acid, isopropyl ester 

5 COM 3 Mansanto alJha chloro-N, N diallylacetamide 

6 CDAA 6 Mansanto alpha chloro-N, N diallylacetamide 

7 Neburon 2 Dupont 1,N-butyl-3-3,4-dichloroJilenyl-l-methyl urea 

8 Neburon 4 Dupont 1,N-butyl-3-3,4-dichloroJilenyl-l-methyl urea 

9 5 Diuron 1 Dupont 3-(3,4-dichloroIhenyl)-1,-dimethyl urea 

10 6 Diuron 2 Dupos.t'. 3-(3,4-dichloroIhenyl)-1,-dimethyl urea 

11 Simazine ,1 Geigy 2-chlor0-4,6-bis(ethylamino)-s-triazine 

12 17 Simazine 2 Geigy 2-ehloro-4, 6-bi s( ethylamino ~ -s-triazine 

13 16 S1.mazine 3 Geigy 2-chloro-4,6-bis( ethylamino -s-triazine 

14 19 TCB I! Dupont 2,3,6 trichlorobenzoic acid 

15 20 TCB 3 Dupont 2,3,6 trichlorobenzoic acid 

9 ACPM569 ~ Amchem Not knom 

10 ACPM569 3/4 Amchem Not known 

7 ATA ! Amchem Amino triazole 

8 ATA 1 Amchem Amino triazole 

13 DNBP 3 Dew Dinitro-o-sec-butylphenol, alkanolamine salt 

14 DNBP 6 Dow Dini tro-o-sec-butylphenol, alkanolamine salt 

11 Dalapon 1 Dow Dichloropropionic acid, sodium salt 

12 Dalapon 2 Dow Dichloropropionic acid, sodium salt 

15 G3003l 2 Geigy Unknown 

16 G3003l 4 Geigy Unknown 

16 Eptam 4 Stauffer Ethyl-di-n-propylthiocarbamate 

17 Eptam 8 Stauffer Ethyl-di-n-propylthiocarbamate 

~ 1 All ra\es are given in pounds of active ingredifl:lts or acid equivalent per aer-e • 

.-f

129. 

.'-..- 

TJ.BLt.1, 

Density Ratings of Weeds50 Days Following Pre-emergenee App1i,e&t1..tlns 

~f Several Herbicides.* 

Treatment Must. RagweedP);ittSl Tt!l-atm ~ RagweedFoxtail 

1. 2,4-DA 1~ 0.7 3.0 '4.7 11. Simazine 1 4.7 6.0 2.7 

2. 2,4-DA 3 1,0 2.0 2.7 12. Simuine 2 1.3 2.0 1.0 

3. 2,4-DE li 3.0 2.8 3.7 13. Simazine 4 1.0 0.0 0.3 

4. 2,4-DE 3 1.3 2.3 3.0 14. TCB li 6.7 0.7 1.7 

5. CDAA 3 7.7 6.7 4•.3 15. TCB .3 4.7 0.3 0.7 

6. CDAA 6 7.0 6.0 .3.0 16. Eptam 4 9.0 6.3 6.3 

7. Neburon 2 6.7 5.0 1.0 17. Eptam S 8.7 6.7 3•.3 

8. Neburon 4 1.7 6.0 2.7 18. Hand-weeded 0.0 0.0 0.0 

9. Diuron 1 4.7 4.3 4.0 check 

10. Diur"n 2 2.7 3.7 2.7 19. Check-not 10 7.3 2.3 

weeded 

* 0 - No stand; 10 - Complete cover 

~ergence: 

The treatment effects following application of chemicals at late-emergence 

are given in Table 2. 

TABLE2. 

Density Rating of \'leeds 43 Days Following EmergenceApplications 

of Several Herbicides.* 

Treatment Must. RagweedFgxtail Treatment Must. RagweedFoxtail 

1. 2;4-DA 3/4 1.6 3.3 3.0 11. Dalapon 1 0.7 1.0 1.3 

2. 2,4-DA 0.3 2.0 6.7 +INBP .3 

3. 2,4-DE ~'4 1.0 3.7 8.0 12. Dalapon 2 ' 0.0 2.0 2.3 

4. 2,4-DE li 1.0 1.0 3.0 + DNBP .3 

5. Diuron 1 1.0 4.0 2.3 13. DNBP 3 0.3 2.0 5•.3 

6. Diuron 2 2.3 2.7 0.7 14. DNBP 6 0.0 0.0 2.0 

7. ATA i 10.0 3.3 2.3 15. G30031 2 0.7 6.0 2.3 

8. ATA 1 3.0 2.0 5.0 16. G30031 4 0.7 6.7 1.7 

9. ACPM569, 2.0 4.3 7.0 17. Simazine 2 2.7 2.0 1.0 

10. ACPM569 1 6.u 6.3 3.7 18. Simazine 4 1.3 1,0 1.3 

19. TCB li 7:3 0.7 3.7 

20. TCB .3 6.0 0.3 0.7 

* 0 - No stand; 10 - Complete cover.

130. 

Following pre-eIlIergence treatlllentsmustard was controlled by all 2,4-D 

treatments, by the 2 and 4 rate of simazine, the 2 pound rate of diu ron and the 

4 pound rate of neburon , The TBAtreatments caused marl

Treatment Effects 

~ Corn Yields 

131. 

The effects of chemical treatment on the corn are given in Tables 3 and 4, 

giving the heights and yields respectively. Yields are showngraphically in 

Figures 1 and 2. The heights are given as a ratio of the average height of 

treated corn in each plot with that of the untreated row included in each plot. 

The yield data were based on drY matter determinations of 15 plants from the 

center row of each treated plot. 

Pre-emergence treatments: 

Significant increases in yield over the non-weeded check were ohtained from 

the high rate of either 2,4-D formulation, both rates of diuron, the high rate of 

neburon, all rates of simazine and the hand-weeded check. Twotreatments gave 

yields which were actually greater than the weeded check, namely the simazine 4 

and 2,4-DE at 3 pourds per acre. This increase can be explained by the delay 

and incompleteness of the hand weeding in the check plot. 1llhencomparing rates 

within chemicals significant increases with increasing rates were found with 

2,4-DE, and with simazine when going from 1 to 4. 

Emergence treatments: 

2,4-DA at 3/4 poums per acre was used as a standard reference treatment in 

comparing treatments. Treatments giving a significant increase in yields included 

both rates of DNBP,simazine and DNBPplus dalapon and the low rate of 

diuron' and G30031. While not significant, TCB3 and ATA! gave distinctly lower 

yields. 

Significant yields over the best 2,4-D treatments (2,4-DE) were obtained 

from the high rate of DNBPor the DNBPplus dalapon combination, 

Hhen compardng rates within chemical, as shown in Figure 2, significant increases 

are obtained by doubling the rate of ATAor DNBP.In contrast, increasing 

the rate'of TCB, diuron or G3003l caused a reduction in yield. As discussed 

under Stands, this was traced to direct injury to the corn. 

SUIIlIllary 

Since mustard was the predominant weed, the control of mustard obtained 

largely'determined the corn yields. The greater height ratio, as given in Tables 

3 and 4; indicates the greater vigor of corn released' from the severe weed competition 

prevailing. Most of the simazine treatments, e.g., were twice as tall 

as the adjacent check row, 

The best treatments in terms of corn yield "rere the simazine treatments 

applied either pre-emergence or at emergence, and the ~NBP alone or in combination 

with dalapon applied at emergence. Dal.apon inj1lry occurred to the corn 

only at: the 2 pound rate, ~his injury was not reflected by any decrease in yields, 

Since DNBPfrequently fails to give adequate grassy \leed control this combination 

is. of promise Where both grasses and broadleaf weeds are present. 

TCBdid not adequately control mustard,' consequently did npt. perform satisfactorily 

in this experiment. The standard 2,4-D treatments were quite satisfactvry 

in this experiment where grassy weeds were not frequent.

..~- 

) 

) 

TABLE3. Effect of Pre-emergence Applications on the Yields of Silage Corn. 

Yield 

Treatment (Dry Matter) Plant Hgt. Treatment 

Number Treatment in cwt per A. Ratio* Number Treatment 

Yield 

(Dry Matter) 

in cwt per A. 

Plant Hgt. 

Ratio* 

1. 2j4- DA 1~ 54 1.3 11. Simazine 1 76 

2. 2,4-DA 3 71 1.4 12. Simazine 2 66 

3. 2,4-D E 1~ 42 1.4 13. Simazine 4 93 

4. 2,4- DE 3 95 1.3 14. TGB 1~ 50 

5. COM 3 35 1.1 15. TCB 3 54 

6. COM 6 48 1.1 16. Eptam 4 37 

7. Neburon 2 50 1.1 17. Eptam B 48 

8. Neburon 4 67 1.3 lB. Hani-wee:iJd Ck 63 

9. Diuron 1 64 1.2 19. Ck-not weeded 37 

10. Diuron 2 6B 1.2 

LSD 5% level 24.0 

* Ratio of average he Ight of treated plants to untreated plants -in same plot • 

1.5 

1.5 

1.5 

1.2 

1.5 

1.1 

1.0 

1.5 

TABlE 4. Effect of Emergence Applications on the Yields of Silage Corn. 

Yield 

Yield 

Treatment (Dry Matter) Plant Hgt , Treatment (Dry Matter) Plant Hgt. 

Humber Treatment in ewtper ~. ~l..(ltio* Number Treatm"lnt in c"rt per A. Ratio* 

. 

N 

l""\ 

.-l 

1. 2,4- DA 3/4 57 1.2 11. Da1+DNBP1+3 90 1.4 

2. 2j4- DIl 1~ 64 1.5 12. 1)al+DNl3P2+3 9B 1.4 

3. 2j4-DE 3/4 77 1~3 13. DNBP 3 86 1.3 

4. 2,4-DE li 70 1~4 14. DNBP 6 106 1.3 

5. Diuron 1 81 1.2 15. G30031 2 SO 1..4 

6. Diuron 2 66 1.2 16. G30031 4 70 1.4 

7. ATA i 40 1~1 17. Simazine 2 94 1.4 

8. ATA 1 63 1~3 18. Simazine 4 B7 1.6 

9. ACP1'15691 58 1.2 19. TCB 1~ 57 1.1 

10. ACPH569 3/4 52 1.3 20 • TGB 3 48 1.2 

.. LSD 5% level 19.6 

* Ratio of average height of treated plants to untreated plants in same plot.

I 

"" , 

,.; ; 

"" 

i 

i>1ean69 !1ean 78 

9O~ 

1- 

j 

I 

I 

I 

so: I 

Mean 63 

! I 

: 

Q) 

H 

;! 

Mean 66 

0 

01 

I 63 r: 

I 

H 

i r-1 

; I 

60~ o- Q) 

I 

j 

o, 

Hean 52 I i 

~ : I 

i 

- 

n 

0 

I 

I 

Mean 43 Mean 43 l'l I r- I 

or! 

I t- .- 

I 

II) 

~ 

4O~ 

.- 

37 

! 

I Q) 

or! 

I 

>-t ,; I 

t- 

I 

i 

~ 

I' 

I 

I I 

I ~ 

1 

I 

nj 

2 

°4 II 

, I 

, ' 

I 

I I 

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i I I ; 

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i I I 

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I I 

I! 

i I 

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j I 

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ij i I I 

I 

! I 

I 

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I 

l ! 

1 ,....., 

I I II n 

J 

I ! I I I i 

Non- 4 8 3 6 l! 3 li 3 weeded 1 2 l~ 3 1 2 4 

weeded Eptam CDM TGB 2,4-DA Ck Diuron 2,4-DE Simazine 

check 

CHEHICALTREATI·IENTS 

Pigure l. Effect of Pre-emergence Applications of Several 

l1erbicides on Yields of Silage Corn. 

) ) 

I 

I 

I 

I 

I

) 

) 

~. 

(Y\ 

rl 

f:: 

o 

m 

I-. 

2£ 

~ o 

s.:: 

or! 

III 

~or! 

>-t 

I 

I 

100 ~ 

! 

I 

! 

i 

I 

8O~ 

II 

; 

! I 

I i 

I I 

II 

, 

I ; 

I I 

I I 

;-1·- 

I ! 

i'ion- 

.Iean 52 

1-1 Mean53 

I I ,-i 

.I I 

-:I I I : 

Ijill' 

il I : 

Ii 

t ! I I 

"2 1 

ATA 

1 2 :3 

TGB 

I 

i I I 

'lI i 

j II:j I 

Mean 55 

lill 

i 

2374 

ACI'M369 

~1ean 61 

ill 

I I I 

; 

314 12 

2,4-DA 

Mean 74 

-. 

n 

i 

i j I I 

~711i2 

2,4-DE 

Mean 74 

r : 

I 

I 

I 

Mean75 

- I 

I ! 

.l;! 2 4 

Diuron G30031 

Figure 2. Effect of Emergence Application of Herbicides 

on Yields of Silage Corn. 

Mean 9+ 

~ 

~ 

Uu I 

1+3 2+3 "3 

Dal + DNBP 

Mean96 

~ 

6 

DHBP 

Mean , 

I' 

~ 

~ 

2 

Simaz:

135. 

WEEDCOMPETITIONANDCORNYIELDS 

Collins Veatch 1 

The trials reported in this paper were designed primarily to compare the 

weed controlling effectiveness of various chemicals when applied as pre-emergence 

and emergence sprays on corn. The design also per~ts a study of the relationships 

between weed index and yield, seasonal rainfall and yield, seasonal rainfall 

and weed competition as well as time of application and weed control. 

Materials 

and Methods 

The corn, U.S. 13, was check planted, 3 kernels per hill, on uniformly 

fertilized Wheeling sandy loam soil at Point Pleasant, West Virginia. Two row 

plots 10 hills long were sprayed with a power plot sprayer applying about 45 

gallons of spray per acre. Application rates are given in pounds per acre of 

active chemical. Yield was calculated in bushels per acre at l5.5~ moisture, 

correction being made for single and missing hills. The weed index used was 

based on a range of 0-9, 0 indicating no weeds present and 9 complete coverage 

of the plot by weeds. The weed index reported was taken at the time of harvest. 

The sprayed plots were given a post-emergence spray in 1957 to supplement the 

pre-emergence application. The check plots in 1957 were not cultivated or 

sprayed. In 1958 no post-emergence spray was applied but the checks were cultivated. 

Diuron treatments at 2 lbs. per acre reduced the stand of corn in 1958 to 

such an extent that the yields for this treatment were not included in the average 

or the calculation of the correlation coefficients. 

Discussion 

of Results 

A summary of the results of the weed control trials in corn at Point 

Pleasant in 1957 is given in Table 1. The rainfall during this season was 

comparatively low as indicated in the accompanying figure. The lack of moisture 

limited the yield and intensified weed competition as indicated by the 

average yield of 56.6 bu. per acre and the low yields of the checks where th~ 

weeds were not controlled. The correlation coefficient (-.76) between yield 

and weed index is significant at the 1% level. 

The growing season at Point Pleasant in 1958 was qUite favorable with an 

abundance of rain, well distributed, as indicated in the accompanying figure. 

Some of the chemicals gave satisfactory weed control in spite of the abundant 

rainfall. Even in the treatments with a high weed index the competition did 

not limit production as severely as in 1957 when moisture was a limiting factor 

during the grOWing season. 

1. Associate Agronomist, West Virginia Agricultural Experiment Station, 

Morgantown, West Virginia.

136. 

The 1958 results (Table 2) indicate that the application of a w~ed spray on 

corn at emergence, when the corn is in the seedling leaf stage, (early postemergence) 

was more effective than when applied pre-emergence. This is indicated 

by the average yields of 79.7 bu. and 94.13 bu. per acre for the pre-emergence 

and emergence trials respectively. The weed indexes are, with few exceptions, 

lower in the emergence than in the pre-emergence trial. Correlation coefficients 

were negative but very high between yield and weed index -.88 for the pre-emergence 

and -.97 for the emergence trial. They are both significant at the 1% level. 

Summary 

Applications of herbicides at emergence gave more effective weed control 

than pre-emergence applications as indicated by weed indexes, yields and correlation 

of yield with weed index. 

Weed compcti tion was more severe in 1957 thaIl in 1958. Yields were higher 

in 1958 than in. 1957. Abundan~ well distributed rain in 1958 compared to 1957 

made the difference. 

Good full season weed control was secured both ytiarsby the use of Simazine 

at the indicated rates. 

9 

Figure 1 

Rainfall - Point Pleasant, 1957 &1958 

._.}-957 

-.._.- 

--' 

O...l-_--.- __ ,........_-,-_--,- __ ..--_...,...._-, 

April May June July Aug. Sept. Oct.

137. 

TABLE 1 

1957 Yields and Indexcls of Weed Control in Corn Plots at Point Pleasant 

Pre-emergence 

May 15 

Rate Yield Weed Index* 

Ch-=mical Lbs/A. Bu/A. 0-9 

Check No Control 14.5 8.25 

2,4-D 1 56.5 1.25 

DNBP 4 52.5 1.88 

EPTC 5 50.5 1.50 

Novon 1 56.5 2.88 

Novon 2 51.5 1.38 

eDAA 4 57·5 2.00 

2,4-DB 1 56.5 1.75 


Simazine 2 57.5 0·50 

Simazine 4 67.0 0.25 

G-2790l 4 69.0 0.25 

Monuron 2 53·0 0.25 

Diuron 2 60.5 0.25 

Emid 2 53·5 0.75 

Amizol 2 48.5 2.2§ 


L.S.D •• 05 16.3 

Average Yield of 

Treated Plots 56.6 

Correlation cOcffici~nt between 

yield and weed index 

*Weed Index 0 - olean, no weeds 

9 - full plot coverage of weeds 

-.74

13S. 

TABLE 2 

1950 Yidds and Indext:.;s of W"ed Control in Corn Plots at Point Pleasant. 

Pre-emergence 

Emergence 

May 19 May 26 

Rate Weed Index* Weed Indliox* 

Ch",mical Lbs/A. Bu/A. 0-9 Bu/A. 0-9 

Che:ck Cultivated 98.3 1.75 103.6 3.00 

2,4-D 1 64.1 7.25 65.4 2.75 

CDAA 4 47.1 8.00 92.8 3.25 

DNBP 4 75.4 5.00 108.4 2.50 

EPTC 4 77·3 6.00 83.6 4.75 

EPTC 6 84.9 4.50 69.7 6.00 

2,4-DB 2 52.8 8.00 98.9 3·25 

2,4-DB 3 61.9 7.00 93.0 3;00 

Amizol 1.5 49·9 7.00 80.3 4.25 

Amizol 2 35.1 9.00 79·3 3.25 

Check Cultivated 97.8 1.50 101.0 1.50 

Emid 2 59.5 6.00 98.9 2.25 

Simazinc 0.5 107.4 0.75 107.7 1.25 

S1ma.zine 1 111.4 0.75 104.5 0.75 

Sima.zine 2 113·2 0.75 112.8 0'.50 

Neburon 2 80.5 6.25 98.7 2.75 

Neburon 4 ·99·0 4.75 107.7 2.25 

Diuron 1 108.0 0.75 94.6 1.25 

**Diuron 2 89.8 1.00 73.3 1.00 

Sesont) 4 80.5 4.50 103.7 1.50 

L.S.D •. 05 26.9 20·9 

Average of all plots 79.70 94.13 

Correlation coufficiunt b~tween 

yield and w"ed index -.88 -.97 

* Weed Ind"x 0 - clean, no weeds 

9 - full plot covt::rage of weeds 

** Diuron treated plots reduced the stand so severely that their results were 

not included in calculating the corrdation coefficient. 

Acknowledgement 

Acknowledgement is made to the following companicG who furnished the chemicals 

used in these trials: American Chemical Paint Company(AlvICHEM Products, 

Inc.), DowChemical Company, E. I. du Pont de Nemours and Company, Geigy 

Chemical Corporation, Monsanto Chemical Companyand th

139. 

PRE-EMERGENCE WEEDCONTROLIN SOYBEANs!! 

Henry W. IndY~ 

Weed control isa major problem in present-day soybean production 

practices.' Current cultural and mechanical practices are very effective 

means of combating the weed problem, but they have not been entirely adecpate 

or satistactoryunder the vario,us conditions with which a grower may be confronted.' 

Some degree of success has been achieved from research efforts 

directed toward a reliable and eoonomic means of chemical control'cut'£or the 

most part progres,s has been cornparati vely slow. Fur~hermore, ,the limi tf)d 

number of recommendations for chemical control of weeda in soybeans are not 

receiving very rapid acceptance in their respective areas because in many 

cases of the inconsistant results ~ether with the prohibitive cost of 

material. Chemical control of undesirable weed growth in. soybeans continues 

to be a. weed-crop situation in need of. further investiSation. 

The results of a three-year study conducted in Delaware were reported 

in 1957 (Proceedings 11th Annua;J.Meeting NEWCC,Jan. 1957) ~ The present 

report is a summaryof .th~ results obtained during the two year period, 

1957-58. " . 

Pr$;gedure 

Various herbicide!! applied as pre-emergence treatments were evaluated 

at Georgetown and Newark, Delaware, in 1957 and 19.58. The soil type at 

Georgetown (southern location) was a Norfolk loamy sand and at Newark 

(northern location) a Sassafras loam. The herbicides and respective rates 

of application which were included in the tests are indicated in Tables 1 

and 2. 

The Wabash variety of soybeans was seeded in rows at a depth of 105 

inches and at the rate of 40 pounds of seed per acre. Individual plots consisted 

of 4 rows,. each row 15 feet long and spaced 3 feet apart. One day 

after seeding of soybeans, each herbicide was applied at the specified rate 

with a modified, bicycle-type experlmentalplot sprayer at a pressure of 

30 psi. The. low 'concentration of each herbicide was applied in water solution 

at the rate of 20 gal./A. Plots receiv:l.ng the double concentration of 

herbicide were sprayed twice using the single rate calibration on the sprayer. 

Broadleaf weeds which predomindatedincluded pigtfEled (Amaranthus retronexus), 

ragweed, (Ambrosia artemisiifolia) and lambls quarters (ChenopO'diUiii 

album). Crabgrass (Digitaria spp ., was the predominant grass. 

Weed control ratings and soybean stand counta were taken 35days after 

the application of chemical treatme~ts. During the remainder of the season 

all plots were cultivated as needed to control weeds. General]y, this recpired 

1 or 2 cultivations per season. The plots were harvested in the fall 

for yield data. 

11 Niscellaneous Paper No: 321., Delaware Agricultural Experiment Station.

Results 


Soil moisture at Georgetown in 1957 at the time of planting, although 

adequate foz: ~ermination of soybeans as well as weeds, was slightly deficient 

and marked tllEl beginning of a prolonged drought period which prevailed throughout 

most of the season. At Newark slightly better but very similar moisture 

conditions prevailed. In contrast, the 1958 season at both Georgetown and 

Newark was characterized by very satisfactory soil moiBturethroughout the 

entire season. 

The performance of the herbicides evaluated at Georgetown and Newark 

is summarized for 1957 in Table 1 and for 1958 in Table 2• Weed control 

ratings and soybean yield data indicate that NaPCPat 25lbs./A. was very 

satisfactory in the control of broadleaf weeds at both locations during the . 

two years of this study. The results support the evidence previously reported 

for the three year period 1954-1956 which indicated the consistant satisfactory 

performance and superiority of NaFCPfor pre-emergence broadleaf weed control 

in soybeans. Control of grasses was only fair and not entirely satisfactory •. 

Premerge at 6 lbs./A. also was effective in controlling broadleaf weeds. 

Previous results with this material have been variable depending upon environmental 

conditions, particularly temperature and soil moisture. 

Etnid at 2 lbs./A. has shown considerable promise for the control of both 

broadleaves and grasses. The stunting andepinasty ot the soybean seedlings 

which was very apparent during the early growth stages was outgrown in J,ater 

stages of development. The data indicate no significant reduction in yield of 

soybeans. Further evaluation of this chemical is needed. 

In the control of grasses, the carbamate materials were very effective. 

Considering the two yearls results at both locations, Randox was superior to 

Vegadex in controlling the grasses. Poor control of broadleaves was obtained 

from both of these herbicides. The results indicate better weed control 

under the more moist conditions characteristic of the 1958 season as compared 

to the less favorable soil moisture of the 1957 season. In this respect it is 

interesting to note the performance of Eptam. This chemical showed better 

control under the less favorable soil moisture conditions. At 6 lbs./A. 

Eptam gave better control of grasses than either Randox or Vegadex in 1957 

and compared very favorably in 1958. In addition, Eptam was more effective 

than Randox or Vegadex in controlling the broadleaves. The soybean seedlings 

were stunted during the early growth stages but this ef'fectwas rapidly 

overcome by new growth. The yield of soybeans was not affected. 

In comparing all the herbicides evaluated in these trials the best control 

of both broadleaves and grasses without any reduction in yield of soybeans was 

obtained from a mixture of NaPCPat 25lbs./A. and Randox at 8 lbs./A. However, 

from a practical standpoint, the cost of this treatment would be prohibitive 

for use on soybeans.

141. 

Summary 

Various herbicides were evaluated for pre-emergence weed control in soybeans 

at Georgetown and Newark, Delaware, during 1957 and 1958. 

Excellent control of broadleaves was obtained with NaPCPat 25 lbs./A. 

Satisfactory results were also obtained with Premerge at 6 lbs./A. Emid at 

2 lbs./A. appears to be promising on broadleaves and grasses. 

Randox was effective in the control of grasses but the results varied 

between seasons as a result of soil moisture. This herbicide was more 

effective under the more favorable soil moisture conditions. In comparison, 

Eptam was superior to Randox during the dry season and only slightly less 

effective during the more moist season. Fair control of broadleaves was 

obtained with Eptam whereas the results were poor with Randox, 

The most effective treatment for the control of both broadleaves and 

grasses was a mixture of NaPCPand Randox. 

-Acknowledgements 

The cooperation of the following companies in providing the chemicals 

necessary for these trials is gratefully acknowledged. 

AmchemProducts';Inc., DowChemical Co., Geigy Chemical Corp., Nonsanto 

Chemical Co., Naugatuck Chemical Co., and Stauffer Chemical Co.

) ) 

Table 2. The e1"1'ect.of pre-emergence herbicides on weed cont.rol, soybean stand, and soybean yield at 

Georget.ownand Newark, Delaware - 1958 

Geo e wn Newark 

Treatment. Rate WeedControl Bat· Soybean Soybean WeedControl Ratina-- Soy~ Soybeaz 

1bs./A. Broad- Grasses Stand Yield Broad Grasses Stand Yield 

leaves Reduction Hu./A. leaves Reduction 9J../A. 

% % 

Alanap-:f 2 3.0 1.0 0 20.1 2.7 2.7 0 35.5 

n 

4 6.0 4.3 0 27.5 6.0 4.3 0 39.8 

Randox- 4 0 703 0 27.6 0 5.0 0 35.4 

II 

8 2.3 9.0 0 29.2 3,,0 8.0 0 32.7 

Vegadex 4 0 4.7 0 23.4 0 2.0 0 38.1 

- " 8 1.7 6.1 0 26.8 2.3 6.0 0 32.4 

Eptam J 3.7 6.3 0 29.9 3.0 5.7 0 35.6 

n 6 7 8.1 0 29.5 7.0 7.3 0 40.4 

NaPCP 12.5 5.3 103 0 32.7 5.3 2.7 0 42.0 

II 

25 8.3 6.3 0 32.8 9.0 6.3 0.8 39.6 

NaPCP+ 12.5 5.7 6.7 0 29.3 7.7 7.3 0 39.9 

Randox 4 

NaPCP..: 25 9.3 8.7 0 32.8 9.0 8.7 0 40.3 

Randox 8 

NaPCP+ 12.5 4.7 6.0 0 30.7 7.3 5.7 0 25.0 

Vegadex 4 

NaPCP+ 25 9 1.3 0 29.9 8.1 8.0 0 31.9 

Vegadex 8 

pr.emer~e 3 6.3 2.7 0 31.9 1.0 3.0 0 31.3 

~.. It 

6 8~O 1.3 0 31.6 8.0 7.3 0 40.5 

Emid 1 1.0 5.3 0 25.7 8.0 1.3 0 37.4 

" 2 -9.3 8.0 0 28.0 9.1 8.1 1.5 39.7 

Check~ - 0 0 0 17.2 0 0 0 36.4 

Check3 - 7.3 1.3 0 31.1 8.0 8.0 0 41.2 

LSD .0) 2.8 NS 

.01; NS NS 

!I ~-.¢Ont.rolrating: 0 - nocontro1, lO- perfect control. 

. 

Ch~c ;;;_cultivation ident.icalto chemically treated plot. CheckY' - cultivation as needed commencing 

(\/ " at time of planting. 

-:t 

M

C'\ · 

...;;t 

r-l 

Table 1. 

Treatment 

Alanap-3 

" 

Randax: 

" 

" 

Vegadex 

Eptam 

n 

NaPCP 

" 

NaPCP + 

Randox 

NaPCP + 

Randox 

NaPCP + 

Vegadex 

NaPCP + 

Vegadex 

Premerge 

" 

" 

" 

CP 6936 

G 30031 

2,4-n PGBE 

" 

ChecJ#, 

chec0 

The effect of pre-emergence herbicides on weed control, soybean stand, and soybean yield at 

Georgetown and Newark, Delaware - 1957 

Rate 

lbs./A. 

2 

4 

48 

4 

8 

3 6 

12.5 

25 

12.5 

4 

25 

8 

12.5 

4 

25 

8 

3 6 

3 

6 

2 

40.5 

1 

George 

Weed Control Ratin 

Broad- Grasses 

leaves 

4.0 

6.7 

0.7 

2.3 

2.0 

4.3 

2.3 

6.0 

6.0 

8.3 

5.3 

8.3 

4.3 

6.0 

5.0 

7.7 

4.7 

7.7 

5.3 

8.3 

4.7 

7.0 

7.7 

9.3 

,wn 

Soybean 

Stand 

Reduction 

% 

9.6 

8.9 

7.2 

14.0 

9.6 

14.0 

o 

6.4 

o 

0.8 

o 

8.1 

Newark 

Soybean tfeed Control Rati 

Yield Broad- Grasses 

Bu../A. leaves 

10.5 

lOS 

6.8 

6.2 

5.1 

10.2 

7.5 

10.9 

10.1 

17.1 

13.4 

1505 

1.0 

8.3 

2.0 

3.1 

2.1 

4.0 

1.3 

8.1 

1.7 

9.0 

5.3 

1.1 

4.3 

6.0 

4.0 

6.0 

8.1 

10.0 

6.0 

7.1 

Soyoean 

Stand 

Reduction 

% 

o o 

1.8 

o o o 

14.7 

Soybean 

Yield 

Bu../A. 

35.1 

33.8 

28.5 

26.7 

31.1 

32.0 

39.6 

39.3 

39.4 

31.9 

3.0 

8.0 

4.7 

8.3 

1.3 

18.6 

9.4 

11.2 

7.7 

9.0 

6.7 

8.3 

0.3 

15.9 

38.5 

37.9 

6.7 3.7 19.6 11.9 6.3 4.7 0.1 40.2 

8.3 6.7 10.6 16.7 8.3 7.0 0 40.5 

3.3 5.0 1405 11.2 3.0 

·6.3 

5.0 0 30.6 

7.3 11.1 15.5 5.3 7.7 0 29.8 

5.3 3.3 8.2 11.5 8.0 7.1 99.4 1.8 

7.7 5.7 5.2 13.8 9.0 9.0 100 0 

6.0 2.3 7.0 37.2 

8.3 4.1 18.3 36.0 

o 0 0 6., 0 0 0 28.7 

8.0 8.0 0.6 12.9 8.0 8.0 2.1 38.2 

LSD .05 4.6 7.9 

.01 «.» - -- 10.6 _. 

af H~~d control rating: 0 - no control, 10 - perfect control. 

CheekY - cultivation identical to chemically treated plot. Check?! - cultivation as needed commencing at tj 

of planting. 

)

144. 

Effects on Oats of Several Herbic:ides Applied. on 

Under-seeded Legumes 

Robert A. Peters 

1 

and Warren G. Wells 

Since the advent of 4(2,4-DB) there has been a renewed interest in weed control 

in legume seedings. While the possibility of making forage seedings without 

& small grain companion crop now seems feasible on manyfarms seedings will continue 

to be seeded in grain. In the following experiment, the effect of several 

hel'bicides on yields of an oat companion crop were evaluated. 

Procedure 

The experiment was conducted on the AgronomyResearch Farm of the Storrs 

(Conn) Agricultural Experiment Station. Seedings of legumes were made with a 

grain drill on May 16, 1958 in a companion crop of Clinton oats seeded at the 

rate of 1,bushels per acre. 

A randomized block design was used, replicated three times. Individual plot 

size was 5 by 12 feet. Treatment comparisons were made by use of the Duncan's 

Multiple Range test. Listed below are the chemical treatments applied on June 13, 

1958. The oats averaged six inches in height and were still in the til~~ring stage. 

TABLE 1. 

Chemicals Used in Experiment 

CollD!lOnName 

2,40-DA 

MeP 

4(2. 4 DB)amine 

4(2, 4 DB)ester 

DNBP 

Dalapon 

DilJ1"on 

Neburon 

Chemical Name 

2.4-dichloro phenoxyacetic acid, amine salt 

2,chloro-4-methylphenoxyacetic acid, amine salt 

4(2.4-dichlorophenoxy)butyric acid, diethylamine 

4(2,4-dichlorophenoxy)butyric acid, ester 

dinitro-o-sec-butylphenol,.alkanolamine 

2,2-dichloropropionic acid. sodium salt 

3(3.4-dichlorophenyl-l,1-dimethylurea 

3-(3,4-dichlorophenyl-l-methyl-l-N-butylurea 

SOurce 

Dow 

Dow 

Amchem 

Amchem 

Dow 

Dow 

Dupont 

Dupont 

Chemical treatments .were made on June 13, 1958. Applications were made in 

40 gallons of solution per acre using a bicycle type sprayer. The oats averaged 

six inches in height at the time of' application and were still in the tUlering 

stage of growth. The predominate weed species were conmonchickweed (Stellaria 

media), yellow foxtail (Setaris lutescens), and barnyard grass (Echinochloa crusgalli). 

lAssociate Agronomist and Researoh Assistant, respectively, University of Connecticut, 

Storrs, Connecticut.

145. 

The oats were harvested on August 12, 195$ when the oats were in the late 

dough stage. After 

threshing machine. 

drying the oats they were threshed in a small power driven 

~~ ~ Discussion 

Treatment effects became evident quite early in terms of plant stunting and 

somewhat later as morphogenic responses. Stunting was caused by the lk lb. rate 

of dalapon or any treatment including dalapon. The addition of 2,4-DB amine 

caused the llIOst severe stunting; up to 50% in some plots. 

I'lorphogenic effects were evident following the use of either rate of 2,4-0 

or 2,4-DB ester. The activity of the latter was quite markedly greater than the 

corresponding 2,4-OB amine at comparable rates. Some activity was seen, however, 

at the 2 pound rate of 2,4-0B amine. The leaf blades of' ei'.t'ected plants were 

narrowed and curled and tended to grow more upright than the normal leaves. 

The yields of threshed oats are given in Table 2. There was a close correlation 

between injury noted in the field and the o~t yields obtained. 

TABLE2. Yields of Oat Grain Following Chemical Treatment 

Treatment Rate Bu/l) Bu weight Treatment Rate BU/A" Bu weight 

Check 40.1 25.$ 2,4-DB amine + 

2A-DA 1/2 35;1 25~6 dalapon 

24.$ 23~$ 

2,4-DA 1 33.$ 24.6 DNBP+Oalapon 

l

146. .:» 

The 2,4-DB ester treatments caused a severe reductio'ri in yield at both rates 

with the yield at the 2 pound level only 70%that of the check, Other treatments 

causing a significant reduction in yield included the high rate (li) of dalapon, 

alone and in combinations ,'lith 2,4-DB and 2,4-F>, The DNBP-dalapon l~ combination, 

,lhile not significantly lo"rer at the ,05 level, was definitely lO"-"lr, The 2,4IIlOB 

amine formulation alone gave some yield reduction but much less than the ester 

formulation, It is noteworthy that no significant reduction was obtained from a 

1 pound rate of 2,4-D which indicates that the oats were not treated at a sensitive 

stage of growth. 

Effects 

~ ~ Weights 

Volume weight determinations were made to determine the influence of treatment 

upon the endosperm development, Decreased weights relative to amount of 

glumes as indicated by bushel weights followed the same pattern as the yield reduction 

with significant reductions over the best yields obtained being obtained 

from 2,4-DB ester at 3/4 and 1:1pounds and from the combination of dalapon at l~ 

pounds per acre with 2,4-DB amine at 2 or with 2,4-D at 1 pound per acre. While 

dalapon caused stunting, there was little evidence 6f delayed maturity. 

Summary 

Reductions in yields of threshed oats and of bushel weight followed the 

application of 2,4-DB ester at 1 or 2 pounds per acre 1n the late tillering stage. 

;!uch less injury was' obtained from 2j4-DB amine. When dal.apon at l~ pounds was 

used alone or with 2,4-DB amine or 2,4-D, damage was also severe, a direct indication 

of injur.y from the higher rate of dalapon.

lAssociate Research Specialist in Turf Management; Assistant 

Research Specialist in weed Control; and Research 

Assistant, Department otFarm Crops, Rutgers-The state University, 

New Brunswick, N. J., respectively. 

147. 

INFLUENCEOF WINTERANDSPRING APPLICATIONSOF PRE-EMERGENCE 

HERBICIDESON CONTROLOF CRABGRASS 

R. E. Engel, W. F. Meggitt, and J. R. Fulwider 

The development of pre-emergence crabgrass herbicides has 

raised a question concerning the effect of time interval between 

application and germination. No research information 

is available on this question. Three tests were made during 

the winter of 1957-58 and the spring of 1958 to determine the 

effect of season of applying chlordane and lead arsenate for 

crabgrass control. 

Procedure 

Three pre-emergence crabgrass tests concerning time interval 

between treatment and germination were established 

in the winter of 1957-58. Test area I was composed of a 

mixed turf of Kentucky bluegrass, red fescue, and colonial 

bentgrass cut to 3/4 inch and seeded with crabgrass in 

early December 1957. Test II waS located on 1/2 inch turf 

of bentgrass and annual bluegrass that had a natural source 

of crabgrass seed. Test area III was located on a golf 

course fairway that had a moderate supply of crabgrass. 

Treatment dates for the respective tests were: December 24, 

March 11, and May 14; December 24, April 4, and May 24; and 

March 13, April 18, and June 2. 

The chemical treatments used were chlordane at 40, 60, and 

80 pounds per acre on granular attaclay; chlordane at 40 pounds 

per acre on an organic carrier; chlordane at 60 pounds per 

acre on vermiculite; lead arsenate at 871 pounds per acre 

and an arsenical complex* at 1350 pounds per acre. 

Plots were 3 x 14, 3 x 12, and 3 x 12 feet for the respective 

tests. All treatments were replicated three times. 

Test area I was treated in late May with a complete fertilizer 

at a rate that supplied one pound of nitrogen per 1000 square 

feet and mowed at 1/2 inch through the season. Test area II 

was not fertilized during the fall of 1957 or in the 1958 season, 

was mowed to 1/4 inch from late spring through the summer, 

and received supplemental water during July and August. 

Test area III received standard fairway maintenance. The effect 

of the treatments on the crabgrass stand was determined 

by plant counts within a 2 x 10 feet area in the center of 

each plot on September 29, September 24, and October 25 for 

the respective tests. 

1

148. 

Results 

Chlordane gave its best pre-emergence crabgrass control 

when applied during the period of March 11 to April 18. 

Chlordane on organic matter (Test I) have the same degree of 

crabgrass control at all dates of treatment. Lead arsenate 

gave slightly better performance from the earliest applications. 

The arsenical complex gave its best perfo~ance with 

the earliest applications. 

The 80 pounds per acre application of chlordane gave the 

best and most consistent crabgrass control. Sixty pounds per 

acre application of chlordane on granular attaclay gave good 

control except in Test III when applied during the period of 

mid-March to mid-April. Chlordane on vermiculite performed 

similarly to chlordane on grarlular attaclay. The 40 pounds 

per acre rate of ch:i.ordane gave good crabgrass control on 

the March 11 treatment of Test I only. 

The crabgrass control given by the arsenicals was generally 

poor. The arsenical complex treatment gave good results 

on the first two dB.tes of Test III. In part this may 

have been the result of the nitrogen contained in the treatment, 

since the test area received no other fertilization 

during the fall of 1957 or the 1958 season which greatly reduced 

the density of turf cover. Temporary discoloration 

resulted from treatment with the arsenical complex preparation. 

~:1£1ary 

Three rates of chlordane on dry carriers, lead arsenate, 

and an arsenical complex were applied at different seasons 

to three different turfgrass test areas for pre-emergence 

crabgrass control. The results were as follows: 

1. Chlordane gave best crabgrass control when applied 

during the period of mid-March to mid-April. 

2. The lowering of the rate of chlordane from 80 to 60 

and 40 pounds per acre increased the need for 

specificity in the date of treatment. 

3. Chlordane applied at 80 pounds per acre gave the 

best and most consistent crabgrass control of the 

test treatments. 

4. Chlordane on granular attaclay and vermiculite gave 

similar results at 60 pounds per acre. 

5. The arsenical treatments generally gave their best 

crabgrass control with winter application. The 

crabgrass control produced by lead arsenate and the 

arsenical comnlex werp- lmSR.t1sf'R~tn,..v "'YM~Tlt f'nY'

149. 

i're"TChern.c aLa Por Pr-e-Emer-gence Crabgrass Control 

John E. Gallagher and Richard J. Otten 

Ar.lchem Products. Inc. lllnbler. Pa. 

Greenhuuse and field screening trials in 1957 indicated that 

DI~OoSN (2.5-dichloro-3-nitrobenzoic acid) had the properties of 

a good pr-e-s eraer-genc e crabgrass control chemical. 'l'herefore. an 

experiment Has desiLned comparing rates of application. n~~ber of 

treatments. and treatnent intervals. :,tandard materials 8S 11011 

as two other new experimental chemicals were included in this 

test. 

The test was located at the Oak Terrace Country Club. ,~bler. 

~a. rhe plots were laid out on a site that normally has a high 

population of crabGrass. The turf was a mixture of broadleaf 

weeds, Kentucky bluegrass and patches of creeping bent. Plot size 

was 6' by 10'. Treatl.1ents were replicated three times and 

randomized. Fifteen check plots were included in the plot layout. 

! -aterials nate of ~ctivc InGredient 

1- 

2- 

3- 

4- 

5- 

DIlWBEH (l,CP-Jl-503) 

2,5-dichloro-3-nitrobenzoic 

DHICBElr 

(3% on vermiculite) 

CHLORDiUJE 

(76% emulsifiable technical 

chlordane) 

CHLORD.HlE 

(8% technical 

verm1.culite) 

chlordane on 

acid 

PAX 

(lead arsenate. 

chlordane) 

arsenous oxide, 

~.4,6.8,10 lb/A (liquid) 

6.8.10 lb/A (dry) 

60 lb/A (liquid) 

60 lb/ll (dry) 

549 lb/A-:~ (dry) 

(half recon~ended rate) 

6- 2,4-D/2.4.5-T (esters in 2/1 ratio) 3 lb/A (liquid) 

7- ALAl!APIF 

(H-l naphthyl phthalamic acid plus 

urea) 720 lb/M (dry)

150. 

iJaterials 

8- ACP:a:c 707 

(2-chloro-4-fluoro phenoxy acetic 

ac Ld) 

~ of fIctive Inrredient 

1,2,3 lb/A (liquid) 

9- F.\i:L.C S (ACP-ii-673) 

2,3,6-Trichlorophen71acetic 

sodium salt 

10- F":HAC up (ACP-~I-674) 

2,3,6-Trichlorophenylacetic 

amide 

11- FEHAC E (ACP-i'1-675) 

2,3,6-Trich1orophenylacetic 

ester 

':

151. 

'~l-fLOFiL ..J!~;, at 60 pound .Jer acre was mor-e effectl.ve as a llr:r 

f'or-rru.l ab Lon than as a spray. 

~AX was ineffective. This may be explained by the fact 

t'v't only one-ch a'Lf the recommended rate was applied. 

:lunmary 

'l'he 2,4-D/2,4,5-T nixture and the XF 707 were ineffective. 

DIHOBCN is an effective pre-emerf.ence crabgrass control 

c.rera l c a'l , but 2 to 3 a~)'-'lications of 8 to 10 pounds per acre are 

needed to provide satisfactory control. 

CHLOHDiuC results in this test, crabgrass control in the 

r-ange of 50-75jj with a single application of 60 pounds ner acre, 

acreed with test results from other ~ ,rts of the count~y. 

[t'i,I

..,~, 

152. 

fable I. I) r. :tiiit!.J.i.JJeries Percent Grabtrass Gontrol Jl.ULust 28, 

1958.-:

153. 

lable II - 

:JlHOB'!,N :Jeries --- Percent Jrab[,rass Control, AUQust 28, 

1958.:< 

Conparison of Rates, l{Ulilber of 'I'r-e atmerrt s and 

Treatment Intervals 

DIlKB'~l'l 

DRY 

3 week intervals Pounds per acre 

No. treatments 6 8 10 ..iver9..ge all rates 

1 Apr. 3 -18 -7 26 Oc' 

iO 

2 Apr. 2L~ 45 33 73 50/~ 

3 >ay 15 65 65 70 66~~ 

4 

',leek intervals 

No. treatments 

1 Apr. 3 -18 -7 26 or i ;" 

2 l!ay 1 45 68 73 61:"; 

3 Hay 29 64 92 76 77% 

6 Heek intervals 

~'o • t r-eatment s 

1 Apr. 3 -18 -7 26 0'; ;' 

2 day 15 65 65 70 66;·& 

3 June 26 38 10 68 36;& 

-:

154. 

'I'ab l,e III i\dcJit ional Chera Lc al.a --- Percent Crabgrass Control 

.!-~ucust 28, 1958·:~ 

Comparison of Oomner-ci al .'roducts and Other 

Experimental Lat er-La'l a 

.. uterial Rate/acre Number 'rreatment .'ercent 

Treatment Interval Control 

CriLORDIiilE 

liquid 60 lb. 1 56 

dry 60 lb. 1 78 

PAX ( -:H~) 549 lb. 1 2 

2,4-D 

2 lb. 

2,4,5-T 1 lb. 1 -15 

I,CP XF 707 1 lb. 1 -45 

2 lb. 1 6 

3 10 .. 1 -67 

lilanap IF 720 lb •. 3 4 "Heek 41 

l"ENACS 

(ACP-li- 673) 3 lb. 1 85 

6 lb. 1 97 

ft'Ei.iACl'P 

(ACP-11-674) 3 lb. 1 86 

6 lb. 1 98 

FENACE 

( 'WP-II-675) 3 lb. 1 45 

6 lb. 1 68 

Control 00 

-::·Percent control figure is based on the crabgrass cover in 

treated plots compared to the crab6rlss cover in check plots. 

The average crabgrass cover in 15 check plots "Has 42.5%. 

Underscored figures __ ) indicates satisfactory control of 75% 

or better ..

155. 

CrabgN1;s Control with Pcs~nee Chemical Tl-Htm~ 

J. R. Kollett and J. A. Defrance 2 

Rhode Island Agricultural Experiment Station 

Kingston, Rhode Island 

Previous tests with chemicals such as the mercurials and 

arsenicals have proven effective" for the' purpose of' postemergence 

crabgrass control in lawn turf ll,2,3,4). The object 

of this investigation WRS not only to determine the comparative 

effectiveness of several materials commercially 

available at present but aLso to' evaluate several newer materials 

in respect to their possible use for post-emergence 


.Materials 

and Metho£a 

. This experiment was conducted during the summer of 1958 

on five-year-old lawn turf on the University of Rhode Island 

campus. The test plots were 50 square feet in area, replicated 

three times and located on a soil classified as a fine 

s~ndy loam of pH 5.9. The turf, composed of Red fescue, 

Kentucky bluegrass and Colonial bentgrass, was heavily infested 

with smooth crabgrass (Digitaria i§chaemum). A oneinch 

height of cut was maintained and no supplemental water 

was applied. Precipitation was adequate throughout the entire. 

growing season. 

The herbicidal materials used, the percent active ingredient 

in each compound and the rates of application were 

as follows: 

A. 

c. 

D. 

Granular Material.A (Mercury-.in the form of phenyl 

mercury salts of acetic, propionic 

and naphthyl phthalamic as metalic 

0.25% N-l naphthyl phthalamic acid 

0.24%) applied with a calibrated 

spreader at 2.4 and 4.8 pounds per 

1000 square feet. 

Granular Material B (Disodium methyl arsonate hexahydrate 

2.5%) applied with a calibrated 

spreader at the rates of 3.6 and 

7.2 pounds per 1000 square feet. 

Neburon (18.5% 3-(4 dichlorophenyl.2-methyl-l-N-butylurea) 

at 3 oz. per 1000 square feet. 

DMA(44% disodium methyl arsonate) at the rates of 1/6 

and 1/3 of a pound per 1000 square feet. 

-------------------------------- 

lContribution No. 964 of the Rhode Island Agricultural Experiment 

Staticn_

156. 

F. 

Liquid Material A~~ (8.0% octyl ammoniummethyl arsonate 

_ and 8.0% dodecyl ammoniummethyl 

arsonate) at the rates of ·1/4 and 1/2 

. of a pound per 1000 square feet. 

p~ (10% phenyl mercuric acetate) at the rates of 2.0 and 

2.5 oz. per 1000 square feet. 

The dry formulations, namely Granular Materials A and S, 

were applied with a calibrated spreader to ensure correct application 

and uniform distribution. All other materials were 

appl dad in a water solution at the rate off> gallons per 1000 

square feet with a powerized pressure sprayer. 

The first treatment was applied jUly 24 when 

plants were in the two and three leaf stage. The 

last application was on August 1st, approximately 

the first treatment. 

the crabgrass 

second and 

one week after 

The percent crabgrass within the individual plots was taken 

JUly 24 just prior to the first application and again on October 

17 at the conclusion of the experiment. 

Results 


The results obtained from this study are summarized and 

the data presented in Table 1. All rates ware on the 1000 

square foot basis. Granular Material A when app.Lied at double 

the recommended rate of 4.8 pounds was 97% effective in control 

and only slight discoloration resulted from the first treatment. 

This increased to moderate following the second treatment, however, 

no permanent injury resulted. Seventy-two percent control 

was obtained with Granular Material A at the rate of 2.4 pounds. 

Granular Material B produced 100% control of crabgrass both 

at the recommended rate of 3.6 pounds and at double the rate of 

7.2 pounds. No apparent advantage was noted from the higher 

rate since both were equally effective. Discoloration was 

greater at the higher rate although no permanent injury was 

noted at the conclusion of the experiment. 

Neburon at the rate of 3 ounces per 1000 square feet did 

not reduce the incidence of crabgrass to any significant degree. 

DMAat 1/6 and 1/3 of a pound provided 93% and 97% control 

respectively. The 1/3 pound rate produced moderate discoloration 

with the first treatment and severe discoloration resulted after 

the second treatment was applied eight days later. However, discoloration 

in both cases was only temporary and no permanent 

injury resulted. The 1/6 pound rate ofDMA resulted in only 

slight discoloration following each of the treatments. 

As in previous craQg:J:ass control studies conducted at the 

Rhode Island Agricultural Experiment Station, p~ at recommended 

rates of 2 and·2.5 ounces produced 98% and 100% control. The 

hiaher rate of 2.5 ounces caused moderate discoloration and the 

-;»:

lower rate caused only slight discoloration. In neither case 

was there any indication of injury at the end of the experimental 

period. 

In 1958, the relatively new ammoniummethyl arsonate 

compounds were available commercially for control of crabgrass. 

Liquid Material AMAwas applied at the rates of 1/4 

and 1/2 pound per 1000 square feet. 80th rates resulted in 

100% control of crabgrass with only slight discoloration 

resulting after each of the two treatments. 

SUmmarysnd Conclusions 

During the summer of 1958 a post-emergence crabgrass study 

on lawn turf was conducted at the Rhode Island Agricultural Experiment 

Station. All materials at the various rates were applied 

twice. The first application was applied on July 24, 

when the crabgrass was in the two and three leaf stage and the 

second on August 1. All rates were on the 1000 square foot 

basis. 

Two treatments of Granular Material A at the rate of 2 04 

pounds provided 72% control compared to 97% control at the 

double rate of 4.8 pounds. Granular Material 8 at 3.6 pounds 

and at 7.2 pounds produced 100% control in each case. Greater 

discoloration resulted from the higher rates however no permanent 

injury was noted at the conclusion of the experiment. 

Dh~ and Liquid Material AMAboth provided exceptionally 

good control. Only slight discoloration occurred on the Liquid 

Material AN~ plots even at the higher rate whereas moderate to 

severe discoloration was noted with DMA. 

PMA(10%) at the rates of 2 and 2.5 ounces produced 98% 

and 100% control respectively. No serious discoloration or 

injury was noted. 

Neburon did not provide control at the rates used in this 

study. 

None of the materials showed any severe injury for any 

length of time at the rates used. 

Results indicate that the best time to apply materials for 

crabgrass control is when the plants are young or in the 2-3 

leaf stage and before they begin to spread out over the lawn. 


The authors wish to express their appreciation to the 

following for their contributions to this study: The Clapper 

Co., E.l. duPont de Nemours and Company, W. A. Cleary Corporation, 

O. M. Scott and Sons Company, The Upjohn Company and the 

Vin~l~nn r.nmn~nv_ 

157.

158. 

Litergiure 

Cit~d 

1. DeFrance, J. A. and J. A. Simmons. A comparison of chemicals 

for crabgrass control and a study of some factors 

related to the control of crabgrass with phenyl mercury 

compounds. Proc. 6th Annual Meeting, NEV~CC, pp. 67-75. 

Jan. 1952 0 

2. Gallager, J. E. and B. H. Emerson. Disodium methyl arsonate 

vs. crabgrass. N.Y. State Turf Assoc. Bul. No. 51, PP. 

95-96. 1955. 

3. Hart, S. W. and J. A. DeFrance. Post-emergence crabgrass 

control with chemicals in lawn turf. Proc. 10th Annual 

Meeting, NEWCC,pp. 61-67. Jan. 1956. 

4. Wisniewski. A. J. and J. A. DeFrance. Post-emergence control 

of crabgrass in lawn turf with chemicals. Proc. 

11th Annual Meeting, NEWOC,pp. 151-155. Jan. 1957.

( ( 

Table 1 0 

Post-emergence control of crabgrass in lawn turf. Rhode Island Agricultural Experiment 

Station, 1958. 

- - - - - - - - - - - - Rate- - -%-Crabgrass- %Cra"bgrass - - - - - - - - - - ~ - - - - - - - - - 

Material per 1000 before after % Discoloration* 

____________ 59..ftJl.. __ Ir( ~a:tm~nt) __ Tf.es.tmentr _ Qon.t!:,o.l _ ;[ulY _3Q. _ ~u~. _8 __ 0.c.t ....F_ 

..July 24 (Oct , 17 

Granular Material A 2.4 Lbs , 32 9 72 1.0 1.0 0.0 

Granular Material A 4.8 Ibs. 30 1 97 0.7 2.2 0.0 

Granular Material B 3.6 Ibs. 33 0 100 0.5 T 0.0 

Granular Material B 7.2 Ib5. 38 a 100 2.3 1.8 0.0 

Neburon 3 oz. 29 39 00 0.0 1.7 0.0 

DNA 1/3 Ibs, 28 2 93· 2.5 3.8 0.0 

DMA 1/6 Ibs , 31 1 97 1.7 1.3 0.0 

Liquid Material ANA 1/2 lb. 31 a 100 1.2 1.2 0.0 

Liquid Material ANA 1/4 lb. 24 a 100 0.4 T 0.0 

PMA 2 oz. 41 1 98 r.o 1.5 0.0 

PMA 2.5 oz. 40 a 100 2.3 2.3 0.0 

None --- 32 98 00 0.0 0.0 0.0 

*DIscoloration-index: T ~ trace, -0-= -none, -1-= -slight, -2-= -moderate, -3-= -severe, -4-= -very severe, 

5 = permanent injury. 

Treatments were applied July 24 and August l~ 

..... 

Vl 

-o

160. 

CHICK\~EED 

CONTROLIN LAWNS 

11 

Paul 

By 2/ 

H. Santelmann- 

Commonchickweed (Stelloria media L.) and henbit (~amplexicaule 

L.) are becoming major weed problems in Maryland lewns. In the 

early spring of 1957 and during the winter of 1957-53, various treatments 

were applied to a Kentucky Bluegrass lawn on the University of I 

Maryland campus in which these weeds were present. 

Materials 

and Methods 

One hundred square foot plots were treated on April 3, 1957 (date 1), 

December 23, 1957 (date 2), and March 3, 1958 (date 3). Where possible, 

treatments were made at the rates recommended on the container. Silvex 

(2,4,5 trichloropropionic acid) was used at \, 1 and 1\ pounds per acre. 

In the trial on date 3, samples of silvex from the Dow Chemical Company 

and AmchemProducts Inc., were compared. Other herbicides used were: 

2,4- dichlorophenoxybutyric acid (2,4-DB) at 1 and 2 pounds per acre; 

pctassium cyanate (KOCN)at 12 pounds per acre; disodium methyl arsonate 

(DSMA)as recommended on the container; neburon at 2 pounds per acre; 

isopropyl-N (3 chlorophenyl) carbamate (CIPC) at 1 and 2 pounds per acre, 

both in liquid and granular form; and dinitro orthosecondary butyl 

phenol (DNBP), amine salt, at 1 and 2 pounds per acre, both in liquid and 

granular ferm. 

The weeds were generally about 2 to 3" tall when treated, and all 

treatments were in 3 replications. Air temperature varied from 50 0 

to 60 0 F at the time of treatment. The treatment area was a well 

established Kentucky bluegrass lawn. In the case of date 3, a light 

rain began 15 minutes after the plots were treated. The silvex, CIPC 

and DNBPwer e applied with a hand sprayer, and the KOeN, neburon, and 

DSMAwith a sprinkling can. The granular materials ,"ere mixed with 

sand and applied by hand. 


Table 1 shows the degree of control that resulted from the various 

treatments. Neburon (2 lbs/A and 2,4-DB (1 & 2 lb/A) did not control 

the chickweed. The degree of control with the other herbicides varied. 

The granular materials were relatively ineffective. Uncertain coverage 

resulted from the hand spreading of the granulars and it is felt that 

this is part of the cause for their poor showing. KOCNand DSMAcaused 

some injury to the weeds, and silvex, CIPC and DNBPresulted in very 

good chickweed control. The high rates of silvex and DNBPcaused a 

slight turf burn, and KOCNcaused up to a 30% burn. However, the turf 

appeared to recover from all these treatments. None of the other 

treatments resulted in turf injury. In the instances where one chemical 

was used either early or late in the winter the time of treatment appeared 

1/ Miscellaneous Publication No. 339, Contribution No. 2975, of the 

Maryland Agricultural Experiment Station, Department of Agronomy. 

11 Assistant Professor, Department of Agronomy, Maryland Agricultural

161. 

to have little effect with regard to silvex, CIPC or DNBP. With KOCN 

and DSMA,better results were obtained with the early winter (December) 

treatment. Silvex, DNBPand KOCNwere most effective for the control 

of henbit. 

SUMMARY 

Chickweed and henbit control plots were treated in an established 

Kentucky bluegrass lawn during the winter and early spring of 1957 and 

1958. Treatments used were: Silvex~, 1 and 1% pounds per acre; 2,4-DB 

at 1 and 2 pounds per acre; KOCNat 12 pounds per acre; DSMAas recommended 

on the container; CIPC, liquid and granular, at 1 and 2 pounds 

per acre; and DNBP, liquid and granular, at 1 and 2 pounds per acre. 

Silvex was the most satisfactory herbicide used to control the chickweed 

but liquid CIPC and DNBPwere also satisfactory. The use of KOCN 

and DSMAwas less satisfactory. Granular DNBP, granular eIPe, Neburon 

and 2,4-DB were relatively unsatisfactory. Henbit was best controlled 

by silvex, DNBP, and KOCN,respectively. 

Table 1 Perc eut Control of Chickweed and Henbit in an Established 

Kentucky Bluegrass LalYnwith Various Herbicides. 

Ratings made in May. 

Treatment 

Rate 

(lbs/ A) 

Treated 

4/3/57 

Chick 

Heed 

Treated 

12/23/57 

Chick- 

Weed Henbit 

Treated 

3/3/58 

Chick- 

Heed Henbi t 

Silvex 

Silvex 

CIPC 

DNBP 

(Dow) 

(ACP) 

KOCN 

DSMA 

GL"an.DNBP 

Gran.CIPC 

Neburon 

2,4-DB 

~ 

1 

l~ 

l~ 

1 

2 

1 

2 

12 

1 

2 

1 

2 

1 

95 

70 

90 

80 

90 

90 

100 

70 

90 

80 

80 

60 

50 

10 

40 

20 

30 

40 

100 

20 

20 

o 

70 

60 

o 

10 

10 

o 

10 

83 

100 

100 

o 

25 

o 

o 

68 

100 

100 

o 

o 

o 

o 

Acknowledgement is made to AMCHEMProducts ,Inc.; The Dow Chemical 

Company; E. 1. Dupont de Nemours and Company; and to the Miller Chemical 

Company for supplying the chemicals used in these experiments.

162. 

Observations on Pre~emergence and Post-emergence Crabgrass ControL; 

on the Control of Veronica filiformis with Endothal; 

and on the Effectiveness of 2,4,5-TP in Controlling a Variety of Turf Weeds 

Robert G. Mower and John F. Cornman* 

During the lY58 season we have en~ged in a number of experiments in selective 

control of turf weeds. None of the trials on anyone phase is comprehensive 

enough for a separate paper, but the observations on a number of aspects of 

weed control seem worth recording for the information of other workers in 

this field of interest. . 

Observations will be reported on these SUbjects: 

A. Pre-emergence 

B. Post-emergence 

crabgrass 

crabgrass 

control 

control 

C. Continuing observations on the control of Veronica filiformis 

with endothal 

~. The effectiveness of 2,4,5-TP (Silvex) in the selective control of 

various turf weeds 

The crabgrass trials were at the Cornell Turf Research Plots at the Nassau 

County Park, East Hempstead, L.I. Here several acres of turf plots have 

recently been developed and the lY58 season was the first there for turf research 

work. The 2,4,5-TP trials were at the Cornell Turf Research Plots, 

Ithaca, and the Veronica observations were on various upstate NewYork lawns. 

A. Pre-emergence Crabgrass Control 

nne of the newer approaches to one of the most persistent turf weed problems 

in southeastern NewYork and on Long Island has been the use of pre-emergence 

control materials for crabgrass (Digitarie. isc~and"p.: sanguinalis)'. 

A series of demonstration plots was set up at the Cornell Turf Research 

Plots at Nassau County Park, East Hempstead, ~.I., to observe the effectiveness 

of the several materials now being promoted for pre-emergence crabgrass control. 

Two separate areas were used for this test. Area A, selected because of its 

reliability for crabgrass infestation, consisted primarily of a thin, neglected 

turf of native bentgrass, red fescue and sheep fescue. Individ~al plots measured 

30 feet by 10 feet and were separated by 2 foot check strips. 

Area B consisted of blocks of essentially pure stands of individual grasses of 

Illahee red fescue, Pennlawnred fescue, Merion Kentucky bluegrass, commercial 

Kentucky bluegrass, SeaSide creeping bent, and Penncross creeping bent. Plots 

measuring 6 feet wide ran across each of these individual grass plots. Two 

foot cheek strips were left between adJacent plots. 

* Turf Research Assistant and Professor of ornamental Hort1..culture. t"espe~tiYcly, 

Cornell University, Ithaca, N. Y.

Ared A, with the exception of one plot, was treated on April 25, 1958. Treatments 

were a~plied to Ared B on May 14, 1958, plus an additional one to Area 

A. Second applications of Alanap 1F and Crag Herbicide were made on June 20, 

195d. In each area supplementary fertilizer waS added to those plots in 

which the pre-emergence crabgrass control material did not have fertilizer 

incorporated. This was applied in an inorganic fertilizer at the rate of 

1 pound of nitrogen per 1,000 square feet. 

~he following pre-emergence crabgrass control materials were used. 

Ma.teridls 

1. "Al.anap IF'' - U. S. Rubber Co., Naugatuck Chemical Division 

Na.ugatuck, Conn. 

2. "Ortho Lawn Pep" - California Spray-Chemical Corp., Lucas and 

0rtho Way, Richmond, Calif. 

3. Chlordane (72% emulsifiable concentrate, 8#a.e./gal.) - Velsicol 

Chemical Corp., 330 East Grand Avenue, Chicago, Ill. 

4. Chlordane (5% granular) - Velsicol Chemical Corp., 330 Grand 

Avenue, Chicago, Ill. 

5. "PAX" - Kelly Western Seed, Division of Coop. Aseoc , , 580 West 

13th South, Salt Lake City, Utah. 

6. "Crag Herbicide" - Carbide and Carbon Chemical Co., 30 East 42nd 

St., New York 17, N. Y. 

The materials used, rates of application and the dates on which cr~bgrass control~ 

estimates and turf injury ratings were made are shown in Table 1. 

Under the conditions of our trials none of the pre-emergence control chemicals 

gave complete control of crabgrass. While a reduction in crabgrass was observed 

where either chlordane or "PAX" had been used, this reduction -(21 to 

31%) was not adequate to be considered a satisfactory control. Perhaps time 

of application has an important bearing on the results obtained with preemergence 

n~terials, thus accounting for the marked difference between our 

results and some of those reported elsewhere. 

No turf inJury was observed on any of the plots with the exception of "0rtho 

Lawn Pep" where the strip crossed the Illahee and Pennlawn red fescues in 

Area B. Increased growth, stimulated by the fertilizer material incorporated 

with the chemical, had increased the susceptibility of these plants to leaf 

spot (Helminthosporium dictyoides). No injury was visible with the same 

material on the bluegrass or bent areas. The comparable addition of fertilizer 

to areas treated with pre-emergence chemicals which did not have fertilizer 

incorporated in them did not show this type of injury, although severe 

outbreaks occurred later in the season on all of the fescue blocks. 

163. 

'--

164. 

B. Post-emergence Crabgrass Control 

While pre-emergence crabgrass control has been one approach to this important 

weed probl~a, the maJority of control still centers around the use of postemergence 

materials. 

A series of ~lots was set up at the Cornell Turf Research Plots at Nassau 

County Park, East Hem~stead, L.r., to observe the effectiveness of a number 

of the standard muterials and four experimental materials for post-emergence 


The area in which the trials were conducted was seeded to a mixture of 2/3 

creeping red fescue and 1/3 Kentucky bluegrass in November 1957. Germination 

from this dormant seeding was ra.ther poor, and a thin turf eXisted at the time 

of crabgrass seed germination this spring. This' thin turf permitted a rather 

heavy crabgrass infestation in the area. 

Plots measured 8 by 30 feet with a 4 foot check plot between. Sprays were 

applied with a small plot sprayer. Pressure was supplied by C02 at 30 psi to 

four fan type Tee Jet nozzles on a hand boom. Each, chemical was applied in 

water at the rate of 100 gallons to the acre except where the manufacturer's 

recommendations indicatedmare or less should be used. First applications were 

made on June 27, 

seedling stage. 

1958 when first 

Second and third 

crabgrass plants were in a late 

applications were made on July 

two-leaved 

7 and July 

21, respectively. 

The chemicals and formulations used were: 

Materials 

1. Disodium monomethylarsonate hexahydrate 30%tMethar 30") - VI. A. 

Cleary Corp., NewBrunswick, N. J. 

2. Disodium monomethylarsonate pentahydrate 75% ("Methar") - W. A. Cleary 

Corp., NewBrunswick, N; J. 

3. Disodium methylarsonate hexahydrate 2.5% (Weedone "Sodar") - American 

Chemical Paint Co., Ambler, Pa. 

4. Octyl ammoniummethylarsonate 8%and dodecyl ammoniummethylarsonate 8'fo 

("Artox Crabgrass Killer") - Nott Manufacturing Co., 

Mt. Vernon, N. Y. 

5. Potassium cyanate - American Cyanamid co . , NewYork 16, N. Y.) 

6. Phenyl mercuric acetate 2.510 ("pMAS") - W. A. Cleary Corp., 

NewBrunswick, N. J. 

7. Darmethene (Experimental) - W. A. Cleary Corp., NewBrunswick, N. J. 

8. Niagara 4562 (Experimental) - Niagara Chemical DivL;ion, Food 

Machinery and Chemical Corp., Middleport, N. Y. 

9. G-106 and G-110 (Experimental) 

Water St., Ossining, 

- Gallowhur 

N. Y. 

Chemical Corp., North 

10. U-9612 and U-9613 (Experimental) - Upjohn Co Research Division, 

301 Henrietta st., KD.J..nmztlo ,·'·M!ch.

165. 

As shown in Table 2, satisfactory crabgrass eontrol (90%+) WaS obtained with 

a number of the post-emergence chemicals. These included the disodium methylarsonate 

group, ammoniummetbyla:t'lilO%l.ateand phenyl mercuric acetate. 

In the disodiwn methylars~nate group no significant difference in crabgrass 

control WaSnoted between the liquid and powder formulations. Where the powder 

formulation was applied at double the recommended rate, excessive turf injury 

was noted so that after two applications a considerable portion of the desirable 

turf grasses·was killed; on these plots the third application was omitted. 

The ~rumonium methylarsonate gave a significantly greater degree of control 

following two applications of the chemical than did the disodium methylarspnate 

but there wa.s a co:rresponding increase in turf discoloration. Turf recovery 

from these applications was also quite slow. 

Potassiwn cyanate gave an intermediate degree of control. This is in line 

with the commonopinion that potassium cyanate is more effective on mature 

crabgrass than on seedlings. 

Phenyl mercuric acetate gave good control of crabgrass in the plot area but 

gave no control over another grassy weed, Panicum dichotomiflorum, present in 

the test area, so that from superficial observation it appeared. that no control 

of crabgrass had been obtained. The disodium and ammoniummethylarsonates 

controlled both the crabgrass and the Panicum equally well. 

Amongthe experimental materials, only Darmethene and Niagara 4562 at the 8 

pounds of active ingredient per acre rate gav.e any cO~l

166. 

b. Uniform coverage using a ~ressurized tank and fan-type nozzles is 

required forgond selective control. ' 

c. Best, results will be ona.rEji;loSmowed.recently to uniform height and, 

free of clippings and debris that might shield the Veronica. 

d. In addition to V. filiformis, endothal will control white clover (fa.ll 

and spring applications-only). Incidental observations, of other weed species 

of Veronic~ indicate that oontrol may also be expected of V. arvensis, V~ 

offic1nalis,. and, Y:.PE:rsica. There, has been no opportunity to observe effects 

on ~ serpyllifolh. 

e. Endothalwillnot control dandelions, plaintd.ins, etc. The 2,4-D susceptible 

weeds can be controlled by adding 2,4,"D at the usual rates to the 

endothal without modifying the potency or range' of either chemical. 

f. At the rec~nmended rate of endothal, bentgrass and Poa trivialis show 

the most inJ1ll'Y; with red fescue next and lCentuckybluegrasS"Teast. The bluegrasses 

.md bent recover rapidly tromendothal discoloration. Red fescue 

recovers more slowly, and may suffer some permanent damage. 

g. Normal endothal treatments will not iriterferewith the growth of,reseedingswith 

the comm6nnorthern grasses. Poa trivialis, Kentucky bluegr.J.ss', 

Merion Kentucky bluegrass, creeping red fescue, creeping bent, and 

domestic ryegrass d.llgerminated normally following surface soil treatments 

with endothal both Just prior to ~nd~immediatcly after seeding. 

D.The EffectiveneQs of 2,4,5-TPin Selective Control of Various Turf Weeds, 

The herbicide '2,4,5-TP C-2(2,4,5-trichlorophenoxy) propionic acid] has been reported 

by Gallagher and Jack* to be effective against two of the trOUblesome, 

low growing, mat-forming turf weeds, commonchickweed, Stellaria media, and 

mouse ear chickweed, Cerastium vulgatum. Its effectiveness against most other 

turf weeds has not been recorded. 

To observe the effectiveness of 2,4,5':TP on a variety of 'turf weeds, approxima.tely 

7500 square feet ot' turf consisting of a mixture of Kentucky bluegrass, 

red fescue, and creeping bentgrGss infested with a~ide variety and number of 

weeds was treated with 2,4,5 -TP in one -half of the area and a mixture of 

2,4,5-TP and 2,4-D in the other. .' 

In both cases, the 2,4,5-TP was applied at the rate of It pounds of active 

ingredient to the acre, while the 2,4-D was applied at the rate of 3/4 pound 

of active ingredient to the acre. Treatments were made in water at the rate 

of 50 gallons tO~fe acre on ~ctober 3, 1958. The herbicides were ~pplied 

with an exper1men~plot sprayer bearing a 9 foot bdomsupplied with 7 fan-type 

Tee Jet nozzles. Presscre was supplied by CO2at 30' pounds per square inch. 

Ten plants each of 16 different weeds were then marked for observation at D. 

later date. For such creeping weeds as clover and chickweed, ten areas of 

infestation were marked. Because of the retarding effects of cool weather and 

the late falla~plication, the degrees of control noted in these early obser- 

* Ga1l3gher, J. E. and C. C.Jack. Chickweed control test 1956-57. Proc. 

N.E. Weed Control Conf. 12: 151-153. 1958.

167. 

vdtions were recorded in thr~e categories: control, in which the treated plants 

h~ve been killedj promising, in which curling or yellowing have taken place but, 

at the time this paper w~s prepared, it was still not definite whether the 

plants will recoverj and no control, where no effects of the herbicide are 

evident. 

A summary of the observations is found in Table 4. Included in this 

table are a few observations from other trials, each explained in a footnote. 

Under the conditions of our trials, mouse ear chickweed, Cerastium vulgat.um, 

and commonchickweed, Stellaria media, were controlled by 2,4,5-TP:- 

A more rapid control was noted for Stellaria media, with all plants un~er observation 

completely dead two weeks after treatiiie'ilt. Effects on Cerastium 

vulgatum were much slower and not all plants were dead by the endOfafour 

week period. Stitcbwort, ?tellaria graminea, was also controlled. This weed 

is more commonthan is gener~lly recognized, especially in golf course fairways, 

but its fine texture, grass-like color, ani apparent lack of interference 

with plaY have kept it from being widely reeognized as an important turf 

weed. An increase in inquiries as to its identification and control 

have been noted in recent seasons. 

Observations on y~rrow} Achillea millefolium, indicate that it, to~, can 

be controlled. by the use of 2~5-TP. Applications of 2,4,5-TP at the rate 

of 1.5 pounds of active ingredient to the acre to a yarrow-infested lawn in 

Glen Cove, Long Island, in tbe fall of 1957 gave complete control that season 

and there h~s been no regrowth since that time. Two separate plots treated 

on the Cornell Ca~m9us in the spring of 1958 gave complete control of yarrow 

with no evidence of regrowth to date. Yarrow, up to this time, is one of the 

weeds for which there has been no good control. 

Apart from its value for the control of the chickweeds} 2,4,5-TP in our 

trials shows some possibilities for the control of a nt$ber of other turf 

weeds. This broader range of weed control would be of value in eliminating 

the need for additional chemicals to kill other turf weeds that might remain 

after the chickweeds had been removed. Early observations show that 2,4,5-TP 

may have value for the control of narrow- and broad-leaved plantains} dandelion, 

ox eye daisy, wild carrot and thistle. No conclusions on these items 

are justified at the present time, but observations will be continued. 

Ground ivy, Nepeta hederacea} self heal, Prunell~ vulgaris, and Veronica 

filiform1s were n~ntrolled in these trials by either 2,4,5-TP alone or 

in combination with 2,4-D. 

Summary 

1. Pre-emergence crabgrass control: under the conditions of these 

tritl.ls, none of the materials used prOVided adequate crabgrass control. "PAX" 

gave 31% control and chlordane at 60#/A gave less than 25% control. Alanap IF, 

Crag Herbicide #1, and Ortho Lawn Pep were ineffective. 

2. Post-emergence crabgrass control: Disodium methylarscnate, ammonium 

methylarsonate, and PMAgave good crabgrass control (90% +). Potassium cyanate 

was less effective (65%). Darmetijene, Niagara 4562, G106, GllO, U-9612, and 

U-9613 either produced intolerable turf injury or very little crabgrass control. 

The arsonate compounds also controlled Fanicum dichotomiflcrum and are 

thus to be preferred to PMAwhere Panicum is also a problem.

168. 

3. For selective control of Veronica filiformis, two successive treatments 

with endothal at the rate or--l# actual endothal in 100 gallons of water 

continues to give excellent results. 

4. 2,4,5-TP ut l~/A controlled mouse-ear chickweed (Cerastium vulgatum), 

commonchickweed (Stellaria media), stitchwort (S. graminea), and white clover. 

A~pdrently 2,4,5-TP was also~ctive against y~row (Achillea) and yellow 

rocket (Barbarea). Results against a number of other weeds were apparently 

less s~tisfactory. 

i';'-' 

Table l. Pre-emergence crabgrass control·trials 

Area A - treated April 25, 19$8. Plots 10 x 30 feet, unrtJplicated. 

Area B - treated May 14, 1958~ Plots 6 x 90 feet, unreplicated. 

Loc..tion - Turf Research Plots at Nassau County Park, East Hempstead. 

Area A 

Area B 

%crabgrass Turf 1>crabgrass Turf 

centrol izjUrl. control inJury 

t.eri.ll Ro.te/M* mO §lli 7 10 @ M:i tm: 

Alanap lF 18# 0 0 0 0 0 0 

Chlordane 

510granular 30# 38 27 0 29 23 0 

Chlord~ne 

72%emul. 24 oz. 31 26 0 26 2l 0 

Crag Herb. 

No. 1 10 tbl. 0 0 0 0 0 0 

Ortho Lawn 

Pep 20# 0 0 0 0 0 3·0** 

PAX 25# 20 23 0 33 31 0 

Turf Injury Rutings: 0 - none; 1 - light; 2 - moderate; 3 - severe; 

4 - complete kill. 

* Rates are label or m4nufacturer's recommenddtions. 

** Injury evident only on Illahee and Pannlawn red fescue.

169. 

Table 2. Post-emergence crabgrass.control 

Tre~ted June 27, July 7, and JUly 21, 1956 

Plots 8 x 30 feet, unreplicated. 

Turf 

Percent c~rass control discoloration 

71 ?M 

.Mdt er LJ.l. ~ ill ill WE lli 

l.'DSMA - liquid 8 oz/M 28 67 95 1.5 1.5 1.0 

za: DSMA- powder 4 oz/M 30 68 93 1.5 1.5 1.0 

2b. DSMA- powder* 8oz/M 33 76 97 3·0 3·0 3·5 

3· DSMA- granular 6#/M 10 36 68 1.0 0·5 1.0 

4. ANA - liquid 10 oz/M 37 85 91 2.5 2.0 2.0 

5· KoeN l2#/A 12 43 65 3·0 2.0 2.0 

6. PMAS 3 oz/M 8 67 97-Ydf 1.5 2.0 1.5 

7· Do.rmethene 2 oz/M 33 56 90 2.5 3·0 3·0 

8~. Niago.n 4562 4#/A 10 lb 23 2.0 1.5 1.0 

Bb, Niagara 4562* 8#/A 18 30 80 2·5 3·5 3.5 

90.· G-106 til/A 0 5 5 0.0 0·5 0.5 

9b. G-110 til/A 0 5 5 0.0 0.5 0.0 

100.. U-96l2 5 gal. of 

6000 ppm/M 12 5 5 1.0 0·5 0·5 

lOb. U-:;I613 5 gal. of 

6000.ppm/M 10 5 5 0·5 0·5 0·5 

% crabgrass in checks 87 85 90 

LSD 5% 9.... 7 6 

1% 13 10 9 

Turf discoloration ratings: o - none; 1 • slight; 2 - moderat.e ; 3 - severe; 

4 - complete kill. 

Percent crabgrass control cuLcul.at.ed on basis of percent crabgrass in checks 

at the time of estimating. 

* Two applications only; turf injury too severe to permit d third application. 

** Excellent control of crabgrass but no control of Panicum dichotomiflorum 

~lso found in this plot.

170. 

T.lble 3. Veronic..l filifon',l1s ~ont:'ol on Lwn turf with endcxha.L, 

First application July 10, 1957 

Second applic~tion September 23, 1:;157 

Plots 4 x 25 feet, oomplete randomized block in 

triplicate 

Pound::; Per cent Veronica control 

actu.J.l Gallons Time after first treatment 

er.dothal!A per acre 5 days if mos. 4!mos. 11 mos. 15 mos. 

1 

2" 

25 30 43 71 68 71 

50 45 70 83 79 d3 

100 75 63 85 83 75 

1 25 71 71 7'3 75 70 

50 68 80 8:; 8tl 88 

100 83 85 99 92 93 

2 25 58 68 ;/1 89 90 

50 80 70 Y9 :;18 98 

100 88 88 99 98 98 

LSD ':lfo 15 12 ';) » 7 

1'/0 21 16 13 13 10 

'fo Veronica in check 75 70 72 80 80 

'fo Veronic~ control calculated on the basis of aver~ge ,unount present in 

each plot prior to treatment.

Table 4. Observ ..tions on weed control in turf using 2,4,5-TP and 

2,4,5-TP + 2,4-D combination 

Tre~tmento applied October 3, 1~58 unless otherwise indic~ted 

Observations on 10 marked plants or areas of infestation 

.nade on November 5, 1958 

Number of plants or areas observed 

171. 

..Je"d sj,lecies 

Achillea 

millefolium 

Y:'.rrow 

Barb~rea vulg~ris 

Y",llow Rocket 

Cerastium vulgatum 

Mouse~r Chickweed 

Cirsium sp. 

Thistle 

Chrysanthemum leuc~nthemum 

Ox"'eye Daisy 

Daucus c:J.rota. 

Wild Carrot 

Dipsacus sylvestris 

Teasel 

Ncgeta hederaceae 

Ground Ivy 

P~lntago lanceolata 

Narrow Leaved Plantain 

P'lnnt.ago =Jor 

Broad Leaved Pl~ntdin 

Prunella vulgaris 

S"lf He:J.l 

Rumex crispus 

Curly Dock 

3tl.lll~ri~ graminea 

Stitchwort 

Stellaril medf.a 

CommonChickweed 

Tarlxacum officinale 

Dande Lf.on 

Trifolium rapens 

White Clover 

Veronica drvensis 

Veronica filiformis 

Veronica, serpyllifol:!.,l ' 

Thyme-leuved Speedwel~ 

3* 

10 

7 

1 

4 

1 

1 

6 

10 

1 

10 

1 

1: 

3 

8 

9 

6 

8 

8 

7 

4 

8 

5 

4 

1 

1 

1 

10 

2 

2 

10 

1 

4 

3*** 

5 

3 

4 

5 

'7 

8 

7 

10 

10 

2 

3 

7 

6 

5 

3 

3 

2 

3 

3 

1 

6 

4 

7 

1 

2 

3 

* Achillea millefolium control observed on a Long Island home luWDone 

year after treatment and on two areas on the Cornell Cmnpus grOunds 

six months after treatment. 

** Stellaria gramine:J. control noted in trials on Cornell University Golf

172. 

VEGETATIVECONTROLOF WEEDSONHIGrrwAYSLOPES 

Fred V. Grau* 

Paper prepared for presentation before k959 

N.E. Weed Control Conference, New York City 

C In this paper we make no pret~se of presenting research 

data. Rather we shallma~~.simple statements of accomplished 

facts in practical usage 'd ••'rne vegetation to which we refer in 

the title, which is so effective 1n controlling weeds on highway 

and other slopes,is Cr~ Vetch, Coronilla varia. The variety 

which has been res~oreible for the accomplishments is PENNGIFT. 

All slnpes present certain difficulties in maintenance. 

They are more expensive to maintain than level areas. As runoff 

increases the slopes become more arid. Fertility, low in slope 

subsoils at best, rapidly decreases by various well-known means. 

Most slope mistures require periodic maintenance fertilization 

to provide continuously-satisfactory cover. Weeds that inevitably 

occur either must be mowed or sprayed. Either method, 

entails extra cost which depletes maintenance funds. Mowing 

of slopes may start erosion where vegetation is disturbed by 

equipment which creates ruts when slipping and sliding.. Fatal 

accidents have occurred when equipment has overturned on steep 

uneven 'terrains. Spraying reduces hazards to life· and property 

when equipment is kept on the berm. It, too, costs money for 

machinery, materials and technical skills which affect maintenance 

budgets. One of the evils of chemical sprays, to many, is 

the wholesale and unwarranted destruction of beautiful native· 

wild flowers which add charm and grace to otherwise dreary 

monot0nous expanses of grass. 

. It has been the privilege of the author to have been 

~ntimately associated with crown vetch since 1935. ~n that 

year we saw steep slopes (1:1» that had been protected for many 

years with this spreading perennial legume. These same slopes 

ar~ still covered today without the expenditure of a penny for 

ma~ntenance. The high degree of freedom from weeds has been an 

outstanding char~cteristic. 

Beginning in 1947, when a limited quantity of crown vetch 

seed was produced in Centre County, Pennsylvania, the Pennsylvan~a 

Department of Highways established doze~s of demonstration plant~ngs 

of crown vetch on various soils in different parts of the state. 

Now, 10 years and more later, with no expenditure for maintenance 

of any kind 

i 

these areas pre sent a solid cover of, crown vetch 

with virtua ly no weeds. Some of the test 'sites, to name only a 

few, may be found on U.S. 22 at intervals between Pittsburgh and 

Allentown; on U.S. 422 near ButJp.r and Newcastle; on slopes near 

Wellsboro, Tunkhannock and Factoryville, and in the southeast ~ 

near Westchester. There are many more.

Experimental work begun in 1947, conducted by the Pennsylvania 

State University in cooperation with the Pennsylvania Department of 

Highways, has continued to date and has provided valuable data on 

establishment and competition. The first set of plots was destroyed 

in a road widening project. The second' set established in 1952 has' 

been reported in Science For the Farmer, Vol. V, No.4, Spring 195$, 

and continues to provide useful information. A significant portion 

of the summary from this report is, "At the end of the sixth season 

(1957) crown vetch was still providing complete slope protection 

without additional fertilization or other maintenance treatments". 

Now it is at the end of the seventh season and the slope still is 

perfectly covered and almost weed free. 

Several state highway departments have recognized the ability 

of crown vetch to control weeds and to reduce maintenance costs. 

Accelerated planting programs are under way in Pennsylvania, New 

Jersey, Indiana, and Kansas, to name only a few. To date there has 

been no report of crown vetch becoming a nuisance like honeysuckle 

and kudzu vine. 

173. 

It seems pertinent to suggest ways in which crown vetch controls 

weeds. It st ar-t e " growth very early in the spring thus getting a head 

start on other vegetation. It has been shown to be highly competitive 

and able to rise above most other plants. There is green growth even 

during periods of drought which turns most plants brown and dry. Its 

ability to grow well in almost any type of soil or subsoil gives it 

an advantage possessed by few other plants. The extensive fibrous and 

rhizomatous underground system enables crown vetch to occupy areas 

continuously and aggressively to the detriment of other vegetation. 

It is suspected that the nitrogcln gathered by the associated bacteria 

may have an effect on weeds that try to compete. The soil becomes 

covered with a dense mat of leaves and stems which effectively seem 

to insulate seeds from the soil and which smothers any seedlings that 

start. The heavy shade of a dense cover of crwwn vetch is discouraging 

to all but the most shade tolerant species. 

Regardless of the mechanisms by which weed control is accomplished 

by crown vetch, it remains a fact that, to our knowledge, every undisturbed 

planting on slopes has remained weed-free throughout its life 

thus far, without a cent of cost .for maintenance. A Pennsylvania 

District Roadside Engineer who has used crown vetch on all major 

slope projects made the statement recently that, "I have never seen 

a crown vetch planting go backwards". 

It· would seem folly to exper-t anything more of a plant that controls 

erosion, chokes weeds and provides zero maintenance. But·the crowning 

attribute of crown-vetch, over andIDove its Utility value, lies in the 

Beauty of the rose, pink and white blossoms which occur in great masses 

over a long petiod of the growing season. The attractive scene pre- 

'- sented to the traYeler is ~ufficiently varied so that the stigma 

of monotony is avoided.

174. 

The Kodachrome slides which are a part of this paper prewant 

visual proof that weeds are controlled by a solid cover of crown 

vetch under a system of zero maintenance. To date there have been 

no complaints of nuisance from adjoining property owners. Based 

on data and observations accumulated over a period of nearly 25 

years, the conclusion may be drawn that th~ establishment of 

crown vetch offers a desirable, economical, low-cost vegetativee 

method of controlling weeds on- highway and other slopes.

175. 

Combinations of Chemicals for Weed Control in 

NewAlfalfa Seedings 

1 

Robert A. Peters and Albert J. Kerkin 

Significant progress has been made of late in obtaining weed control in 

new seedings of forage legumes. Particular interest has been placed on 4, 

(2,4-DB) for the control of broadleaf weeds and on dalapon for the control of 

grassy weeds. A logical sequence has been to combine the two chemicals in 

one treatment to give control of both types of weeds usually found in new 

seedings. 

Neburon has given good broadleaf weed control in some experiments both 

as a pre-emergence and post-emergence herbicide (2,3,4). Neburon has generally 

been more effective on broadleaf weeds than on grassy weeds. Adding an 

herbicide in mixture which is effective on grassy weeds should be investigated. 

Procedure: 

The experiment was conducted at the University of Connecticut Agronomy 

Research Farm, Storrs, Connecticut. The experimental design was a randomized 

block replicated three times with the individual plots measuring 6 by 12 feet. 

The seeding was made on May23, 1958 by banding alfalfa - smooth bromegrass 

with a grain drill at 12 pounds and 6 pounds per acre, respectively. 

The chemicals were applied on June 13, 19S5. The prevalent species present 

at the time of spraying and their stages of growth were as follows: 

Alfalfa - 1st true leaf stage, a few in the 2nd true leaf stage. 

Bromegrass - emerging. 

Mustard - 2-3 inches tall and 3-6 inches in diameter. 

Also present were commonchickweed (Stellaria media),White cockle (Lychnis 

alba), yellovl foxtail (Setaria lutescens), and lesser amounts of ragweed (Ambrosia 

artemisifolia), and lambsquarter (Chenipodium album). Rainfall during 

the entire 1958 growing season was 'more than ample and vleed growth was unusually 

profuse. Grass growth in.particular was unusually heaV'J. 

Chemioal Treatments: 

All rates are given in tenus of pounds acid equivalent or active ingred 

per acre: 

ients 

1 Associate Agronomist and former Research Assistant, University of Connecticut, 


176. 

1. No chemical 

2. No chemical - Handweeded June 16 and July 11, 1958. 

3. Neburon 4 plus Dalapon i. 

4. Neburon 4 plus Dalapon 1. 

5. 4(2,~DB) 2 plus Dalapon 1. 

6. 4(2,4-DB) t. 

7. 4(2,4- DB) ' . 

The treatments were applied With a bicycle type compressed air sprayer 

using 40 gallons of solution per acre. 

Results: 

The treatment effects were based on yields of hand separated components 

of the samples cut from each plot on August 13, 1958. The yield data are 

given in Table I. The bromegrass stand was so weak at the time of harvest 

that no attempt was made to determine yields. 

TABLEI 

Yields of Alfalfa and Weed Components of New 

Seedings Two Months Following Treatment 

Treatment 

Alfalfa 

Yields in Pounds Pe::'~Ac~r...e,,--,:,:",:-:," __ 

Grassy Broadl;af White 

weeds weeds cockle 

Check 644 956 2998 402 

Handweeded check 2202 272 112 0 

Neb 4 +Dal ! 1518 1455 514 0 

Neb 4 + Dal 1 2206 476 268 0 

2;4-DB 2 + DSl 1 666 1410 1053 260 

214-: D ! 22'7 2236 435 372 

2,4- D 2 . 100 1923 324 339 

The broadleaf component included considerable commonchickweed \'Jhich was 

not separated out. It was obvious, however, from notes made during the progress 

of the experiment that the chickweed was controlled on those plots 

treated with neburon , The control of \'Jhite cockle by neburon was also quite 

evident. It was assumed that the neburon rather than the dalapon component 

of the chemical mixture 1rlasthe active agent since neither chickweed or white 

cockle was controlled by the dalapon - 2,4-DB IlIixture. This is in 'contrast 

to a report by Churchill (1) but the cockle was treated at a much younger 

stage in this experiment. Excellent control of mustard from neburon as previously 

found was again evideni. in this experiment (3). Since neburon in a

177. 

previous experiment showed limited toxicity on grasses, the adequate grass 

control obtained in this experiment, when combined ldth the one pound rate 

of dalapon, would indicate more than an additive effect. 

The weed control obtained trom the 2,4-DB - Dalapon combination "TaS not 

as satisfactory as those reported in a previous experiment and no increase 

in alfalfa yield was obtained (3). This can be related to poor grass control 

obtained with the one pound rate of dalapon unier the conditions of this experiment. 

This is attributed in part to the frequency of barnyard grass in 

the stand which is not controlled by the lower rates of dalaponoand in part 

by the unusually favorable conditions for grass growth during 1958. The low· 

yields of alfalfa following the use of 2,4-D can be explained in part by 

direct chemical toxicity and in part by the increased competition of the 

grassy weeds released from the competition of the broadleaf weedS killed by 

the 2,4-D. 

SUJIlIIIIl.ry: 

The experimental evidence given in this paper indicates that a neburondalapon 

combination is promising for early post-emergence weed control in pure 

stand alfalfa. This treatment gave both grassy and broodleaf .weed control including 

the control of both commonchickweed am white cockle. Both of these 

species are only slightly effected by 2,4-D or 2,4-DB at rates usually used. 

The data given again shows the feasibility of obtaining 1 ton yields of 

alfalfa within two months of the time of seeding. 

Literature 

Cited 

1. Churchill, B. R. Annual Weed Control in New 8eedings of Birdsfoot Trefoil 

and Alfalfa-Red Clover Mixture. 14th NCWCCRes. Rept , , p. 100. 

1958. 

Z. Hull, R. J. and Wakefield, R. C. The Effect of Selected Herbicides - Alone 

and in Combination - on the Establishment of Legume Seedings. Proc, 

12th NEWCC,pp, 168-176., ;1958. 

3. Kerkin,~~J. and Peters, R;'·::A·~ . Herbicidal Effectiveness of 2,4-DB, MCPB, 

Neburon and Other Materials as Measured by Weed Control and Yields of 

Seedling Alfalfa and Birdsfoot Trefoil. Proc. 11th NEWCC,pp. 128-138. 

1957. 

4. Kerkin,. A. J. and Peters, R. A. Effect of Herbicidal Treatment on the 

Winter Heaving of Late SUlIDl1erSeeded Alfalfa. Proc , 15th NEWCC,pp, 

159-166. 1958. 

Acknowledgement is made to the t.:ollowing companies for supplying the chemiC'all'1 

used in" the above experiment: DowChemical Company? American Chemical Paint 

"Company, and E. I. Dupont de Nemours and Qompany. 

'.

.. 

A Comparison of Pre- and Post-Emergence Herbicidal 

for the Establishment of Legume Seedingsl 

R. J. Hull and R. C. Wakefield 2 

Trelatments 

Introduotign 

The recent development of highly selective herbicides has offered 

considerable promise in the establishment of forage seedings" 

Research conducted in the Northeast (3,4,5,8,9) has demonstrated 

that certain post-emergence chemicals can effectively con~ol the 

major annual weeds normally encountered in forage seedings, without 

seriously injuring legumes. 

More recent work (3) has shown that certain chemicals applied 

as a pre-emergence spray can give more immediate weed control with 

almost no injury to alfalfa or birdsfoot trefoil. 

Procedure 

To further evaluate the effectiveness of certain post-emergence 

chemicals and to compare these with pre-emergence treatments 

a test was established on May 14, 1958 on the Agronomy Research 

Farm. 

A split plot design was used with alfalfa (Narragansett - 10 

Ibs./A)and birdsfoot trefoil (Viking - 5 Ibs./A) as the main 

plots. Post- and pre-emergence herbicidal treatments were randomized 

Within each main plot. Four replications were used With individual 

plot size being 6 x 16 feet. 

In an effort to reduce variability in the weed population a 

mixture of weed seed was sown over the area. Foxtail millet (~etaria 

italica) was used as the annual weedy grass. Also seeded 

'W'8r8'"liiiibS'Q:uarters. (Chenopodium aloum), pigweed (Amaran~ W!:2 

~.!), white cockle (Lfchnis alba), wild radish (Raphanus 

raphanistrum) smartweed Polygonum oennsylvanicum) and wild mustard 

(Brassica keber The,a seeds had been harvested the previous 

year and treatea-tObreak dormancy according to methods described 

by Steinbauer and Grigsby (7). 

These weeds constituted 75% of the reSUlting weed population 

according to the following percentages of total number of weed 

plants present: 

Grasses 

Lambsquarters 

Pigweed 

- - - -- -- 

41.2 percent 

21~6 1\ 

6.4 It 

lContribution No. 963 R.I. Agricultural Experiment Station, Klngs-

Smartweed 

White Cockle 

Mustard and Wild 

Others 

Radish 

percent 

II 

.It 

.11 

179. 

The other weeds were mostly chickweed (Stellaria media), wood sorrel 

(Oxalis stricta) and purslane (Portulaca sp.):---- " 

Chemicals were applied in 30 gallons of water per "acre with a 

sprayer similar to that described by Shaw (6). Chemicals and . 

rates used were as followsl 

Pre-eme rgence I 

1. Ethyl n,n-di-n-prop~~1plcarbamate (EPTC) 6 lbs. A.E./gal.; 4 

and 8 lbs. acid equivalent per acre. . 

2. 3-(3",4-dichlorophenyl-l-methyl-l-n-butylurea), (Neburon), 

l8.5~ active; 2 and 4 lbs. active material per acre. 

4. 

Post-emergence: 

2,2-dichloropropioni¢ acid, sodium salt 74% A.E. (Dalapon); 2 

and 4 lbs. acid equivalent per acre. . 

4(2,4-dichlorOPhenOXY)butric acid, dimethyl-amine salt, 2 

lbs. A.E./gal. (2,4-D1~); land 3 lbs. acid equivalent per 

acre. 

5. D1nitro-O-sec-Butyl-phenol, alkanalamine salt,:3 Ibs. A.E./ 

gal. (DNBP); 3/4 and li lbs. acid .equivalent per acre. 

2-methyl-4-chlorophenoxyacetic acid,4lbs. A.E./gal. (MCPA); 

1/8 and 1/4 lbs. acid equivalent per acre. 

The time of app11cat1onof herbicides and stages of plant development 

were as follows: 

a. Pre-emergence - May 19 

Legume species - non appearing 

Broadleafweeds - germinating 

Grass - non appearing . 

b. .Post-emergence - June 17 

Legumes species 3-4 true leaf stage 

Weeds 2-3 inches high 

c. Post-emergence following pre-emergence - July 1 

Alfalfa - 8-10 inches 

Birdsfoot trefoil - 5-6 inches 

Grass weeds - 10-12 inches 

Broadleaf weeds - variable some flowering

180. 

The weather at time of pre-emergence spraying was cloudy, 

warm and humid. The soil was for the most part moist with some 

areas being considerably d~ier. 

At the time of post-emergence spraying the weather was cool 

and clear; the soil being moderately dry. Two days following 

treatment .Z~ inches of rain fell. On JUly 1, the time of the 

follow-up post emergence treatment, the weather was hot and humid 

with showers occurring in two days. 

In order to evaluate the effect of competing plant populations 

on legumes and establishment, three handweeded check treatments 

were maintained in addition to an unweeded check and a 

plot in which oats had been seeded. These check treatments consisted 

of (1) broadleaf weeds remo\ed (2) grass weeds removed 

and (3) all weeds removed. Plots were handweeded at the time of 

first post-emergence spray applications. 

The rainfall over the growing season of April through September 

was 10.63 inches in excess of the long term average. Much 

of the excess came during the months of July and August. This 

abundant moisture may have favored the activity of Neburon by 

washing it into the root zone thereby giVing much longer lasting 

effectiveness than was noted during the dry 1957 season (2) (3). 

The extremely moist conditions also tended to favor trefoil growth 

and development but did not appear to be optimum for alfalfa. 

All plots were rated for herbicidal effectiveness and injury 

to legumes at various intervals throughout the season. Stand 

counts were made using a 2-square foot quadrat at two locations 

in each plot two weeks following harvest. 

Alfalfa plots were harvested on July 31 and October 9. 

Birdsfoot trefoil was harvested once on August 12. A 38-inch by 

l4-foot strip was removed from each plot and the green weight determined. 

Dry matter samples were taken from each plot. Botanical 

composition was estimated and checked by occasional hand 

separations. 

Plant samples for crown and root observations were dug from 

I-square foot areas in each plot on November 5. Tillers per 

plant were determined for alfalfa and average dry weight per root 

\clipped to six inches) was determined for both alfalfa gnd trefoil. 

Pre-emergence: 

Results 

Initial 


Observations 

Observations following pre-emergence treatments indicated no

si , 

at the 4 or 8 lb. rates. Neburon, which showing no injury to alfalfa, 

did noticeably stunt birdsfoot trefoil particularly at the 

4 lb. rate. 

Both chemicals gave gead control of grass weeds. EPTC,however, 

did not give as consistent control of the broad leaved weeds 

as did Neburon. 

Later observations showed that EPTC did not have the residual 

properties of Neburon with many of the plots becoming heavily in-' 

fested with broadleaved weeds. 

Post-emergence 

a 

Observations on injury made at several dates after spraying 

showed that no chemical applied singly appeared to cause any serious 

injury to alfalfa o Alfalfa was retarded bI some of the combinations. 

Dalapon at 4 Ibs. per acre with MCP or 2,4~DB 

resulted in prolonged injury. Dalapon with DNBPgave only temporary 

injury of little consequence. Birdsfoot trefoil appeared less 

seriously injured by the combined treatments than the alfalfa.' 

The combinations of Dalapon and MCPAor 2,4-DB did not injure 

trefoil to the same extent that it did alfalfa. 

DNBPkilled mustard plants within 3 days of applIcation. 

Pigweed and lambsquarters were controlled most effectively by 

2,4-DB. Smartweed and white cockle appeared somewhat tolerant 

of all "post-emergence chemicals tested. Although requiring 

two to three weeks to act, Dalapon at 2 Ibs./A effectively controlled 

all grass species present. 

The mixture of Dalapon and 2,4-DB applied following a preemergence 

treatment effectlvely controlled all remaining weeds 

present but again showed injury on alfalfa. 

Effect 

on Yields 

Yields of alfalfa, birdsfoot trefoil, broad leaved and grass 

weeds are presented in table I. 

Alfalfa: 

Over one ton of alfalfa Was obtained from those plots receiving 

the pre-emergence Neburon treatments. This constituted 

a highly significant increase over both the unweeded and handweeded 

checks. Although this treatment resulted in relatively 

weed-free alfalfa, afollo~-up treatment with Dalapon plus 2,4 

DB gaye best results. 'Dal~pon at 2 Ibs. plus 2,4-DB at l~ lbs. 

gave yields oi:weed free forage in significant excess over the 

unweeded check.'

lS2. 

Table 1. Yields of legumes and .weeds following herbicide treatment. 

- - - - - - - -- - - - - - - - -YIerds-foOs-Ory-MatterP§lr Acte- 

. Lbs/A Birdsfoot Grass Broadleaf 

Ir~a~~ni ______ Baie __ Alfalf.a __ T!:ef.o!,l__ W§.eg,s __ \1e~d2. _ 

P T-EMERGENCE 

~ 

Oalapori 2 .72 .32 .00* .59* 

Oalapon 4 .57 .30 .00 .51 

2,4-0B l~ .49 .24 .44 .04 

2,4...oB 3 .62 .26 .51 .02 

ON3P ~ .70 .25 .58 .17 

ONBP 1~ .66 .36 .61 .12 

MCPA 1/8 .51 .29 .59 .12 

MCPA 1/4 .48 .32 .48 .10 

Dal. + 2,4-DB 2+1~ .80 .46 .00 .12 

Dal. + 2,4-0B 2+3 .69 .58 .01 .09 

Oal. + ONBP 2+:11 .70 .54 .04 .• 29 

Dal. + DNBP 2+l~ .84 .34 .00 .21 

Oal. + 2,4-DB 4+1l!! .48 .39 .01 .10 

Dal. + 2,4-0B 4+3 .55 .48 .00 .09 

Dal. + DNBP 4+~ .72 .62 .00 .24 

Oal. + ONBP 4+l~ .74 .38 .00 .15 

nai , + MCPA .4+1/8 .50 .38 .00 .29 

Q.al._+J\1£ P tl _ ~ 1+~ .12 .~8 ...OQ. .~l__ 

PRE-EMERGENvE 

Neburon 2 1. 08 .72 .25 .12 

Neburon 4 1.13 .82 .07 .05 

EPTC 4.64 .33 .11 .75 

5.PIC~ .... §. _ 7i __ .27__ ~ _.2 3 ...01 .19_ :'\ 

PnE ANDPOSt-EMERGENCE \Oal. 4+2,4-uB l~, 43 days after pre-eml 

Neburon 

Neburon 

2 

4 

~84 

1.04 

EPTC 4 .42 .52 .00 .14 

gPI~ECK-TREATMENTS - §. - - - _.14 __ - _.~7 .LO~ .1.7__ 

.71 

.72 

.01 

.00 

Oats .46 .22 1.03** .19 

Unweeded .48 .23 .60 .41 

Grass Removed .62 .28 .04 .74 

Broadleaf Weeds Rem. .51 .31 .67 .01 

All Weeds Removed .80 1.03 .01 .08 

LSD(p = .05) .27 .25 .13 .16

treatment t however, was able to equal. the yield. ·Ob.tained ...from the 

handweedea ch&ck. Da'Laporr combln&d with 2~4.-DB (at 3 lb.) or 

DNBP.(at 3/4 lb.) resulted in yields significantly greater than 

the unweeded check. 

Yields of grass-type and broadleaf weed~: 

As shown in table 1, all treatments fuvolving Dalapon sign1ficant~y 

controlled grass weeds. Neburon gave good grass control, 

particularly at 4 Ibs./A. EPTC was effectIve at both 4 and 8 

Ibs./A. 

The most consistent broadleaf weed control was obtained from 

2,4-DB and Neburon alt~ough both MCPAandDNBP also significantly 

reduced weed yields below that of the unweeded check. EPTC proved 

quite erratic. in its effectiveness against broadleaf weeds and resulted 

in weed yields comparable to those of theoheok from which 

all grass had been handweeded. The reduced broadleaf weed yields 

of both the oats and unweeded checks show the influence of heavy 

grass stands in suppressing the growth of other weeds. The reduced 

yields of legume from these plots could be attributed to 

the same factor of excessive grass competition. 

Plant 

Counts 

Data on stand counts, expressed as piants pe~ square foot, 

will be found in table II. 

Alfalfa: 

Pre-emergence applications of Neburon with or without atollOW-Up 

treatment resulted in a highly significant increase in 

stand. This was probably due to effective control of weeds at 

emergence. Seedling weeds although controlled post-emergence by 

several chemicals apparently resulted in stand suppression. Similarly 

the check plots, har.dweeded at time pf post-emerge~ce 

spraying failed to main tail. a stand comparable to the Neburon 

plots. Effective weed control during the first month of legume 

establishment would seem to be important from the results obtained 

in this experiment. 

Birdsfoottrefoil: 

No treatment gave a significant increase in legume stand over 

the unweeded check. This was undoubtedly due to excellent growing 

conditions during the 1958 season. As was indicated in the Initial 

Observations, Neburon, particularly at the 4 lb. rat·e, significantly 

reduced trefoil stands below that of the check plots. 

~oot 

Data 

Rnnt mAABu~ementB taken from one sauare foot per plot are

LSD (p = .05) 4.6 N.S. .17 3.4 .38 

Table 2. Stand counts 

foot trefoil 

and root 

following 

measurements of alfalfa 

herbicide treatments. 

and birds 

- - - - - - - - - - - - - -- - -A!falfa- - - - - - -BIrdsfoot-Trefoil 

Lbs/A Plants Tillers Root Wt. Plants Root Wt. 

Ir£.atm~nt ___ fiate_ ..I~q..fi •..I!?ls.ni - Lf~:;:T - ..I~q..fi •..If~;~~)- 

POST-EMERGENCE 

Dalapon 2 23.0 5.2 .37 17 .5 .59 

Dalapon 4 22.9 5.3 .40 19.2 .67 

2,4-DB 

2,4-DB 

112 

3 

21.2 

23.6 

4.7 

5.0 

.41 

.42 

17.4 

20.0 

.60 

.73 

DNBP 

D1'I3P 

~ 

112 

26.2 

22.1 

4.9 

5.3 

.38 

.52 

17 .0 

18.6 

.72 

.73 

MCPA 

MCPA 

1/8 

1/4 

18.6 

19.2 

4.6 

4.7 

.34 

.36 

19.7 

18.4 

.65 

.63 

Dal. 

Dal. 

+ 2,4-D8 

+ 2,4-D8 

2+112 

2+3 

24.1 

22.8 

4.8 

5.0 

.42 

.46 

18.0 

19.2 

.84 

.79 

Dal. + DNBP 2+~ 

Dal. + DNBP 2+1~ 

23.1 

22.2 

4.5 

5.8 

.36 

.52 

19.0 

17 .0 

.61 

.51 

Dal. 

Dal. 

+ 2,4-D8 

+ 2,4-D8 

4+1Y2 

4+3 

23.2 

21.0 

5.0 

5.3 

.35 

.43 

18.3 

20.8 

.90 

.68 

Da1. + DNBP 4+~ 

Dal. + DNBP 4+1~ 

23.6 

24,4 

4.7 

5.3 

.38 

.40 

15.0 

17.2 

.98 

.99 

Dal. + MCPA 4+1/8 22.7 

Qalp~:~~~GENCE1+~ - - ~1..4__ 

5.6 

1.a 

.48 

...3~ 

17.2 

16.:.5 

.54 

.28__ 

Neburon 

Neburon 

2 

4 

26.1 

27.8 

6.1 

5.3 

.59 

.43 

15.0 

8.6 

1.04 

1.77 

EPTC 4 22.8 5.7 .49 19.0 

liPIC ~ £4r,8 _ _ a.1. ~5~ ~0.AO 

.61 

.1.3__ 

PREANDPOST-EMERGENCE \Dal. 4+2,4-D8 l~, 43 days after pre-em) 

Neburon 

Neburon 

2 

4 

27.3 

28.6 

6.9 

6.4 

.59 

.57 

14.6 

8.6 

.96 

2.30 

EPTC 4 22.7 4.1 .28 18.8 .68 

4Q 1.9.:.9 .~1__ 

gPIgHECK-TREATt7iE~TS - - ~5...2__ a.z .... 

Oats - 22.0 5.2 .35 18.6 .69 

Unweeded 21.0 4.0 .28 19.0 .80 

Grass Weeds Removed 22.9 4.4 .38 18.3 .59 

Broadleaf Weeds Rem. 20.6 5.0 .40 19.9 .68 

All Weeds Removed 25.2 4.9 .51 22.2 .72

Alfalfa: 

Root weight per plant was selected as a measure to compare 

the relative size of plants resulting from the various treatments. 

Again the pre-emergence treatments were shown to be generally superior. 

Neburon particularly with a follow-up post-emergence . 

treatment, resulted in ana~erage root weight per plant which was 

significantly greater then the.,unweeded check. EPTC, resulted in 

a significantly greater root weight per plant when used alone but 

failed to do so when followed by Dalapon and 2,4-DB. This may be 

explained in part as a result of the erratic behavior of the chemical. 

Greater average root weights also resulted from the use of 

DNBPat 1 1/2 lbs. per acre alone and in combination with Dalapon 

~t 2 lbS. per acre. The latter case at least agrees with the significantly 

higher yields obtained from the plots. 

Although no significance was determined, data on tillers per 

plant showed close agreement with the figures on root weight per 

plant. 

Birdsfoot Trefoil: 

Neburon applied alone and with a follow-up treatment of Dalapon 

plus 2,4-DB resulted in an average root weight of birdsfoot 

trefoil far greater than the check plots. This was true in spite 

of a reduced number of plants per square foot due to this treatment. 

These results indicate the importance of weed-free conditions 

for optimum development of birdsfoot trefoil. 

The value of a comparatively small number of large~ well 

established plants going into the first winter as compared with' 

a large number of poorly developed plants can be determined only 

when SUbsequent years' performance have been determined. It 

would apgear that in the light of greater ability to survive and 

compete with other plants t~is small number of sizable plants 

will have a decided advantage in producing a permanently productive 

stand. 

SU,I!!!!lary 

Pre- and post-emergence herbicides applied alone and in combinations 

were evaluated on spring seedings of alfalfa and birdsfoot 

trefoil during the 1958 season. 

Excellent weed control was obtained with Neburon applied 

pre-emergence at 2 or 4 lbs./A although 4 lbs. was required for 

best control of grass-type weeds. Highest yields of usable forage 

were obtained with Nebllron. Alfalfa was particularly responsive 

to this treatment and yields exceeded those of the 

handweeded check treatment. Neburon significantly reduced populations 

of blrdsfoot trefoil, particularly at the 4-pound rate. 

However, surViving plants developec rapidly in the absence of 

weed competition and yields of forRee were significantly greater 

than ,the unweeded check treatment. Neburon at the lower rate

186. 

(2 lbs.!A) followed by a post-emer~ence apPlic.ation. of Da1apon 

(4 lbs.!A) plus 2,4-DB (1 1/2 Ibs./A) effectively controlled all 

weeds. 

EPTC controlled grass-type weeds but was inconsistent with 

broadleaf weeds, results varying from good to poor. 

Control of most broadleaf and grass-type weeds was obtained 

with post-emergence applications of Dalapon at 2 or 4 Ibs./A 

plus 2,4-DB at 1 1/2 or 3 Ibs./A but with some injury to alfalfa. 

Neither chemical was satisfactory when used alone o 

DNBPand MCPAapplieC! alone or with Dalapon were not satisfactory 

because of ineffective broad leaf weed control. MCPA 

also resulted in some injury to alfalfa. 

Literature 

Cited 

1. Antognin1, J. Activity of EPTC as effected by soil moisture 

at time of application. Proc. 12 Annual Meeting NEWCCppo 

398. 1958. 

2. Hill, G. D. Soil factors related to herbicidal action of the 

sUbstituted ureaso Ag. News Letter 24:74-78, 1956. 

3. Hull, R. J. and Wakefield, R. C. The effect of selected herbicides 

- alone and in combination - on the establishment of 

legume seedings. Proc. 12 Annual Meeting NEWCCpp. 168-176. 

1958. 

4. Kerkin, A. J. and Peters, R. A. Herbicidal effectiveness of 

2,4-DB, MCPB, Neburon and other materials as measured by 

weed control and yields of seeding alfalfa and birdsfoot trefoil. 

Proc. 11.Annual Meeting NEWCCpp. 128-138. 1957. 

5. Schreiber, M. Mo , and Fertig, S. N. Preliminary results of 

pre- and post-emergence screening experiments on legumes. 

Proc. 8 Annual Meeting NEWCCpp. 313-317. 1954. 

6. Shaw, W. C. An efficient sprayer for application of chemical 

sprays to experim~ntal field plots. Agron. Jour. 42, 

pp. 158-160. 1950. 

7. Steinbauer, G. P., Grisby, B., Correa, L., and Frank, P. A. 

Study of methods for obtaining laboratory germination of 

certain weed seeds. Pr oc , Assoc. Off. Seed Anal. 45:48-52.' 

1955. 

8. Vengris, J. and Colby, W.C. Chemical weed control in new 

grass-legume seedings. Proc. 9 Annual Meeting NEWCCpp. 

305-311. 1955. 

; 1

Vengris, J. Annual weedy grass control in new legume seedings. 

Proc. 11 Annual Meeting NEWCCpp. 143-149. 1957. 


Acknowledgement is made to the Dow Chemical Co. for supplying 

Dalapon and DN to the AmchemProducts Inc., for supplying 

2,4- DB, to the DuPont de Nemours and Co. for supplyins Neburon 

and to the Stauffer Chemical Co. for EPTC.

188. 

Yields of Legume-forage Grass Mixtures as Affected by Several 

Herbicides Applied Alone and. in COf.binations During 

Establishment. 

vlarren E. Wells and. Robert A. Peters l 

Introduction 

Recent investigations have shown some new materials to be selective in pure 

stands of grasses or legumes (1,2,4). MixtuI'es of grasses and legumes are more 

cOllllllonlyused cormnercially than are pure stands. The next logical step is the 

development of herbicide treatments which will selectively remove both broadleaf 

and grassy weeds from legume and perennial grass mixtures. 

Greenhouse Experiment 

Materials 

and Methods 

The experiment was conducted during the spring of 1955. A split plot design 

was used with three replications for each legume-forage grass mixture. Plants 

were grown in #10 cans in soil which had a uniform high level of fertility. 

The legume-forage grass 8pQcies werel 

Vernal alfalfa - Lincoln smooth bromegrass 

Viking trefoil - Timothy 

Ladino clover - Orchard grass 

Rough pigweed (Amaranthus retroflexus) was sown in alfalfa-brome pots to 

provide a measure of weed control. Stands of all species were thinned to a uniform 

number after emergenoe. 

Chemical treatments were applied March 1, 1955 by pushing a sprayer similar 

to that designed by Shaw (3) over the pots. Legumes were in the 2-4 true leaf 

stage; while the forage grasses were 2 11 tall. Pigweed was in the 2nd true leaf 

stage. 

The chemicals used in the greenhouse eXJ:eriment and in a sUllllllerseeded field 

experiment are shown in Table 1. All materials were applied in 40 gallons of 

water per acre , 

Notes on observations "rare made throughout the experiment. Density of stand. 

ratings were made 1 month after spraying. Yields were ta.ken Hay 14, 1955 based 

on hand. separations of each species. Duncan I s multiple range test was used to 

compare the treatment averages at the .05 level. 

lResearch Assistant and Associate Agronomist, respeotively, University of Connecticut, 


TABLEL 

Chemicals Used in Greenhouse 'and Field Experinents. 

ConunonName 

Dalapon 

4(2,4- DB) 

Neburon 

Diuron 

Simazine 

CIPe 

Chemical Name 

2,2~dichloropropionic acid, sodium salt 

4(2,4-dichlorophenoxybutyric acid) diethylamine 

form 

3-(3,4 dichlorophenyl-l~methyl-l-N-butylurea) 

3(3,4-dichlorophenyl)-1,1-dimethylurea 

(2-chloro-4-6 bis(ethylamino)-3-triazine) 

isopropyl N-(3-chlorophenyl) carbamate 

Source 

Dow 

Amchem 

Dupont 

Dupont 

Geigy 

Amchem 

Effects 

2.0 Yields 

Yield data based on hand separations of the species is given in Table 2. In 

general, yield data agrees with the density ratings as to the trend over the various 

rates of each chemical. 

Alf ali a-Brome 

A comparison of all rates of each chemical indicates that Neburon treatments 

gave greatest yield of both species combined. Alfalfa yields were greater than 

the check while brome yields \rere only slightly less than the check. Dalapon, 

dalapon + 2,4-DB 3/4, dalapon + 2,4-DB 1;; and dalapon + neburon all had fairly 

good alfalfa yields but poor brome yields. Neburon + 2,4-DB treatnents showed a 

greater than check brome yield, but a much reduced alfalfa yield. 

Individual treatnents compared at the ;05 level indicated significantly higher 

yields of alfalfa at the 4# rate of neburon, while significantly lower yields of 

brome occurred at the high rate of dalapon ~4#) and the medium and high rates of 

dalapon + neburon. 

Pigweed 

Significant reduction in yields of pigweed occurred ~dth all chemicals except 

the 1 and 2 lb. rates of dalapon, dalapon + 2,4-DB (2+3/4), am the dalapon 

+ 2,4-DB (4+1;). Laok of pigl'leed control with dalapon alone was expected although 

the higher rates do exhibit some control of this weed. Some variation in 

pigweed stands was noticed. Experience has shown that the choice of short day 

weeds for greenhouse experiments was a poor one due to maturity of the weeds 

while still very small. 

Trefoil-Timothy 

Yields of trefoil-timothy were best under dalapon, and dalapon + 2,4- DB 3/4 

treatments. As was noted in the density ratings, timothy showed a marked tolerance 

to dalapon and this is expressed in yields. Birdsfoot trefoil also showed

19C. 

TABLE2. Yields of Legume-forageGrass Mixtures and WeedsFollowing Early - 

Post-emergence Treatment with Herbicides. 

,greenhouse·Experiment. 

Yield in grams oven dry per plot 

Treatment Rate Alfalfa Brome' Pigweed BFT TimothY' Ladin~ Orchard 

Dalapon 1 4~3 2.3 1.3 3.3 4.3 7.') 3.3 

Dalapon 2 4.0 1.6 1.6 2.6 4.3 5.3 4.3 

Dalapon 4 5.0 .6* .6* 4.0 2.6 3.3 2.0 

Dalapon+2,4-DB 1+3/4 4.3 1.3* 0* 3.0 4.6 5.0 4~0 

Dalapon+2,4-DB 2+3/4 5~0 2.3 1.3 3.3 4.6 6.3 2.6 

Dalapon+2,,4-DB 4+3/4 4.6 1.6 1,0* 2.3 4.0 3.0 4.6 

Dalapon+2,4-DB 1+1y 6.6 2.3 0* 2~0 5.0* 6.0 3~6 

Dalapon+2,4-DB 2+1; 3~0 2~6 .3* 1.3 5.0* 3~6 3.6 

Dalapon+2,4-DB 4+1 3.3 2.0 1.3 .6* 5.3* 3.6 3.6 

Neburon 2 4.6 2;6 o~~ 1.6 4.3 6.0 4.3 

Neburon 4 8.6* 2.3 .3* 1~6 4~6 4~3 3.3 

Neburon 8 5.0 3.6 .3* 2.0 2.6 3.0 1.6 

Neburon+2,4-DB 2+3~4 1.3 3.6 o~~ 

0.5* 4.6 4.0 3.6 

Neburon+2,4-DB 4+1 1~1 3.3 0* 0.3* 3~3 1.0* 3~0 

Neburon+2,4-DB 8+3 1.6 3.3 0* 0.3* 2.3 0* 5.0 

Dalapon+Neburon 2+2 2~3 3~, 0* O;S- 4.6 0* 4.0 

Dalapon+Neburon 2+4 5.3 1;3* 0* b~3* 3.3 0* 3.0 

Dalapon+Neburon 2+8 5.0 1.3* 0* .0.0* 3.0 .0* 1.1 

1)iuron i 5;0 3~0 0* 4.6 1.3* .6* 0 

Diuron 1 3.0 3;3 0* 4.3 0* 0* 0 

Diuron 2 3.0 2.6 0* 2.0 0* 0* 0 

------------------------------------------- 

Check-Normal 4.6 3.0 2.0 2.6 3.3 7.0 2.3 

Averageof all rates of each chemical 

Dalapon 4.4 1.5 1.2 3.3 3.7 5.3 3.2 

Da1apon+2,4-DB3/4 4.6 1.7 0;8 2.9 4.4 4.8 3.7 

Dalapon+2,4-DBII 4.3 2~3 0~5 1.3 5.1 4.4 3.9 

Neburon 6.1 2;.8 O~2 1.7 3.8 4;4 3.1 

Neburon+2,4-DB 1.3 3;4 0.0 0~4 3.4 1.6 3.9 

Dalapon+Neburon 4.2 2;0 O~O 0.4 3;6 0.0 2;7 

Diuron 3.6 3.0 0.0 3.6 0.4 0.2 0.0 

* Denotes significance from check at .05 level. 

~.~

191. 

a tolerance to dalapon and to the dalapon + 2,4-DB treatments. Individual tre&tments 

showed significantly lower trefoil yields for neburon + 2,4-DB, the medium 

and high rates of dalapon + neburon and the high rates of dalapon + 2,4-DB 1~. 

Significantly lower yields of timothy occurred under all diuron treatments. The 

significantly higher yields of timothy under all rates of dalapon + 2,4-DB 1* can 

be explained in part by the reduced stand of trefoil, resulting in less competition 

to the timothy stands. 

Ladino-Orchard 

Yields of these species again closely'followedthe pattern established in 

the density ratings. Dalapon, dalapon + 2,4-DB 3/4, and dalapon + 2,4-DB l!, were 

the best treatments in that order. Significantly lower yields of ladino occurred 

under the medium and high rates of neburon + 2,4-DB and all rates of dalapon + 

neburon, and diuron. There were no significant differenoes in orchard grass yields, 

although diuron treatments completely eliminated orohard grass stands at all rates. 

Field 

Experiment 

Materials 

and Methods 

A field experiment was established August 28, 1957. A randomiz ed block design 

was used with four replicateb for each legume-forage grass mixture. The individual 

plot size was 6! x 6*feet. 

The forage species seeded were as follows: 

Vernal alfalfa - Lincoln smooth brome 

Viking trefoil - Timothy 

Ladino olover - Orchard grass 

All seedings were broadcast seedings made with a grain drill. No weed species 

were seeded since a desirable volunteer weed stand was expected. A high uniform 

level of fertility was established. 

The chemioals were applied September 25, 1957, with a sprayer modeled after 

that designed by Shaw (3). At the time of application of the chemioals, the legumes 

were in the 2-4 true leaf stage and the forage grasses were 2-3 inches tall. 

The volunteer weed population consisted primarily of commonand mouse-eared chickweed, 

and scattered lambsquarter and red sorrel plants. Weather at the time of 

application was clear and cool. 

Stand counts ''lere made before and after spraying. Stand counts before spraying 

were made in check plots in each replication, and these were taken to represent 

the stand of the entire field. Post spraying stand counts were made October 23, 

1958, 28 day'S after spraying. Density of stand ratings \'!ere also made to supp1ement 

observation and stand counts. 'Stand counts were again made r.1ay9, 1958 to 

give an indication of overw.l.ntering. 

Fir8t outting yields were obtained June 23, 1958. Plots """re ha.rvested. by 

mowing a 39" swath through the center of each plot and yields were based on hand 

separation of a sub-sample of each plot. A second cutting was made August 18,

1)2 • 

1958. Ladino-orcnard plots' wer~'rtbtr harvested' since 1;he stand did notovermnter 

due to insufficient ti.mefd%' ·e-stab!tl..shment between seeding and winter 1957-1958. 

Treatment averages for stand· CbUhtsand yields were compared at the ,05 level 

using Duncan IS r·iultip1.e Range'tElIftl. ~ 

Fall Stand Counts 

Results ~ Discussion 

Fall stand counts given in Table 3 did not show appreciable differences in 

stands for most species. Alfalfa, brothe and birdsfoot trefoil stands showed no 

significant differences from the check. Timothy stands were significantly lower 

at the 2 and 4 pound rate of simazine, the medium and high rates of dalapon + 

2,4-DB, and at the high rate' of CIPC, Ladino stands were significantly lower at 

the 4 pound rate of sirilazine, the high rate of neburon + 2, 4-DB, and the medium 

and high rates of dalapon + neburen, Orchard stands were significantly lower at 

all rates of s1ma.zine, the high rates of dalapon + 2,4-DB and neburon + 2,4-DB, 

the low and medium rates of da'laporr + neburon , and the medium and high rates (2 

and 4 pounds) of CIPC. 

A comparison of chemicals (average of all rates) indicates no appreciable 

difference in stands of alfalfa. Brome stands were somellhat greater under nebnron 

and neburon • 2,4-DB, and clearly 10'l'ler with da lapcn + neburon treatments. 

Trefoil stands were 10\'1er with neburon + 2,4-DB treatments. Timothy stands were 

sharply reduced by simazine treatments, while some reduction of stand occurred 

with da1.apon + 2,4-DB and CIPC largely attributed to the higher rates. Ladinoorchard 

sbard s were' greatly reduced with simazine and dal.apon + neburon treatments. 

Dalapon +'2,lJ-DB, neburon, neburon + 2,4-DB, and CIPC shovred the most 

promise on ladino, while orchard stands generally appeared better with neburon 

and neburon + 2,4-DB treatments. 

Spring Stand Counts 

Spring stand counts given in Table 4, were taken to ascertain differences 

in overwintering as related to establishment. All species showed greater differences 

smong treatments than was evidenced in the fall counts. Due·to slo\oler 

activity of the herbicides at this time of year, fall counts did not show the 

eventual effects on establishment. The spring stand counts definitely related 

establishment to herbicidal treatments. 

, Alfalfa stands'l'IBre significantly reduced by Simazine (4 pounds), dakapon + 

2,4-DB 1!+2 and 3+2, and CIPC at the 4 pound rate. Simazine and dalapon + 2,4DB 

at all rates showed step by step decrease in stands with increasing rate, while 

neburon treatments were all higher than the check but not significantly so. 

Brome stands were significantly lower "Tit~ the 4 pound rate of simazine, 

dalaPOn + 2,4-DB 1~+2 and 3+2, all rates of da1.apon + neburon, and the 4 pound 

rate of CIPC. Brome stands were best under neburon and neburon + 2,4-DB treatment:.s • 

. Weed stands in alfalfa-brome l'IBresignificant~"y lower than the check in" all -' 

treatment.s exce,pt:the three rates of dalapon + 2,/~-DB, neburon + 2,4....DB, 4+2, and

"- 

\?J. TABL 3. Fall Stands of Leguma-rorege Grass Nixtures Following Early Post- 

EmergenceTreatment with Herbicides. 

~~~2Sq. Ft. 

Quadrat 

Treatment Rate Alfalfa Brome BRT Timothy Ladino Orchard 

Sirilazine 1 38 14 19 29 9 5~~ 

Simazine 2 40 13 15 23* 8 1* 

Simazine 4 31 10 22 13* 3* 

1~~ 

Dalapon+2~4-DB 3/r 

2 34 16 15 38 20 7 

Dalapon+2~4-DB 1 +2 31 8 17 27* 12 6 

Dalapon+2~4-DB 3+2 31 11 12 15* 12 2* 

Neburon 2 34 15 17 39 20 10 

Neburon 4 35 15 19 37 19 9 

Neburon 8 34 13 18 37 9 6 

Neburon+2~4-DB 4+1 29 16 14 36 15 7 

Neburon+2,4-DB 4+2 33 13 14 35 9 8 

Neburon+2,4-DB 4+4 32 17 12 39 5~~ 5* 

Da1apon+Neburon 

ir2 37 5 16 36 10 4* 

Dafapon-Neburon 1 +4 31 9 1~ 33 4* 4* 

Dalapon+Neburon 1 +8 38 7 13 34 3* 6 

CIPC 1 31 11 18 29 21 6 

CIPC 2 34 11 20 35 15 5* 

CIPC 4 30 8 16 24* 18 4* 

- - - - - - --- - - - - --- -------------------------- 

Check-Normal 35 11 19 38 18 10 

Average of all rates of each chemic'll 

Simazine 36 12 19 22 7 2 

Dalapon+2,4-DB 32 12 15 27 15 5 

Neburon 34 14 18 38 16 8 

Neburon+2,4-DB 31 15 13 37 10 7 

Dalapon+Neburon 35 7 15 34 6 5 

cnc 32 10 18 29 18 5 

* Denotes significance from check at ,05 level.

194. 

TABLE4. 

Spring Stand of Legume-forage Grass Mixtures Following Early Post- 

EmergenceTreatment \'11th Herbicides. 

~Counts Per 2 Sg. Ft'.'Q,ua.drat 

Normal + 

Treatment Rate 

Heaved Alive 

Alfalfa Brome 

vleeds in 

Alf-Brome BFT 

Weedsin 

Timothy EFT-Tim 

Simazine 1 14.25 8.25 0.00* 0.00* 5~75* 0~00* 

c'" imaz i.ne. 2 9.00 4.75 0~25* O.OO;} 0.00* O.OOi~ 

Sin:a.~ine 4 1.75* 0* 0.25* 0.00* 0.00* 0.00* 

Da1e.pon+2,4-DB 3/4+2 14.75 7~25 3.75 8~25 22~50 2.25 

Dalapon+2,h-DB li+2 3~25* .75* 6.00 3~75* 21~75 4~25 

Da1apon+2,4-DB 3+2 o.oos Qit 4.25 .• 25* 19.25 3.50 

Nebur-on 2 19.75 10~50 1.75* 9~75 19;00 ~50* 

Neb-ir-on 4 20;00 12.00 ~50* 10.25 18.00 .• 75* 

Neburon 8 18,50 8.25 .75* 1.50* 17.00 , .25* 

NebUI'on+2,4-DB 4+1 17.00 11.00 1.25* 2~50* 18.00 1;00 

NebuI'on+2,4-DB 4+2 15.25 9.00 3~00* 4.00* 21;75 .50* 

Neburon+2,4-DB 4+4 13.25 13.50 .50* 1.50* 21.50 1.00 

Da1apon+Neburon 

lr 

2 9.50 ~50it .-75* 3.00* 20.00 0.00* 

Dalapon+Neburon 1 +4 10.75 2.00* ~50* 0;00* 19.00 0;00* 

Dalapon+Neburon 1 2+8 8.50 0.00* .50* 1.25* 19.25 0.00* 

CIPC 1 i5,50 5;25 3~00 1~75* 7;50* 1;25 

CIPC 2 19;25- 4;25 ~50 ;25* 2~75* 0.00* 

CIPC 4 3.75* 2.00i} 0.00* 0.00* 0.00* 0.00* 

-------------------------------------------- 

. . . . . 

Check-Normal 14.75 8.75 5.75 10.75 16.75 2.25 

Average of all rates of each chemical 

Simazine 8.33 4~33 ~17 0.00 1;92 O~OO 

Dalapon+2,4-DB 6.00 2~66 4.66 4.08 2l~17 3.33 

Neburon 19.41 10.25 1.00 7;17 1$~00 0.50 

Neburon+2,4-DB 15.16 ,11.17 1.58 2.66 20;4.2 0;83 

Dalapon+Neburon 9.58 0;83 0.58 1~42 1S'~4.2 0;00 

CIPC 12.83 3.83 1.16 0.66 3.42 0.42 

* Denotes significance from check at .05 level.

195. 

the low rate of CIPO. The high weed population with all rates of dalapon + 

2,4-DB is attributed to reduced competition from alfalfa-brome, and to lack of 

injury from this herbicide combjnation. 

Trefoil stands \1ere significantly lower than the check for all treat~nt8 

except the low rate of dalapon + 2,4-DB, and the 2 pound and 4 pound rates of 

neburon. Simazine at all rates was particularly hard on trefoil. Trefoil 

stands in general appeared to be handicapped by an unfavorable balance with 

timothy, resulting in excessive competition from the vigorous timothy stands. 

Timothy counts were significantly lower with all rates of simazine, and all 

rates of CIPO. Dalapon + 2,4-0B, neburon, neburon + 2,4-DB, and dalapon + 

neburon treatments at all rates showed stands slightly greater than the check. 

Weed populations in trefoil-timothy stands were very similar to weed populations 

in alfalfa-brome stands. None of the rates of dalapon + 2,4-DB were 

significantly lower than the check. 

Effects 

~ Yields 

Yield data for the first cutting in the year following seeding is presented 

in Table 5. Alfalfa yields 1'!ere significantly lower than the check at the 2 and 

4 pound rate of simazine, 'l!+2 and 3+2 pound rate of dalapon + 2,4-DB, .1!+8 .pound 

bate of dalapon + neburon, and the 4 pourd rate of CIPC. All rates of neburon, 

and the 1 and 2 pourd rates of CIPC were higher than the check. 

The 2 and 4 pound rates of simazine, li+2 and 3+2 pound rate of dalapon + 

2,4-0B, all rates of dalapon +neburon and the 2 and 4 pound rate of CIPC reduced 

yields of brome significantly from the check. Neburon ani neburon + 2,4-0B 

treatments had yields of brome generally higher than the check although not significantly. 

Weed yields in all plots for the first cutting were primarily common"and 

mouse-eared chickweed'. Lowered weed yields occurred from simazine, neburon, 

dalapon + neburon, and CIPC treatments. Chic}aieed appears to be resistant to 

2,4-0B as it is to 2,4-0. 

Trefoil yields 1-lere noticeably low for all treatments, resulting from excessive 

competition from timothy stands. All treatments except the low and medium 

rates of dalapon + 2,4-DB, and neburon,showed signitieantly lO~ler yields than 

the check. Simazine was extremely active on bothtre.foil ani timothy stands, 

eliminating all vegetation or reducing ,ahe stand to. only a few stunted plants. 

TimQthyyields generally followed the pattern of trefoil. The low and 

medium rates of dalapon + 2,4-0B, neburon, am the medium rate of neburon + 2,4OB 

were the only treatments not significantly lower than the check. It appears that 

timothy may have 'even competed \'lith,itself in llome cases due to its extremely 

heavy population. 

~ Cutting Yields 

Seco~_ ~utti~ yie~ds showed less variation bet\'leen treatments than first

196. 

TABLE 5. 

. - . '. : t~ ~,: 

First Cutting Yields of. Late SummerSeeded Legumes-f.orl\.teGrass .: 

Mixtures Following Herbj,cide Treatments. . : 

Yields - Pounds.Oven-dn m Acre 

; Weeds 

~: 

in ' Weedsiri 

Treatment Rate Alf'aila Bl'Gme AU-Brome BFT Timothy . 'BFT.;.T:D€' 

Simazine 1 376 1428 103* 0* 0* 

Simazine 2 57* '_145* 1* 0* "g:f- 0* 

Simazine 4 0* 0* Oi~ 0* 0* 0* 

Dalapon+2;4-DB 3/4·2 505 2634 572* 77 5959 113 

Dalapon+2j4-DB 1~+2 103* 150* 567* 60 5274 57i~ 

Ja1a!,on+2,4-DB . ,3+2 1* 42* 124* 1$* 1722* 69* 

Neburon 2 1165 2996 144* 62 5743 67* 

Neburon 4 1041 2701 207* 72 5701 15* .. 

Neburon 8 959 1603 82* 14* 3598* 5* 

Neburon+2j4-DB 4+1 583 2769 452* 19* 4093* , 3~'.' 

Neburon+2i4-DB 4+2 531 2882 248* 16* 4861' ' 1'9*.,,. 

Neburon:+2,4-DB 4+4 567 ' 2356 21,6* '5*' 3758* 31*.. 

Dalapon+Neburon 485 181* 98i~ 23* 3925i~ 4* 

Dalapon¥Neburon 1~2 14 593 129* 407* 8*" 3598* ,0* 

Dalapon+Neburon 1+8 ' 2J.7* 52* 5* 0* ,3098* , 0* 

CIPC 1 1418 1248 521* 5* 1510* 57* 

CIPC 2 1294 521* 86* 37* 278* 12* 

CIPC ,4 175* 52* 40* 0* 0* 0* 

- - ---.- .• '~ --.-- 

...,- - ---.,,-,--------- _.- -'~ 

- -_..... :--.--,--.-- 

" .. "'. -'. " . . . ",' . 

Check-Morma1 897" ' 2036 846 124 6454 206 

~verage of. all rates of. each chem;ca1 

Simazine 144.:33 524.33 34~66 0 0' 0 

Dalapon+2,4-DB "203;00 ' 942;00 421~OO ' 50.66 . 4318.:3:3 79~66 

Neburon '1055~OO 2333;33 144.33 49S3 5014.00 ' 29.00 

Neburon+2,4-DB ' ~60.33 2669~00 305;33 13;33 4237;33 27.33 

Dalapon+Neburon 43L66 120;66 170.00 10;33 3540~33 1~33 

CIPC 962~3' ~07.00 215.66' 42.00 ' 596.00' ,23.00 

.. 

* Denotes eignificancetrom check at ;.05 level.

7. Trefoil-timothy rields show a selectivity to dalapon + 2,4-DB treatments at 

+""...., ..... ".'1'o't"'\...t _~';..,.m "..~+.c.C!! ThA ""..jan"'~+.AQ ;n Mt.h t.P.Rt..C\ ~ ,O'nir;~...qnt',v reduced 

198. 

harvest again proved the most promising, while the poorer treatments werQ generally 

lOHest in yield. These data are given in.Table 6. 

-", 

Alfalfa-brome yields were lCMered \'Jith increasing rates of both sioazine 

and the dalapon+ 2,4-DB combination. Brf1llleyields were significantly 101'rer 

with all rates of dalapon + neburon, and CIPC. The' two pound rate of CIPC gave 

yields sienificantlyhigher than the check which cannot be adequately explained. 

Weed yields' were significantly higher with the medium and high rates of 

dalapon + 2,4-DB, and the 4pounil'ateof CIPC. All other treatments sho~red no 

significant diflerences' in l-reedyields. Weed yields in trefoil-timothy stands 

were also si~ificantlY higher lnth all rates of CIPC. Weed yields in these 

treatments showing significant increase was due to the influx of volunteer witchgrass 

(Panicum capillare). Lessened competition from the chickweed, legume, 

or forage grass allo\'red l-.ritchgrass to develop rapidly. Simazine treatments 

suppressed the encroachment of volunteer \"leeds due. to the residual herbicide 

in the soil. 

Comparison of trefoil-timothy yields showed that all treatments except the 

low rate of dalapon

199. 

8. Hixturee oontaining neburon, namely, neburon + 2,4-DB and dalapon + neburon 

treatments in both tests 10\lered trefoil yields significantly. Their effect 

on timothy is conflicting sdnee yields in the field were significantly reduced 

while yields in the greenhouse vrere sliihtly greater than the check. 

9. Neburon treatments in the 

greenhouse test indicate. 

fie]1 sho'"ed more promise 

Only at the 8 pound rate 

than the results of the 

were yields of trefoiltimothy 

reduced significantly from the check. 

10. Simazine and CIPC proved too severe for safe use on trefoil-timothy. All 

plants were killed with the 2 and 4 pound rates of simazine. Only a few escaped 

complete kill at the 1 pound rate of simazine. 

11. Neburon and mixtures containing neburon gave good chfckweed control as did CIPC. 

12. Fall" stand counts did 

ever, good correlation 

not correlate well with yields the following 

was noted between spring stand counts (after 

spring; how 

overwintering) 

and first cutting yields. Forage species injured from herbicide treatments in 

the late'summer seeding did not have sufficient time to recover before winter 

donnancy. 

13. Hi.xtures 

binations 

including 

were not 

dalapon, namely dalapon + neburon and dalapon 

promising on alfalfa in this summer seeding, 

+ 2,4-DB com 

Other eJqeriments 

point out this effect which is in 

been reported on many spring seadings. 

contrast 

Alfalfa 

to the results which have 

yields were greatest with 

neburon treatments, while bromegrass yields were greatest with the neburon + 

2,4-DB treatments. 

14. The most premising chemicals 

and neburon, The combination 

for trefoil-timothy stands were dalapon + 2,4-DB 

of dalapon + 2,4-DB gave slightly higher yields 

of trefoil than did neburon, while neburon gave slightly higher yields of 

timothy in the field experiment. 

15. Low rates of dalapon + 2,4-DB appear to offer the most promis e for ladinoorchard 

starrls. Diuron was notioeably toxic to Jadino claver. 

16. Future experimentation with herbioide combinations should probably include 

lower rates of eaoh oomponent. Possible additive and synergistic effects c 

oould thus be more easily recognized. 

T,ihrature 

Cited 

1. Hull, R. J. and vlakefield, R. C. The Effect of Sebcted Herbicides - Alone 

and in Combinations - On the Establishment of Legume Seedings. Proc , 

NE\tJCC12: 168-176, 1958. 

2. Kerkin, AlbertJ. and Peters, ~obert A. Herbicidal. Effectiveness of2,4-DB, 

MCPB,Neburon and Other Ma.terials as Heasured by \'1eed Control and Yields 

of Seedling Alfalfa',!-rid Birdsfoot Trefoil. Proc , MEVlCC11:128-138. 1957. 

3. Shaw, ,W. C., An Erf:i.cie~t Sprayer for Application of Chemical Sprays to Experimental 

Field Plots. Agron. Jour. 42:158-160. 1950. 

4. Vengris, J. Annual \'leedy Grass Control in New.Legume Seedings. Proo , NEWCC 

11: 143-149. 1957.

20n. 

IATE SUMMERSPRAl'INGOF OAK-MAPII ~USH 

R~·J. 

by 

Hut.nik and W. R. ,Byrne,;!! 

A spray crew using careful. and thorough application oan. spray woody 

brQ,eh in June and get almost complete kill. The same crew, with the same 

chemicl/.I, on the same type of brush, and using the same methcid and care of 

application, may get a very poor kill following spraying' in late August. 

This seasotl.al variation in effectiveness· of chemical spraying is one of the 

big problems facing men who are charged with maintaining rights-of-way in a 

brush-free condition. 

: Amongthe solutions to this problSll that have been suggested are: 

(1) that the concentration and volume be increased as the growing season 

progresses, (2) that oil be added to the water carrier during late season 

spraying, and. (3) that the proportion of oil in oil-water emulsions be 

increased as the seaeon progresses. To partially evaluate these suggestions, 

a study was setup .in Central Pennsylvania in 1951. The specific objective 

was to compare the effectiveness of five different sprays applied durPJilate 

summer. Three different chemicals and two different carriers were used in 

this study. 

Procedure 

The area chosen for the study was a portion of I/. lBO-foot wide Penelec 

right-of-way on the south-facing slope of Tussey Mountain in Huntingdon County, 

Pennsylvania. The right-of-way had been cut through an even-aged mixed oakmaple 

forest during· the winter of 1951-1952,; This mixture of species is ' 

typical of the ridge and valley section of the oak;.ehestnut forest type. The 

dominant species present is chestnut oak in association principally with red 

oak and red maple, and to a lesser extent with scarlet oak, black oak, white 

oak, and black gum (Table 1). The ground layer is composed of grasses, woody 

shrubs, and herbaceous ;pllil,nts with blueberries, hUckleberries, and mountain 

laUrel as tlle major constituente. 

Following cutting, the stumps ,sprouted prolifically. By August, 1951, 

these sprout clumps had attained an average height ofll feet. wit,h occasional 

clumps exceeding 20 feet in height. In addition, ~ seedlings became 

established during the years following cutting. By 1951,. most of these 

seedlings were still in the ground layer; nevertheless, they constituted a 

potential brush problem. 

Although species composition was relatively uniform over the entire test 

area (Table 1), brush density did vary. TherefO!'e, the test area was divided 

y Members of the staff of the School of forestry, Th~ Pennsylvania state 

University, Urdversity Park, Pennsylvania.

4. 2,4,5-TP in water. 2-(2,4,S.trichlorophenoxy) propionic acid 

applied at a concentration of 61bs. acid equivalent per 100 gallons of water 

~R ~ Rtem_folia~e snrav. 

201. 

into two blocks--one in which the, brush density averaged' about. 35 percent and 

another in which it averaged about 55 percent. 

Table 1. Species cC':lIposition on treatment areas based 

on sprout clUmps of atumporigin. 

--------------~:~:---~OO~s--~~r~-----B~~- 

!.r2, 

, nut Red othe rll Red Hard- Total 

a1m2, n1 0!k__ 0!k__ O~!! _~~e_!o,2d!! _T,2t!l_ ]~~t¥L 

,percent} 

,no.} 

Control 47 23 14 15 1 100 145 

D + T esters in water 62 13 8 17 

100 176 

D + T eaters in oil-water 68 17 2 12 ° 1 100 139 

2,4,5-TP in water 66 16 7 ,9 2 100 182 

2,4,5-TPin oil-water 67 9 7 ~6 1 100 176 

D + T amine in water 60 17 7 ,],1 5 100 131 

All treatments 62 15 7 14 2 100 949 

1I.Includes scarlet oak, black oak, white oak, and scrub oak. 

Y Includes witch hazel, black gum, hickory, black birch, shadbush, and 

butternut. 

21Total' of two randomly located' 1/2-acre plots. . 

Each block consisted of 6 plots,1/2-acrein size. A 100 percent tally 

was made of the woody brush on each plot. As to be -expected, the most serious 

brush condition was the sprout clumps that originated from atumps. Therefore, 

a separate tally was made of U"..s class of woody brush. This tally provided 

the basis for the initial evaluation of the treatments. . 

The atudy consisted of six treatments, randomly assigned to the six plots 

in each block. They are summarized in Table 2. In more detail, they were: 

1. An untreated c'ontro1. 

2. D + T eaters in water. A half-and-half mixture of butoxy 

ethanol esters of 2,4-D and 2,4,5-T applied at a concentration of 6 Lbs, acid 

equivalent per 100 gallons of water as a stan-foliage spray. 

3. D + T esters in oil-water. A half-and-half mixture of butoxy 

ethanol esters of2,4-Dand 2,1;,,5-Tappl1ed at a concentration of 6 1bs. acid 

equivalent per 80 gallons of water and 20 gallons of' No. 2 fuel oil as a semibasal 

spray.

2()2. 

5. 2,4,5 ..TP in oil-water. 2-(2,4,5-trichlorophenoxy) propionic 

acid applied at a concentration of 6 lbs. acid equivalent per 80 gallons of 

water and 20 gallons of No. 2 fuel oil as a semi-basal spray. 

6. D + T amine in water. A half-and-half' mixture of amine salts 

of 2,4-D and 2,4,5 ..T applied at a concentration of 6 lbs. acid equivalent 

per 100 gallons of water as a stem-foliage spray. 

Table 2. Brief description of the late SUlllIllerchemical treatments. 

Chemical 

Concentration 

Carrier 

Technique' 

D + T Fsters 

D + TEsters 

2,4,5-TP 

2,4,5-TP 

D + T Amine 

6 Ibs. ahg 

6 lbs. ahg 

6 lbs. ahg 

6 Lbs , ahg 

6 Lba, ahg 

water 

oil-water 

water 

oil-water 

water 

stem-foliage 

semi-basal 

stem-foliage. 

semi-basal 

stem-foliage 

These chemicals were chosen because they have all been widely used with 

good results on this type of brush, especially during the earlier part of the 

growing season (2,3). A concentration of 6 lbs. per 100 gallons rather than 

the more customary 4 Ibs , was used to increase the likelihood of obtaining a 

good kill even in the late summer. For the same reason, the proportion of 

oil in the oil-water sprays was 20 percent instead of the more customary 10 

percent. To insure proper emulsification with this relatively high proportion 

of oil, the 2,4-D + 2,4,5-T esters and 2,4,5-T propionic formulations used in 

the oil-water sprays contained slightly more emulsifiers than those used in 

water. The commercial brushkiller formulations now on the market contain 

these additional emulsifiers. 

The treatments were applied during the period from August 19 to August 23, 

1957. Spraying was done with a Bean Royal 7 pump unit and a Bean Spray-Master 

spray gun. This unit together with a 150-gallon main tank, a loo-gallon 

reserve tank, and 275 feet of rubber hose was mounted on a Jeep pick-up. A 

No. 8 nozzle was used and a pressure of 300 Lba, was maintained at the pump 

during spraying in all the plots. 

With water as the carrier, the stem-foliage technique was used. This 

technique is fully described in the 1958 Report of the Research Coordinating 

Committee on WoodyPlants (2). Briefly, it consists of wetting the foliage 

with a fine spray to the dripping point and then wetting stems with a coarser 

spray until rundown occurred to the ground line. 

With an oil-water ndxture as the carrier, the semi-basal technique was 

used. This consisted of thoroughly wetting the stems at the base with a coarse ..-/ 

spray (narrow cone), then proceeding up the stems with a finer spray until run-

203· 

down occurred, and then spraying the foliage to the dripping point with a fine 

spray (broad cone) to a height 'If about 4/5 of the clump. 

Under both techniques, the clumps were sprayed fran opposite sides to 

insure thoro-ugh coverage. Aleo, special care was taken to spray the small 

tree seedlings almost hidden in the ground cover. 

A record was kept of the quantity of spray solution applied on each plot. 

In general, there was a good relationship between the amount of brush on a 

plot and the quantity of spray applied. The plots in Block I, which had only 

about 35 percent brush density, received an average of 117 gallons on a halfacre 

plot. The plots in Block II, which had about 55 percent brush density, 

received an average of 176 gallons. Thus, in view of the light brush density, 

the quantities applied were high--equi valent to over 600 gallons per acre on 

brush of 100 percent density that ranged up to 20 feet in height. 

Results 

In August, 1958, another 100 perc&nt tally was taken of all the woody 

brush on the treated plots. In addition, a more detailed tally was made of 

the clumps of stump origin. Each of these clumps was placed into one of the 

following three classes: (1) complete topkill, not resprouting; (2) complete 

topkill, resprouting; and (3) incomplete topkill. The number of resprouts and 

the number of original stems still living were also recorded. 

Although only one year had elapsed since treatment, the results were so 

striking that a detailed analysis of the data was warranted. At the same time, 

it was recognized that the complete story is yet to be unfolded as more of the 

clumps die and others resprout :luring the next few years. 

The kill ranged trom poor to excellent without any clearcut differences 

between the two blocks or among the three chemicals (Table 3). However, tho 

carrier that was used made a big difference in the results. For example, 

those plots which received an oil-water spray showed an average of 80 percent 

complete kill compared to only a 17 percent kill in the plots which received 

a water spray. These figures are for clumps that were completely killed to 

the ground line and have not resprouted. 

For topkill alone, tho difference was even more pronounced. This figure 

is obtained by combining the data for "complete topkill, not resprouting" and 

"complete topkill, resprouting" as given in Table .3. There was somewhat more 

resprouting following spraying ldth an oil-water carrier than with a water 

carrier. This is especially apparent with the 2,4...n + 2,4,5-T esters. 

However, as past experience has shown (1), it is probable that many of these 

sprouts will die in the ensuing years.

204. 

Table 3. Percent kill of sprout clumps of stump o~ 

1 year following spraying. All species combined. 

- - - - - - - - - - - - - -CompleteTopkln -CompleteToP'Jdl:l - -Incomplete- 

Treatment· Not Resnrout-l,..,O'. Resyroutin g Tonkill 

-----------------=~~.~--- . m, -I m, ·J.I m, -~-~--~--~--I- 

BJ.. J.J. BJ.. I si, I 

D + Testers in water 

D + Testers in·ail-water 

2,4,5-TP in water 

2,4,5-TP in oil_water 

D + T amine in water 

22 

78 

24 

98 

48 

9 

1 3 

79 171oo 

12 

72 

4 

16o6 

2 

77 5 

75 

2 

52 

88 

5 

88 

22 

94 

. If· the 2,4:"n + i,u,5-r~e treatments are eliminated, it i~' possible 

to make a detailed statistical analysis of the data. In effect then, this 

experiment is a factorial design of two blocks, two chemicals, and two 

carriers. In, addition, since both the oaks and red maple are well represented 

on all plots, the reaction of these two species .groupa to the treatments 

can also be evaluated (Table 4). 

Table 4. Percent topkill, not resprouting, of oak and red maple 

sprout clumps 'of stump origin 1 year following spr¢ng. 

--------------------O~--------Ld~~e--- 

£h~!.c~l C~i.!!r BJ:o£k_I_ ~l2.c~ !I BJ:o£k_I_ !!l2.c~ !I_ 

D + TEsters 

D + TEsters 

2,4,5-TP 

2,4,5-TP 

Water 

Oil-water 

Water 

Oil-water 

20 6 

73 76 

19 6 

98 67 

36 

100 

55 

100 

14 

100 

42 

88 

This analysis shows that the differences in the kill between carriers 

and between species were highly significant (Table 5). As mentioned before, 

the oil-water carrier resulted in· better control. Also, red maple was more 

easily killed than were the oaks. On the other hand, the differences in 

kill between chemicals and between blocks were not significant; that is, 

they could easily have been due to chance alone. None of the interactions 

were significant except the one between species, chEllli.cal, and carrier. This 

means that the difference in kill between species varied with different cambinations 

of carriers and chemicals. This is more clearly seen in Figure 1. 

With the water carrier, red maple was more easily killed by 2,4,5-T propionic 

than by the. 2,4::D+ .2,4,5-T ,esters. The opposite was true for the oaks •. With 

the Oil-water carrier, the results were reversed, red maple being slightlymore 

susceptible to the 2,4-D + 2,4,5-T esters with the oaks slightly more 

susceptible to 2,4,5-T propionic. The' graph further suggests that fair control 

of red maple might be possible with 2,4,5-T propionic in a water carrier 

as a late-season spray. This is not true of the oaks or if the 2,4-D +

205. 

Table 5. Evaluation of the differences in kill by variables 

and their interactions. Oak-maple sprout clumps of 

stump origin 1 year following spraying. 

--------------------------Ew!~t~n~------ 

---y~~~-------------------~¥~~£~------ 

Chemical 

Carrier 

Chemical x Carrier Interaction 

Species 

Species x Chemical Interaction 

Species x Carrier Interaction 

Species x Chemical x Carrier 

Not significant , I 

Highly significant.:t 

Not significant 

Highly significantY 



Sign1ficantY 

1/ Significant at the I percent level. 

'£!Significant at the 5 percent level. 

The 2,4-D + 2,4,5-T amine treatment was e1iJninated from the above analysis 

because it was not represented in an oil-water carrier. Furthermore, the 

2,4-D + 2,4,5-T amine treatment gave conflicting results. In Block I, this 

treatment resulted in almost a 50 percent kill of the sprout clumps that 

originated from stumps; in Block II, only a 4 percent kill. Within a few 

minutes after the completion of spray-ingof the amine plot in Block II, it was 

drenched by a heavy downpour. This may have been the reason for the poor 

kill. 

The 2,4-D + 2,4,5-T amine treatment in Block I resulted in a 63 percent 

kill of chestnut oak--considerably higher than that of red maple or of the 

other oaks. Also, since only one year has elapsed since spraying, this treatment 

may still possibly prove to be quite effective in late-season spraying 

of oak b~sh, especially chestnut oak. 

. Discussions and Conclusions 

The results of this analysis, although based on only one-year's 

observations definitely show the value of adding oil to the water carrier 

when spraying woody brush with 2,4-D + 2,4,5-T esters or 2,4,5-T propionic 

during the late S\Uilm.er. This is especially true where the oaks make up a 

large proportion of the sprout clumps,· since at this time of the year they 

are more resistant to the chemicals than are the red maple clumps. 

It is perhaps misleading to attribute all the difference to the adding 

of oil since the technique of application also differed. However, the stemfoliage 

technique is customarily used with a water carrier, and the sanibasal, 

with an oil-water carrier. As long as this practice is followed, it 

is not necessary from a practical viewpoint to isolate the exact cause of the 

better performance.

206. 

Percent 

Oaks 

100- 

80- 

60- 

40- 

20- 

0- 

'- ....1 

,- __ I 

r--' 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

! I 

L_-l 

_. '-:-:·'-1 

, 

I 

I 

I 

I 

I 

I 

I 

I, 

1--'-4 

Water 

Oil-water 

Water 

Oil-water 

D + T EfJters 

2,4,5-TP 

100- ,---j 

I I 

80- I 

I 

I 

60- I 

I, 

40- 

I 

I 

20- 

~-~ 

I 

, I 

I 

I 

0- '-_.J 1..,_ .-1 

Water 

D + T Mers 

Oil-water 

Red Maple 

r-, 

I I 

I , 

t I 

t I 

1 I 

I , 

l-_.J 

Water 

2,4,5-TP 

'--I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

,-_.-, 

Oil-water 

Figure 1. Percent kill by species, carrier, and chemical for 

sprout clumps of stump origin 1 year following spraying.

207. 

There are a number of interesting points outside the scope of this 

exper:iment that warrant investigation and discussion. For example, what is 

the lowest concentration of 2,4-D + 2,4,5-T esters or 2,4,5-T propionic in 

an oil-water carrier that will consistent~ give good results? Also, what is 

the smallest proportion of oil in the oil-water carrier that will still insure 

good penetration? Should the concentration of chemical and the proportion of 

oil be varied depending upon how late in the growing season the spraying is 

being done? Also large~ left unanswered in this study is the comparative 

value of 2,4-D + 2,4,5-T amine as a late-summer spray. 

There are, of course, other possible solutions to this problem of 

seasonal variation in effectiveness of chemical spraying. For example, the 

use of chemicals in an oil carrier and applied as a basal spray is a proven 

method of killing trees during all seasons of the year. However, in dense 

brush conditions, this method is usually too expensive to obtain satisfactory 

control. 

Perhaps the ideal solution would be to develop a chemical that would be 

effective in a water ~ier even late in the growing season. This would 

eliminate the added expense and inconvenience of using oil. Considerable 

work has already been done along this line and such chemicals may soon be on 

the market. 

Literature 

Cited 

(1) Byrnes, W. R., W. C. Bramble, and R. J. Hutnik. 1958. Effect of volume 

of spray upon topkill and resurge of oak-maple brush. Proc. 12th 

Ann. Meeting Northeastern Weed Control Oonf', pp, 2,30-2,38. 

(2) Research Coordinating Committee of the Northeastern Weed Control Conference. 

1958. Report on WoodyPlants. Supplement to the Proc. 12th 

Ann. Meeting NEW::C. pp. 65-71. 

(,3) Wiltse, M. G., R. L. Dolton, H. C. Ferguson, and W. R. Rossman. 1958. 

Comparisons of commercial herbicides for brush control on power 

line rights-of-way. Proe , 12th Ann. Meeting NEWCC. pp , 201-212.

208. 

A NEWAPPROACHTO BRUSHCONTROL 

P. L. Poulos and W. I. Boyd 

Grasselli Chemicals Department 

]):.1. du Pont de Nemours & Co., Inc~ 

Northeast Weed Control Conference 

New York, N.Y. 

January 7-9, 1959 

Early in our experience with the substituted ureas, it 

became eVident that they might be very effeetive, in relatively 

small dosages, for the control of woody plants. Some initial work 

in the Northeast with monuron, diuron and fenuron for thiS use was 

reported by W. I. Boyd at the Northeast Weed Control Conference in 

1958. It is the purpose of this paper to report further progress 

and the present commercial status of formulations and methods of 

application to control woody plants. 

In the spring of 1955, "Telvar" monuron weed killer was 

registered for chemical control of certain species of trees and 

brush, in drainage' ditches, utility rights-of-way and along railroads. 

The recommended method of use is to prepare a suspension 

of one-eighth to one-quarter pound of "Telvar" per gallon of 

water, and spray this in·a cireular band about a foot away from 

the base of eaeh plant. 

The next commercial registration, in 1957, was for broadcasting 

a 25 per cent peileted formulation of fenuron at the rate 

of 16 pounds of pellets peraore, to control post oak, blackjack 

oak, and winged elm on potential grazing lands in Texas. This 

resulted from several years of cooperative experimental work 

between the Texas Agricultural Experiment Station and the Du Pont 

Company. 

This registration for fenuron was extended to a larger 

number of species in northeastern areas largely as a result of the 

work reported at the Northeast Weed Control Conference last year. 

Currently as a result of field trials in 14 states, we expeet our 

1959 recommendations will be for control of 22 species of woody 

plants. 

Test areas established in May, 1956, along lines owned 

by the Worcester County Electric Company, were rated in July, 1957 

and again in 1958. In these plots, where dry mixture and experimental 

pellet formulations of monuron and fenuron were applied, 

all of the treated woody plants in the plots showed pronounced 

to very severe herbicidal effects in 1957. Substantial increases 

in kill were noted onthese plots this year. (Chart I) Species

which were distributed uniformly through these plots included oak, 

maple, birch, wild cherry, pine, poplar, shad, and hazel. 

Additional tests at substantially reduced rates were 

established in 1957. Results were closely related to the amount 

of chemical applied per brush cluster, regardless of whether a dry 

mixture, slurry or pellet formulation was used. 

Further trials have been conducted to determine practical 

commercial dosage and timing for spot treatment With both monuron 

and fenuron wettable powders andfenuron pellets under various 

commonnortheastern conditions. 

209. 

Evaluation of the spot treatment trials established in 

1956 and scored in both 1957 and 1958 indicates that results depend 

almost entirely on getting an adequate amount of chemical concentrated 

at the base of each cluster. This is one to four grams of 

active material per cluster. One teaspoon of 25 percent fenuron 

pellets provides 1.13 grams of active fenuron, and there are about 

100 teaspoons per pound of pellets. Slurry mixtures of the wettable 

powders seem to offer a good deal of promise, but techniques of 

applying accurate spot dosages still have to be worked out. 

Since fenuron is more soluble than monuron, it is faster 

acting and is, therefore, preferred for commercial use. Thus, 

fenuron, rather than monuron, has been marketed in a pellet formulation 

for control of woody brush. The 25 per cent pellet formulation 

of fenuron now available as "Dybar" fenuron weed and brush 

killer is easy to use and has given good results in both spot 

treatments and broadcast applications. In spot treatment rates as 

low as one teaspoon per brush cluster have given favorable results. 

The label recommendations for use of "Dybar" fenuron 

pellets are as follows: 

For spot treatment in sparse stands of brush, scatter one 

tablespoonful on the ground to cover an area of one-half to one 

square foot at the base of each brush cluster. 

For spot treatment in dense stands of brush, apply one 

teaspoonful every three feet in a grid pattern in the brush area. 

For broadcast application, apply at rates of 50 to 75 

pounds per acre by hand or With mechanical broadcasters. 

These applications may be made any time of year, but best 

results may be expected from late winter or early spring application. 

Experimental 

Data 

These recommendations are based on data covering control 

of fourteen commonspecies of brush obtained in Alabama, Kentucky,

210. 

Maryland, Massachusetts, New Jersey, NewYork, North Carolina, 

Pennsylvania, and Virginia. Early observations in Massachusetts 

for one and two years (Chart I) after treatment have been confirmed 

in a considerable number of ,other trials established last year and 

this year, and observations will continue. Species which have been 

successfully controlled in these trials include American chestnut, 

birch, wild cherry, elm, hazel, hackberry, hickory, locust, maple, 

oak, pine, poplar, shad, and Willow. 

In spot treatment, the brush population naturally is the 

major factor in determining the amount of material required per 

acre. The 'brush population in experiments leading to the commercial 

recommendations for fenuron showed considerable variation, ranging 

from 1,280 clusters per acre up to 14,360, With an average population 

between 2,000 and 4,000 .. (The term cluster is used to designate 

all stems of a single woody plant.) 

Of partiCUlar interest are the preliminary results of a 

Maryland test of "Dybar" fenuron pellets, using a centrifugal grass 

seeder. (Table I) This test was established on a recently cutover 

area of black locust. Three months after treatment, there was 

no evidence of sprouting wherl;! "Dybar" fenuron weed and brust;l killer 

was applied at rates of 50, 75, and 100 pounds per acre and there 

was significant defoliation and reduction in re-sprouting at 25 

pounds per acre. 

Discussion 

Plant response to substituted ureas 1s dependent upon root 

absorption, and was usually eVident in these trials three to six 

weeks after application, depending on the time of year and the 

amount of rainfall. As treated brush died, chlorosis and defoliation 

occurred. 

Susceptible species were killed the year of treatment. 

Oaks and maples re-sprouted several times but were mostly dead 

fourteen months after treatment. All terminal growth stopped as 

soon as first symptoms began to show, usually w1thin a month after 

treatment. Herbicidal effects on some species were noted as long 

as 28 months after treatment, especially where low dosages were 

used. 

In treating rights-of-way, treatment may be applied to the 

edges of the right-of-way where boundaries do not have to be clearly 

defined. But stems or trees at some distance from the point of 

chemical application may be killed if their, roots extend into the 

treated area. 

As there is no Volatility hazard with the substituted 

ureas, they may be used next to sensitive crop land provided the 

roots of desirable plants do not extend into the treated area.

211, 

The effect bn ground cover is limited to the spot actually 

covered by the chemical. This is usually less than one square foot 

with spot application. 

Summary 

Experimental evidence indicates that the pelle ted formulation 

of fenuron meets an important need in industrial brush control 

in the Northeast. The use of pellets eliminates need for moving 

heavy spray equipment over difficult terrain, and is suitable for 

any season of the year, regardless of weather. It is expected 

that commercial experience with "Dybar" fenuron weed and brush 

killer may demonstrate effective control in certain situations at 

somewhat less cost than presently used methods. 

TABLEI 

FENURONBRUSHCONTROL 

Lbs. Pellets 

Lbs. Active 

Per Acre (a) Per Acre .. 

NORTHERNMARYLAND , 1958 

Condition of Black Locust 

8-15-58 ~b~ 

None 

25 

50 

75 

100 

None 

6.25 

12.5 

18.75 

25 

Almost Complete 

99.5 

99.5 

99.5 

roadcas trea ments appl e ay 1 , 

Brush cover, predominantly black locust, had 

recently been cut, and treatments (1000 ·sq. ft. 

per plot) were applied over stubble. Plots were 

bordered by 5 foot buffer strips. 

#######

212. 

Chart I: Two Years Observation Brush Control 

With Dry Mixtures, Fenuron, and Monuron, 

1957 and 1958 

100 

C:::' 1957 

0:-;.:;..;1958 

t; -,'j- - .... ··1 

- -~ 

,,-~_-:"J 

I / / 1 

90 I' " / 

I , I 

, ':,~i 

I 

I 

, , 1/ ..... ,I I 

I 

I, / 

/' 

, I , / I I 

" 

I 

» , , .- r , j "\ I ,- 

I 

, , / 

I 

I , ,-',';- 

80 i ,'" /. , / 

I 

'/ 

/ ,,1 I / I 

, ;

FIJRTHER£TUDIE£ONTHELiSEOF DORl'1.i.NT 

TRE..•TMENTfFORBRJSHCCNTROL.11 

R. E. £ayre and F. s. Chappell 1:.1 

Virginia ..gricul ture Experiment Station 

Blacksburg, Virginia 

213. 

Present planned programs for many commercial companies applying chemicals 

to control woody plants are operational only three to four months of the year. 

By making applications during the season when woody plants are dormant the 

operational programs could be extended to six or eight months of the year, 

thereby making more economical use of equipment and personnel. Such applications 

wouLd eliminate objectional "brown out", which is prevalent when chemicals are 

applied during the warmer luonths. These and other advantages suggested that 

further investigations on the use of dormant season applications were desirable. 

In this investigation, experiments were conducted to compare; (1) sprays 

applied during the dormant season with sprays applied during the growing season; 

(2) concentrations and formulations of chemicals; (3) technical grade chemicals 

with formulated chemicals. 

PROCEDURE 

The experimental areas were located on the power line right-of-ways of 

thei.ppalachain Power Company and the Virginian Railroad Company. The 

elevation of the areas was between approximately 2200 to 2600 ft. The location 

of the sites was on east, west and south facing slopes. These experiments 

~ere selected to better sample the area in which the studies were made. The 

forest climax on the experimental area was oak-hickory in various stages of 

ecological succession. The most abundant species present were chestnut oak and 

red oak. Less abundant species were red maple, black locust, white oak, black 

gum, hickory, sumac, sass~fr8s and pine. 

The plot size was governed by a constant volume of spray material; 25 

gallons for dormant applications and 50 gallons for foliage applications. 

Both volumes covered about the same areas, ranging from one-fourth to onefifteenth 

of an acre depending on stem density. 

Stem counts of the entire plots were taken at the time of application 

and again at the end of the next full growing Season. The species composition, 

abundance of species, number of each species, number of stem resprouts, and 

number of root 

aerial portion 

resprouts were noted and recorded. Spray applications to the 

of the plant is referred to as stem broadcast and spray 

application to the lower l~ inches of the plant is referred to as broadcast 

basal. 

1/ These studies Were supported by research grants from the Appalachian 

Power Company, The Bartlett Research Laboratories and The :..mchemProdue ts, Inc. 

2/ Graduate Research .ssistant on Educational Lease from the F. ~~. Bartlett 

Tree Expert Company and Plant Physiologist.

214. 

Top kill in all instances refers to complete killing of all parts of the plant 

above the ground level. Resprouting refers to the number of sprouts growing 

from the root system and from the root crown to a point six inches above the 

ground level. 

T,IBLEI 

Fall and SummerTreatments. Top kill of original plants 

and resprouting from the roots one growing season after 

treatments. All treaQnent applications are stem broadcast 

unless othen~ise indicated. Stem counts were taken 

in ocecber , 1958. 

P~RCENT TOPKILL PERCENTRESPROUTING 

Treatm",nt 

F..ll (a~;?lied 1"d1, .l~57) 

I;;:: :iliGTech. T. in oii. 

4f: .JiG Tech. O&Tin oil 

~# AHGTech. T. in oil 

Locust 

Locust 

Sumac 

f,umuc 

Oaks Sass. uthers Oaks Sass. uthers 

99.54 98.86 100.00 10.24 98.92 14.61 

98.36 90.25 9~.43 10.28 116.49 24.61 

97.99 98.28 98.75 8.15 91.79 7.S7 

9g.16 99.77 98.67 11.23 131.20 

:.,;; .JiG Formulated T in oil 

: if JIG Formulated Dc.T1n oil 

99.86 99.57 99.97 12.85 147.74 

99.86 99.78 58.49 11.93 105.92 

5.16 

18.47 

~# AHGTech. T. in oil 99.17 100.00 99.02 9.85 101.80 

Check (cut) 291.79 54.54 165.06 

~ (applied SUIIII\er,1!:5"1) 

4ft ,JIG For. Df,Twater 69.90 85.03 79.84 18.77 58.63 27.15 

4# .JlG-lO oil-90 water For. Df,T 83.87 94.01 93.49 25.33 33.84 27.85 

6#HG For. O&T- water 73.40 94.24 93.17 24.34 47.81 33.09 

6fiHG-lO oil-90 t·/ater For. O&T 85.56 96.43 95.95 35.05 41.54 34.38 

61.\Amine T 72.61 94.65 90.55 23.26 91.59 16.44 

Q;i .JiG JDine DC;T 59.71 95.34 86.74 32.37 91.24 22.87 

6# JiG T. Prop. 80.54 91./5 94.32 13.44 161.67 23.59 

8# :JiG ~Ta 82.17 93.26 82.32 21.79 80.96 24.01 

l2~ ABG~Th 88.33 94.15 82.05 13.25 73.11 18.95 

8.67

TABLEII 

Winter and Spring Treatments. Top kill of original 

plants and resprouting from the roots one growing 

season after treatments. All treatment applications 

are stem broadcast unless otherwise indicated. 

Stem counts were taken in October, 1958. 

215. 

Percent Top Kill Percent Resprouting 

Locust 

Locust 

Sumac 

Sumac 

Treatment Oaks Sass. Others oaks Sass. Others 

Winter (applied Winter 1958) 

~HG Tech. T. in oil 97.09 99.85 99.91 20.43 74.16 19.16 

4# AHGTech. D&Tin oil 99.73· 100.00 99.28 18.71 97.38 25.72 

8# AHGTech. T. in oil 100.00 00.00 99.59 7.61 17.36 9.21 

8#AID Tech. D&Tin oil 100.00 00.00 100.00 8.45 42.56 10.83 

8#AHGTech. T. in oil (B) 100.00 00.00 100.00 19.18 34.68 24.04 

8#AHGTech. D&Tin oil (B) 100.00 99.48 100.00 6.11 74.50 19.90 

Check (Stems Cut) 291079 154.54 165.06 

SP[#ng (applied Spring, 1958) 

ABOTech. T. in oil 

99.46 100.00 98.73 66.20 122.88 37.46 

4#AHGTech. D&Tin oil 99.81 leo.co 99.43 ;().78 ;1:74.93 50.78 

8#AID Tech. T. in oil 98.77 100.00 99.45 16.11 54.38 15.20 

8#ABOTech. D&Tin oil 99.63 100.00 100.00 28.77 187.57· 25.32 

8#AHGFormulated D&Tin oil 100.00 100.00 99.79 ~.~ 77.67 6.81 

8#ABOTech. T. in oil (B) 98.91 100.00 99.51 13.52 162.01 23.17 

8#AHGTech. D&Tin oil (B) 97.11 99.41 96.88 8.18 51.58 17.58 

12# AID Tech. T. in oil (B) 100.00 99.70 98.92 3.67 "3.99 16.08 

12# AIDFor. D&Tin oil (p) 97.87 100.00 96.63 9.02 09.67 5.58 

Check (Stems Cut) 291.79 54.54 165.06 

(B) - BROADCAST BASAL

216. 

RESULTS,~o 

OISCUSSION 

One season of growth is not enough for conclusive results, but trends may 

be recognized. Summer and fall treatments were not originally set up to be 

compared directly, but segments were separated and analyzed by an analysis of 

variance test at the 5 percent level. The tests were conducted with the 

assumption that the location of the plots had no influence on the results. 

Comparisons between treatments and also between seasons resulted in no significant 

difference. Perusal of the data indicated that the variance of location 

had a greater influence on the results than the treatment. 

Comparative effects of the various concentrations and formulations of 

sprays during the fall and summer seasons are given in Table 1. Top kill of 

original stems for the summer treatments ranged from 70 to 96 percent for all 

species, while top kill for the winter treatments ranged from 9J to 100 percent. 

Resprouting from the roots for summer applications was generally higher than 

resprouting for the fall applications. Both fall and summer treatments showed 

a high degree of resprouting in the sassafras. black locust, and sumac group as 

compared to the oaks and other specie groups. Compar1sons of the technical 

materials during the fall season indicate that 2,4.5-T is superior to a mixture 

of 2.4-0 and 2,4.5-T for controlling resprouting. 

Top kill of original stems for winter and spring treatments as given in 

Table II are comparable to fall treatments. Resprouting in winter treated plots 

was lOI~ in comparision with all other seasons. Inconsistant resprouting between 

treatments were noted in the spring applications. Technical 2,4,5-T resulted 

in better control of resprouts than a mixture of 2.4,5-T and 2,4-0 in both the 

winter and spring treatments. 

SUMMARY 

1. Winter and fall treatments compared favorably with summer treatments. 

2. Technical grade 2,4,5-T controll~d resprouting better than a technical 

grade combination of 2,4,5-T and 2,4-D. 

3. The percentage of resprouting in the sassafras, black locust, ar.d sumac 

group was higher than the percentage of resprouting in all other groups. 

4. A~vantages associated with dormant applications are: (1) the reduction 

of "brown out", which is prevalent when chemicals are applied as a foliage 

spray during the warmer months; (2) the present operational program 

c~ld be extended to 8 or 10 months of the year; (3) cost of appli~ation 

of dormant treatments is about equal to foliage sprays because (a) it 

requires about half the volume (b) it can be applied in less time (c) and 

it requires lever pressures and smallEr hoses and; (4) the possibility 

~f crop damage is decreased.

IBiologi st , Research Division, The Hydro-Electric Pow.n· C.rmmi ~~ i o n 

of Ontario. Toronto. Canada. 

217. 

FURTHERDEVELOPMEN16 IN THECHEMICALCONTROLOF CONIFERS 

J.M. Bennett l 

Coniforous species of woody growth have become a maintenance 

problGm on thousands of acres of utility right~of-way in Canada 

following the selective elimination of deciduous species by 2,4-D 

and 2,4,5-T herbicides. Preliminary results of an experimental 

program designed to find a solution 'to this problem were presented 

~t the 1957 meeting of the NEWCC/l/. The present paper presents 

further observations on this work, the results of an additional 

year's extensive plot work and discusses the selection of R suitable 

trentment for field use. 

Methods and Materials 

A tagged stem plot technique was used whereby each of tho 

forty trees, which constituted a test plot, was marked with a 

numbered metal tag. A few plots contained only twenty trGos. 

Treatments were made with a compressed air knapsack sprayer and 

about two gallons of spray solution were required to spray until 

run off all stems and foliago in each plot. Applications were 

made during each of April, late May, July and October 1955 and 

early May, July and October 1956. These periods of treatment 

can be placed in four categories, based on stage of growth of 

the conifers. (1) Prior to bud break when trees were essentially 

dormant - April 1955 and early May 1956, (2) shortly after bud 

break when new shoot growth was about three inches long - ~~y 

1955, (3) mid summer after shoot elongation virtually completed for 

the season - July 1955 and July 1956 and (4) fall of the year when 

ttees are almost dormant again - October 1955 and October 1956. 

Final observations of the results of the treatments were mado 

during October 1958. For summary purposes no rating WRS given to 

those stems which were not completely killed, consequently the 

percentage kills as presented represent a conservative evaluation 

of the treatments. 

The test site was a donse stand of conifers, four to twelve 

feet in height, on a high tension right-of-way near Haliburton, 

Ontario. The species were predominately balsam fir, Abies 

balsamea (L.) Mill., and black spruce, Picea mariana r-Mi11.) BSP. 

The site was swampy, verging on a sphagnum bog with a few outcroppings 

of sand covered rock.

218. 

~. 

~. 

j. 

The following chemicals were tested during both 1955 and 1956. 

2,2-dichloropropionic acid, sodium salt, 74 per cent acid 

equivalent (dalapon). 

trichloroacetic acid, sodium salt, 79.3 per cent acid 

equivalent (TCA). 

3-(p-chlorophenyl) -l,l-dimethylurea, 80 per cent wettable 

powder, (monuron). 

2-(2,4,5-trichlorophenoxy) propionic acid, propylene glycol 

butyl ether esters (silvex). 

3-amino-l,2,4-triazole, 50 per cent wettable powder, 

(amitrol). 

polychlorinated benzoic acids. Seven formulations were 

tested at one time or another, during the two-year period. 

All were emulsifiable forms of the free acid. These may 

be classed in four groups based on isomer content. 

(a) predominately 2,3,6-trichlorobenzoic acid 

(2,3,6-TBA) (Heyden HC128lWD). 

(b) predominately 2,3,5-trichlorobenzoic acid 

(2,3,5-TBA). l~jor isomer constituents 54 

per cent, 2,3,5-TBA, 16.2 per cent 2,3,6 

TBA, and 12,~ per cent 2,3,5,6-TBA (Hooker 

X80EO and ACP-M-177). 

(c) predominately 2,3,5,6-trichlorobenzoic acid, 

(2,3,5,6-TBA). Major isomer constituents 48 

per cent 2,3,5,6-TBA, 25 per cent 2,3,4,5-TBA 

and 6.5 per cent 2,3,5-TBA (Hooker X~2EO). 

mixed polychlorinated benzoic acids. Major 

isomer constituents 36.4 per cent 2,3,5,6-TBA, 

15.3 per cent 2,3,4,5-TBA, 16.3 per cent 

2,3,5-TBA and 12.3 per cent 2,5-dichlorobenzoic 

acid. (Hooker X33EO, ACP-L-970 and ACP-M-l03A). 

Other chemicals given limited evaluation only in 1956 were: 

maleic hydrazide, diethanolamine salt (~f). 

4-(2,4-dichlorophenoxy) butyric acid, dimethyl amine salt 

(4-(2,4-DB»1 

3-phenyl-l,1-dimethylurea, 80 per cent wettable powder 

(fenuron).

A number of the less effective chemicn1s tested during 1955 

were not included in 1956 studies and are not discussed in this 

report. 

A surfactant (sodium sulphates of mixed long chain alcoholfatty 

acid esters) and a formulation containing a l-to-l mixture 

of 2,4-dichlorophenoxyacetic acid and 2,4,5-trichlorophenoxyacetic 

acid, isooctyl esters, (2,4-D- 2,4,5-T) were combined with certain 

of the treatments during 1956. 

All rates are given in terms of pounds acid equivalent per 

100 imperial gallons (ahg) or active ingredient per 100 imperial 

gallons (ihg). One imperial gallon is equivalent to about 1.2 

American gallons. 

Results 


219. 

The results of treatment with TCA are shown in Figure lAo 

Applicntions during the season of active growth gave satisfactory 

results with about 8 to 14 pound ahg. Concentrations of 7.9 

and 13.8 pounds TCA gave 55 and 95 per cent kill, respectively, 

when applied in late l~y 1955 and 90 and 100 per cent kill when 

applied in July 1955. The higher concentrations used gave a 

correspondingly high degree of kill. In July 1956, applications 

of S~9 and 11.9 pounds resulted in 82 and 85 per cent kill. Lower 

concentrations produced very severe injury and cooplete kill of 

some trees but the injured trees recovered and adequate control 

was not obtained. Treatment before and after the season of active 

growth generally produced a low level of control. The relatively 

high concentration of 41.6 pounds applied in April 1955 resulted 

in only 35 per cent kill and the same rate in October 1955 killed 

only 32 per cent of the conifers. In Nay 1956 treatment with 

34.6 pounds produced 22 per cent kill. The results of treatment 

in October 1956, when applications of 23.9 and 41.6 pounds TCA 

produced kills of 82 and 100 per cent respectively, appear to be 

at variance with the results obtained with the treatment in October 

1955. The explanation for this difference in activity can be 

attributed to the unseasonably warm weather during and following 

the 1956 applications when average of the daily maximum temperature 

for a lO-day period was 62.9F oompared with 4B.3F for 1955. A 

consistent high level of. control of conifers with TCAwas obtained 

only for applications made during the season of active growth and 

only when concentrations were about 14 pounds ahg or higher. 

The pattern of results with da Lapori as shown in Figure IB 

is similar to that ror TCA (Figure lA), except that higfier rates 

of dalapon were required to produce the same results. The control 

with 22.4 pounds of dalapon in late l1ay and JUly 1955, 95 per cent 

kill at both times, corresponds to 95 and 100 per cent kill 

obtained with 13.8 pounds TCA at the Same periods. As with TCA, 

the lower rates of dalapon caused considerable injury and some 

kill but control was inadequate. Treatments in other than the

220. 

season of active growth i.e. treatments in April and October 1955 

and early May 1956, were relatively ineffective. No treatment with 

dalapon Was made in October 1956. 

Figure 1C shows the results obtained with monuron. The initial 

treatments in 1955 resulted in high levels of kill 65, 80, 

100, and 100 per cent at 2.6, 4.6, 8.0 and 13.9 pounds ihg applied 

in May and 95, 100, 100, and 100 per cent with the same treatments 

in July. Results in October 1955 Were satisfactory only at a concentration 

of 13.9 pounds. During 1956 lower rates were used and 

satisfactory control was not obtained. In the limited trial with 

fenuron during 1956 low rates of application were used and results 

were not satisfactory. 4.6 pounds ihg in May produced 42 per cent 

kill and 1.6 pounds ihg in July produced 25 per cent kill. The 

monuron and fenuron were applied as foliage sprays in the same 

manner as the other chemicals in this study. Soil applications 

might be a more satisfactory technique since these materials are 

known to be readily absorbed from the soil by plants. In the test 

plots where the trees were small and close together, the kill was 

highest, probably the action was largely by root absorption and 

with a dense stand of conifers, a greater amount of chemical was 

applied per unit area. 

The results of the treatment With silvex are in Figure 10. 

Concentrations of 3.31, 5.75 and 10.0 pounds produced kills of 

0, 12 and 15 per cent when applied in April, 22, 60 and 75 per 

cent in late May and 77, 97 and 95 per cent kill in July 1955. 

In October 1955, 5.75, 10.0 and 17.4 pounds ahg resulted in 

kills of 0, 20 and 50 per cent. During 1956, 5.75 and 10 pounds 

ahg applied in early May killed 5 and 35 per cent of the conifers 

While 4 and 5 pounds in July produced kills of 15 and 42 per cent. 

These results for JUly are considerably lower than those obtained 

with comparable conce~trat&nas at the same period during 1955. 

No explanation for this difference is known•. The pattern of 

higher kills with treatments made during the growing season also 

holds for si1vex. 

Amitrol produced interesting results but did not give satisfactory 

control at the rates used. The results are shown in 

Figure 2. Only in July 1955, when concentrations of 8.7, 15.1 

and 26.25 pounds ihg produced kills of 35, 57 and 87 per cent, 

did control approach an acceptable level. At all rates some 

effect on the conifers was observed. The terminal growth which 

developed following treatment was chlorotic on nearly all trees. 

At the higher concentrations as much as two or three years growth 

Was devoid of chlorophyll and this growth eventually died. All 

the surviving trees had some apparently healthy foliage and 

appeared to be on the road to recovery When the final observations 

Were made in October 1958. 

.---'

221. 

The results of the various formulations of polychlorinated 

benzoic acids are in Table I. Unfortunately all formulations 

were not tested at tho same time, nor were the same rates used 

with all formulations, consequently a clear picture of the relative 

value of the various materials was not obtained. 2,3,6-TBA, the 

first formulation tested, gave outstanding results at the rates 

tested during the growing season. Concentrations of 5.75, 10.0, 

17. 4 and 30.2 pounds ahg produced kills of 92, 100, 100, and 100 

per cent re~pectively for a late May treatment and 100 per cent 

kill at all rates in July. Treatment in October was less effective 

with kills of 12, 10 and 20 per cent resulting from applications 

of 3.31, 5.75 and 10.0 pounds ahg. The following year when 

2,3,5-TBA was evaluated, lower rates were used and results were not 

too encouraging with 5 pounds ahg in July resulting in kills of 

15 and 35 per cent for two formulations. Ten pounds applied in 

October 1956 gave a 70 per cent kill. The 2,3,5,6-TBA when applied 

in July 1956 was more effective than the 2,3,5-TBA with kills of 

2~, 70 and 70 per cent resulting from treatment with 3,4 and 5 

pounds ahg respectively. An October 1955 treatment with 2,3,5,6 

TBAat 10 pounds ahg killed 47 per cent of the conifers. The 

mixed isomers of polychlorinated benzoic acids applied at concentrations 

of 3,4 and 5 pounds in July 1956 gave kills of 45, 25 

and 55 per cent for one formulation and 45, 70 and 90 per cent 

for another. This difference in results with formulations of 

the same isomer ratio is as great as the difference between the 

results with the formulations with different isomer contents 

or ratios and tends to confuee an already confused picture. However, 

one formulation of each of 2,3, 5-TBA, 2,3,5 ,6-TBA and mixed 

isomers from the same source and presumably of the same nature 

with the exception of the isomers, Was evaluated at the same time 

during July 1956. On the basis of the results of these tests 

2,3,5,6-TBA Was tho most effective of the three, 2,3,5-TBA was the 

least effective and the mixed isomer formulation Was intermediate 

between the two in effectiveness. 

MHapplied at concentrations of 5.75, 9.2 and 17.4 ihg in 

early May 1956, the only time of treatment, had no toxic effect 

on conifers. There was some indication that shoot development 

was delayed and that the terminal growth was reduced, however, 

no measurements were made. . 

4-(2,4-DB) at 5 and 10 pounds ahg in JUly 1956 caused considerable 

injury but no complete kill. On some trees the top 

50 per cent was killed while on others the terminal shoot was 

simply curled and defoliated. At the final observation period 

new healthy foliage was present on all trees. 

The effect of the addition of a surfRotant, at 0.02 per cent 

by volume, an,d of 2,4-D ~ 2,4,5-T at 3 pounds ahg to sprays of 

TCAis shown in Figure 3A and to sprays of dalapon in Figure 3B. 

With sprays of TCAthe surfactant has enhanoed the kill for treatment 

during both early May and July 1956, but partiCUlarly in July

222. 

when TCAalone at 4 and 6 pounds produced kills of 17 and 30 per 

cent, vmereas with the surfactant kills of 42 and 85 per cent 

resulted from the same rates. Corresponding figures for the addition 

of 2,4-D - 2,4,5-T are 74 and 84 per cent kill. Part of 

this effect of the 2,4-D - 2,4,5-T may be due to the surfactant 

in the formulation of this herbicide. With dalapon the addition 

of the surfactant increased the kill obtained for the early May 

treatment but a lower kill resulted when the surfactant was 

added in JUly. The addition of 2,4-D- 2,4,5-T in July also gave 

conflicting results with a marked increase in activity resulting 

when added to the 11.1 rate but a decrease in activity when added 

to l3-pound rate. Perhaps the explanation for these inconsistent 

results was imcompatability of materials used, and results with 

other surfactants might be more rewarding. 

Summary of Ex~erimental 

Results 

Over a two-year period several chemicals were evaluated in 

plot trials for control of conifers. The results may be summarized 

as follows: 

Range of Concen- 

Chemical trations Tested Control Obta~ 

TCA 4 to 41.6 Excellent at 8 to 16 

Dalapon 4.25 to 38.8 Excellent at 15 to 25 

Monuron 0~8 to 13.9 Variable, promising at 

Silvex 3.3 to 10 Variable, promising at ~ to to 8 

10 

Amitrol 2.9 to 26.2 Promising at 26.1 

Polychlorinated 

Benzoic Acids 3 to 30.2 Variable, promising at 4 to 8 

Fenuron 0.8 to 4.6 Ineffective at rates tested 

MH 5.75 to 17.4 Ineffective at rates tested 

4-(2,4-DB) 5 to 10 Ineffective at rates tested 

Except at very high concentrations none of these chemicals 

was effective for control of conifers when applied other than 

during the growing season. 

Field Trials and General Observations 

From the results of these experiments it is evident that 

there are several chemicals which, when applied as aqueous foliagn 

sprays during the season of active growth, are effective for the 

control of conifers. The choico of a material for extensive use 

depends on such factors as cost, hazards in use, ease of application, 

corrosiveness to eqUipment and effect on other vogetation. 

Other things being equal, the most important single factor other 

than effectiveness is cost. Field trials using several of the

223. 

chemicals tested in plot work, have been conducted to aid in the 

selection of a material for use in conifer control operations in 

Ontario Hydro. In these trials TCAhas given the most consistent 

results and has been the most economical material to use. More 

than 3,000 acres have been successfully treatod during the past 

two years using TCAat concentrations between 10 and 20 pounds 

ahg. This usage has afforded an opportunity to evaluate some of 

the characteristics and effects of sprays of TCAas well as some 

of the factors which influence effectiveness. 

TCAis relatively non-toxic to warm blooded animals and 

presents no hazard from thef·:standpoint of' acute to:ltrc'ity. It is 

irritating to the skin and eyes if used without caution. The 

skin on the hands of some spray operators who used TCAfor prolonged 

periods, became red and peeled off. Although this was 

not painful, it did cause concern. mainly from the standpoint 

of appearance. The use of gloves can overcome this problem. No 

fire hazard exists with TCAitself and the dead conifers on the 

right-of-way are no greater a potential hazard than if they were 

cut. In any case, the danger is temporary as the needles soon 

drop and the trees eventually decay. Since TCAis a grass killer 

there was concern about possible destruction of the grass cover 

on right-of-ways. However, experience has shown that only temporary 

and localized injury results from the field use of TCA 

for conifer control. 

The ideal conifer control technique is one which could be 

used to control deciduous as well as coniferous woody growth. 

Combinations of TCAwith 2.4-D - 2,4.5-T have been applied on a 

large scale in addition to the small plots. Control of conifers 

was excellent. Although it has not been too clearly established 

whether the TCAinterferes with the action of 2,4-D - 2,4,5-T on 

deciduous species, indications from the field work are that with 

the mixture. satisfactory control can be obtained of tho deciduous 

species usually associated with conifers. namely poplar, birch, 

willow and tag alder. 

Corrosiveness to eqUipment is a major concern in the extensive 

use of TCA. In a series of laboratory tests, solutions of 

TCAattacked magnesiumnndhluminum severely and st~G1 moderately. 

The use of protective coatings and frequent washing of the eqUipment 

can minimize this hazard. Formulations of TeA containing a 

corrosion inhibitor may be obtained at a premium price; laboratory 

tests with such a formulation demonstrated that with the possible 

exception of magnesium. corrosion was satisfactorily inhibited. 

No corrosion hazard to conductors and tower steel is anticipated, 

because of the limited exposure and the washing effect of subsequent 

rains. ..

224. 

Differences in the susceptibility of various species to _/ 

control by chemicals became evident in these studies. Spruce 

is most resistant followed closely by balsam fir. Any treatment 

which will control these two species appears to be effective for 

other problem species, e. g. , Jack pine, white cedar and white 

pine. For all species the smaller the tree the easier it is to 

kill. Very thorough coverage of each tree is required to give 

complete kill. If the lower branches are not well sprayed they 

may survive and eventually produce a new tree. The weather has 

considerable influence on the rapidity of action of the chemicals, 

particularly TCA. On bright, sunny days brown-off of the foliage 

may occur in a few hours, whereas in cool, d:ull weather several 

days may elapse before a noticeable effec~thas taken place. 

Aircraft 

Application 

Application of chemicals from aircraft, including helicopters, 

has proved to be practical for control of deciduous brush and would 

be a boon in conifer control operations which, for the most part, 

are required in remote areas of the north. Limited trials have 

been conducted with TCA and polychlorinated benzoic acid formulations, 

but a satisfactory tr~atment h~s not yet been evolved. 

Because of the corrosiveness of TCA to aluminum and magnesium, 

and the prevalence of these materials in .a.ircraft structures, an 

inhibited formulation of TCAwas used for this work. 

Dormant-Season 

Control 

As already mentioned none of the chemicals applied in a water 

carrier was effective for conifer control except during the growing 

season. Earlier work indicated that an oil carrier was more 

effective during the early spring and fall, no doubt due largely 

to the toxic effect of the oil, and 2,4-D ~nd 2,4,5-T in an oil 

carrier can be used for conifer at these times. This technique 

has its limitations, but is quite useful under certain circumstances. 

In areas where resistant species of hardwoods, especially 

maple, have survived the standard herbicidal treatment of 

2,4-D - 2,4,5-T in a water carrier, abasnl· spray with an oil 

carrier is now being used. Conifers growing in the same sections 

of the right-of-way can be killed by using the same mixture as an 

over-all spray. Thus, a clean-up of the brush can be accomplished. 

This work is usually done in the fall of the year, a time when 

much of the equipment is often idle. 

REFERENCE 

/1/ Bennett, J.M., Chemical Control of Conifers on Utility Rightof-Way, 

Proc. 11th Annual NEWCC,p 329-35, January 9, 1957.

( 

.I 

.I 

100 

--,-.- 

..- 

80 

., 

: " 

.JULV 1955 

.'l:_--._ 

",' 

i 

./ 

/ v--t 

i 

~,.Io 

... y'" 

... :; 

, , 

·to 

r 0'" 

f 

OU 

,,,,~e, 

/'EARLY MAY 1956 

Z.5 

/ 

" 

"~ - 

Z.5 

5.0 

5.0 

.~ . 

·r., 

~ 40 .; 

0 , : 

0: . , 

.. 

Q. 

i~ 

-c 

:> 

zo .. 

C 

MONURON 

7.5 10.0 12.5 15.0 

CONCENTRATION IL.B IHG) 

-t 

~v_ 

-r- 

!_. 

,.IoV;-t •• 

Jr JULY I.' 

.... LATE MAY 1955 

D 

,,,,.,'0 

SILVEX 

cf:-~?e 

, . 

APRIL 1955 

7.5 10.0 12.5 '5.0 

CONCENTRATION [LB AHG] 

~f' ,~s/-' 

r" 

17.5 

17.5 

FIGURE I PERCENTAGE KILL OF CONIFERS OBTAINED WITH AOOEOUS FOLIAGE SPRAYS 

OF VARIOUS CONCENTRATIONS OF TCA, r.;ALAPON, MONURON AND SILVEX 

AT DIFFERENT PERIODS OF APPLICATION 

I\) 

I\) 

VI

) ) 

'00 

oJ 

oJ 

~ 

.. 

e 

80 

60 -I 

~ 

Z 40 

Id 

U 

0:.. 

II. 

20 

01-----,-----1-- - 

o 2.5 5 

/ 

/ 

(/ 

/ 

.-- 

,/ 

J\J\..o"'l__\9~!J__· 

-- 

\9'>-:' 

t/lp.-( • - 

V""-!' - - 

__ X- APR'''=" 19~5_. - 

", -·J'-'---C:---:----l----·--r-~·.: i-~· .._._~, -------. 

7.S 10 12.5 15 17.5 20 20/.S 

CONCENTRATION (LB IHGI 

2~ 

•• 

'Y' 

I 

27.5 

,oo-! 

eo 

oJ 

oJ 

X 60. 

Id 

I!I 

~ 

~ 40-' 

U ! 

0: 

Id 

II. 

zo-: 

~ 

• 0 

'-0 (\/ 

(\/FIGURE 3 

FIGURE 2 PERCENTAGE KILL OF CONIFERS OBTAINED WITH AOUEOUS FOLIAGE SFRAYS 

OF VARIOUS CONCENTRATIONS OF AMITROL AT DIFFERENT PERIODS OF APPLICATION 

f 

.' 

.,1 

.,; 

;1 

e~ 

TeA 

i 

I 

,/ 

/' 

i 

TCA 

_ 

.....- -l( TREATED 

r .JULY 1956 

"'X 

TREATED EARLV .• ~ 

M~19~ /x ~G~- 

'l(. - ---i( -'" vP' 

~ __ 

- 

10 

+ O-T 

A 

TCA 

O-T •• 2,4-0 - 2,4,S-T [I. I) 

15 

USED AT 3 LB AHG 

55 ... SURFACTANT USED 

AT 0.02 PER CENT 

'c- -" 

-, 

20 

, 

25 

CONCENTRATION (LB AHG] 

30 

35 

100 -; 

o~~ - 

TREATED 

Il I : EARL.Y 

.x: ...... 0.- 

yoJ)/ / 

MAV 1956 

o , 

«: 

---,-------!-----,- -----;- ._- 

80- 

.J oJ 

~ , 

III 60-1 

e « I- z 

III 40 

U 

a: 

Id 

II. 

20 _I 

o 1--_.-- 

DALAPON 

/' 

,,- ,," 

, . 

r OAL.APON 

DALAPON 

PERCENTAGE KILL OF GCNIFERS OBTAINEfJ WITH A'-'UEOUS FOLIAGE SPRAYS OF TeA ANiJ IJALAPON, 

.'\LCNE i\Nu IN COIVEINl~,TION "11TH A SURFA::TANT i'.NJ "!ITH 2,4-0 - 2,4,5-T 

o 

+ D-T 

J< 

·Ii 

'\ 

TREATED - / ~ Jr'" 

JULY 195~_o'" I ' 

B 

10 15 ZO 25 

CONCENTRATION [LB AHGJ 

-~ CALAPON + 55 

D-T .. 2,4-0 - 2,4,S-T [1.1] 

USED AT 3 L.S AHG 

55... SURFACTANT USED 

AT 0.02 PER CENT 

I 

30 

IC 

DALAPON 

35

( 

TABLEI 

PerCent Kill of Conifers with Aqueous Foliage Sprays of Various Concentrations 

o£ Seven Formulations of Polychlorinated Benzoic Acids Tested over a Two-Year Period 

Concentration (lb ahg) 

Isomer. Formulation Treatment Date 3:6 3.31"bQ 5.0 5.75 10~0 17.4 30.2 

2,3,6-TBA 

HC128lWD 

" 

If 

M9y , 

1955 

July, 1955 

Oct ,", 1955 

12 

92 100 

100 100 

2,3;5 ..TI3A 

Hooker X8(}EO 

July, 1956 

:1.0 

ACP-fo';-l77 . 

I' " 

July, 1956 

Oct., 1956' 

20' 

,, 3 , 5, 6-TBA 

Hooker X42EO 

Oct ; , 1955 

15 

" 

" 

July, 1956 

25 

lixed isomers 

Hooker X33EO 

July, 1956 

45 

ACP-L-970 

Oct , , 1955 

2 

" " ;, 

May, 1956 

5 

ACP-M-l03A 

., ;, " 

July, 1956 

Oct , , 1956 

45

228. 

CHEMICALBRUSHCONTROL 

ON PUBLIC WATERSHEDSAND SUPPLY LINES 

Archie W. Paine 

General Superintendent, Sources of Supply 

Metropolitan District Water Bureau 

Hartford, Connecticut 

PUblic water supply in the Hartford metropolitan area has 

over 100 years of history behind it -- 103 to be exact -- but at the 

end of 98 years we were still depending on axes and scythes to clear 

brush around the shorelines of our reservoirs. At the present time 

we have two functioning reservoirs and a third one being developed, 

and our present consuming population is about 350,000 people. 

In the watershed area, the district owns approximately 

28,000 acres, a great deal of it in woodland. Modern forest conservation 

methods are used in the care of this timberland, with 

selective cuttings as trees in a given area reach maturity. Considerable 

reforestation work has been done adjacent to reservoirs, 

where we have replaced the natural growth of broadleaved hardwoods 

with conifers. By surrounding our reservoirs with conifers, we 

prevent the accumulation of leaves in the water, where they might 

affect the flavor and color, and could interfere with the operation 

of valves and pipelines. 

Between this conifer screen and the waterline is an area 

varying from a few feet up to perhaps 150 feet, which we call free 

board. This is the leeway between the waterline of the full reservoir 

and the edge of the forest planting. This free-board area 

gives us a margin for the rise of high water, and also gives us 

access around the edge of the reservoir when we need it. 

We can't let brush grow there because we'd get right into 

the problem of leaves in the water again. 

Then of course we have the usual reasons for clearing 

brush that are common to any operating area --. whether it's a powerline 

right-of-way, a timber road, or a gas pipeline. These all add 

up to providing greater safety and more efficient and economical 

working conditions for the crews that have to work in the area, 

and elimination of such hazards as poison ivy. 

We have been able to exchange information and recommendations 

with the people responsible for brush control on the utility 

rights of-way running through the watersheds or near them, and this 

has worked out to everyone's advantage. Watershed safety regUla 

tions once left them With no choice but hand-cutting in watershed 

areas. But as chemical methods are approved for our own use, they 

can use them too.

229. 

We are still in the process of developing a program to 

meet our special requirements. First, to give you an idea of the 

size of the job ._- the total shoreline for one reservoir is 11 

miles, while the other reservoir is 30 miles, or a total of 41 miles. 

The free-board area averages 25 feet in width, so we have about 125 

acres of shoreline to keep clear, plus ten miles of pipeline rightof-way 

averaging 75 feet wide -- or about 90 acres of right-of-way 

a total of about 215 acres of land where we have to control brush. 

Briefly, here is what we have accomplished so far: 

up to 1954, we kept a 10-man crew busy from early spring to late 

fall, cutting brush along the shorelines and along the pipeline 

rights-of-way. Now we have one three-man crew doing chemical 

spraying for a few weeks each year, and we have been able to cut 

our summertime temporary roll in half. Furthermore, where we have 

kept comparative cost records, costs of the chemical spraying 

average less than two-thirds the cost of hand-cutting. 

In developing a chemical brush control program for watersheds, 

we have to consider two basic reqUirements. First, the 

chemical has to be approved by the people responsible for the 

purity of the water. Second, the method of application has to be 

practical for the terrain. In areas where you have access roads 

of some kind, of course you can get in with a hydraulic sprayer 

and use long hoses to reach where the sprayer can't go. But some 

parts of the shoreline of our reservoirs are wet most of the time, 

or else they're rugged and rocky. For some of these areas we've 

tried approaching from the water in a boat, and sending men in 

with watering cans to treat the brush. 

None of these methods of application seemed to promise 

the savings we thought we had a right to expect from chemical control. 

So we have taken a leaf out of the fruit-growers' book and 

we're using a mist blower - not a giant orchard sprayer, but a 

little knapsack-style blower that straps on a man's back and runs 

With a gasoline engine. (SHOWSLIDE) This unit weighs about 35 

pounds, and holds 2 1/2 to 2-3/4 gallons of spray. For each 

filling we use eight pounds of a special formulation of "Ammate" 

weed and brush killer, in two gallons of water With an ounce of 

spreader-sticker. This special formUlation is the same as 

"Ammate" X Without the sodium bichromate.' 

This is a simple air-blast unit, so there is no_appreciable 

pressure in the tank. The mist is created by blowing air 

at a velocity of 250 miles an hour through a stream of spray solution. 

The air orifice is 1-3/4 inches, and the orifice for liquid 

is 3/32 inches. At full throttle the unit will give good coverage 

of brush at a distance of 12 to 15 feet from the operator. 

This unit gives partiCUlarly good ooverage of the stems, 

branches, and foliage -. both the upper sides of the leaves and the 

under sides.

230. 

Since this unit applies a fine mist with little runoff, we 

are getting effective coverage with 72 pounds of IIAmmate ll weed and 

brush killer per acre. This is considered to be less than half the 

lIaveragell amount needed. 

Obviously you have to use a completely nonvolatile herbicide 

in this type of equipment because of the application technique. 

Furthermore, you have to use something in watershed areas, anyway, 

that the laboratory will approve. Our laboratory and sanitary 

engineers have given this special formulation of IIAmmate ll a clean 

bill for our program. 

We figure that nine tankfuls with this unit will oover 

an average acre of our brush. Our average aore is about eight feet 

high, with an average diameter of one to two inches - the normal 

regrowth following outting that you get in four or five years in 

Connecticut. 

Average growth includes all oommonNew England species 

birch, maple, oak, hickory, ash, sumac, sassafras, willow, poison 

ivy and cherry. 

Nine tankfuls is only 72 pounds of IIAmmate ll to the acre, 

and some people think this isn't enough to do the job. But this 

slide (SHOWSLIDE) shows how an area looked after the spray had 

begun to take effect. And this one (SHOWSLIDE) shows how the same 

area looked a year later. 

Wehave obviously gotten excellent kill of all the woody 

brush in this area, using just about half as much "Ammate" weed and 

brush killer in the mist blower as we think normally would be used 

in a hydraulic sprayer with spray guns. 

A man operating this mist blower can get into areas where 

it would be just about impossible to drag hoses from a hydraulic 

sprayer. 

The operator refills from 50-gallon drums of pre-mixed 

spray whioh are hauled on a trailer pulled by a wheel-tractor as 

close as possible to the area where he is working. If the mistblower 

is operated continuously at full speed, one filling will 

last 15 to 18 minutes. But it is generally operated at less than 

full speed, and of course, the spray is not being applied continuously, 

so one filling may last from 20 minutes to an hour, 

depending on the size, density and accessibility of the brush. 

The success of this method of brush control, like any 

other in our experience, depends on the spray operator. For this 

kind of work we try to find men among our regular skilled and semiskilled 

crews who seem to have an interest along this line. Then 

we train them not only in the job to be done, but also give them a

231. 

chance to see the results. We may go over the sprayed area with 

them twice during the season of spraying -- once about three weeks 

after application, and again in another six weeks. Then the following 

year we take another look to see whether there has been any 

regrowth, new growth, or skips that will require another treatment. 

We still do some cutting ourselves, and we are still 

experimenting with new ideas and new products. During the past two 

seasons we have treated the surface of every fresh-cut stump of an 

inch in diameter or more with a tablespoon of dry lIAmmatellweed 

and brush killer to kill the roots and prevent resprouting. While 

I know stump treatment is not a new practice in brush control, it's 

new to us, and we feel we have to tryout any practice on a limited 

scale before we adopt it widely. 

I mentioned earlier that we have exchanged information and 

recommendations with others working :Inthe brush control field. Perhaps 

our success with the mist blower may offer others the idea of 

using it. It seems possible that the technique of increasing the 

chemical concentration and using a mist instead of a spray might be 

adapted to a degree to hydraulic sprayers, for areas where they 

can be used. This might be accomplished by simply increasing the 

pump pressure and using spray guns with smaller orifices. Some 

of you who have had considerable experience with hydraulic spraying 

of brush might knew of other approaches that could be tried. 

Just to reiterate the advantages of our application technique you 

use much less chemical, and you get better foliage coverage without 

runoff. 

In one sense, our present program is only a preview of 

what's ahead for us because the new reservoir now under development 

will more than double our watershed area. Meanwhile, if 

present trends continue, there will be more and more reason to 

economize on expense and manpower. in every kind of maintenance 

program. In brush control we will be looking for the longest 

possible control on the lowest possible bUdget. It looks as though 

our present program will probably give us acceptable brush control 

for about four years With one spraying -- and retreatment is generally 

a much smaller project than the original spraying. 

The next thing, of course, will be to work out a schedule 

for our property so that we can get over the land in one cycle 

before it is time to spray again. With such a program, we can 

combine minimum annual budget With maximum labor efflctency in an 

effective brush control program. 

######

232. 

Effect of Simazine t Related Triazine Compounds, 

and Various other Herbicides On 

Native Weeds and Grasses 

James H. Flanagan 

Geigy Agricultural Chemicals 

Simazine (2-chlor-4,6-bis(ethylamino)-s-triazine) was 

synthesized by Gysin and Knusli in the laboratories of J. R. " 

Geigy, S. A., Basle, Switzerland. Experiments in this country 

as well as in Switzerland showed that the compound is an effective 

herbicide, primarily efficient in a pre-emergence 

application. Since the. chemical is taken up by the roots of 

germinating .or" existing plants, adequate moisture is required 

to carry the Simazine to the root zone. The solubility of . 

Simazine in water is only about, ppm so that under conditions 

of light rainfall, the herbicidal action may be quite slo~. 

The following experiments were undertaken to study preand 

post-emergence applications of Simazine and several related 

compounds, alone and combinations of Simazine with commercial" 

herbicides. The plots were laid out in uncultivated areas of 

Westchester and Rockland Counties, New York, having a good 

population of native perennial weeds. 

tests: 

The following triazine compounds were included in the 

Produc"t, " 

G-27692 Simazine 

G-30027 Atrazine 

G-30026 

Chemical Name 

2-chloro-4,6-bis(ethylamino-striazine 

2-chloro-4-isopropylamino-6 

ethylamino-s-triazine 

2-chloro-4-isopropylamino-6-methylamino-s-triazine 

G-31435 Methoxy Propazine 2-methoxy-4,6-bis(lsopropylamlno) 

-s-tria.zine 

G-30044 Methoxy Simazine 2-methoxy-4,6-bis(cthYlamino)-striazine 

G-32293 Methoxy Atrazine 2-methoxy-4-isopropylamino-6-ethylamino-s-triazine

233. 

The four following methods of application were employed in 

the experiments: (1) watering can, (2) back-pack sprayer, (3) 

modified low volume weed sprayer, and (4) Jeep-mounted Chesterford 

Logarithmic Sprayer. 

Test 

No.1 

Simazine, Atrazine and G-30026 were applied to triplicated 

10' x 10' plots on November 10 and 11, 1957 at dosage rates of 

5, 10, 20 and 40 pounds active ingredient per acre. The suspensions 

were applied with a sprinkling can at the rate of about 

1-1/2 gallons per plot. 

No effects of the treatments were noted until the spring 

of 1958. During April and Mayall of the plots were free of 

weeds; however, many dicotyledonous weeds germinated but failed 

to survive. By early June, weed growth was noted on all plots 

receiving the 5 pound per acre treatments. TheG-30026 plots 

were covered with crab grass. Hedge bindweed, horseweed, wild 

carrot and yellow wood sorrel were evident on the Simazine and 

Atrazine plots. In July, these weeds appeared on the Simazine 

plots which received 10 pounds per acre. The Atrazine plots had 

less of these species; however, all plots contained fall panicum 

(Panicum dichotomiflorium) seedlings. 

the 

In October 1958 the following conclusions were drawn from 

plots: 

1. Simazine at 20 and, 40 pounds per acTe maintained complete 

weed control for one year following a fall application. 

2. At rates of 5 and 10 pounds per acre a supplemental 

spring.applicat1on of S1mazine would be necessary to keep all 

weeds controlled. 

3. Atrazine gaverasults comparable to Simazine at all 

rates, possibly more effective at the 10 pound rate , 

. 4. Annual. PanicUin species show Some 10lerance to Atrazine 

and G-30026 and to .alesser extent to Simazlne. 

5. Crabgrass and Pan1cum sp. were the only annual weeds 

to appear in any of the plots. 

Test 

No.2 

On April 22 and 23, 1958, Simazine, 1l.trazine, Methoxy 

Propazine and G-30026 were applied at the rates of 5, 10 and 15 

pounds per acre to 10' x 10' triplicated plots in Rockland 

County. The materials were applied with a watering can at the 

rate of about 1-1/2 gallons per plot. W1nter annual, biennial 

and perennial weeds were present in the plots,.

234. 

EFFECTONWEEDSAT WEEKLYRATINGS 

75 

So 

I 

I 

I 

I 

I 

/' 

I 

/' 

75- 

So 

/ . 

/ 

METHOXYPROPAZINE 

/ 

GROUNDFREEOF WEED~; 

'J-.~-.lks 

I . 

4 

I . 

7 s 

O~sarvations of the test during the season led to the fol~ 

lowing conclusions: 

(1) All four of thes.e ehemfcaLs produced practical seasonal 

control at the 10 and 15 pound dosage rates. 

(2) .l:l.trazine waS faster acting than Simazine or 0-30026 

and controlled tl1esaJ:lle wee,lis as Simazine. The 5 pound rates 

of Simazine and Atrazine.produced satisfactory control, except 

that perennial panicum. grasses were present in the latter. 

All· "losage rates of Atrazine killed the overwintering stages 

of perennial panf.cum spe.eies put failed .to control the germinating 

seeds of these species. The only other weeds. found to be 

tolerant to S~azine and Atrazine were two species of st. John's 

worts, (HypericumPHforatwn ap,1i1L.mutiliwn). Tl1ese early applications 

controlle.d the perennial bluegrasses (.f.Qll sompressa 

and ~ trivialis); control by later applications has been inconclusive 

• 

(3) Methoxy propazine at 10 and 15 pounds per acre produced 

rapid knockdown and controlled all of the weeds mentioned in the 

list of weeds indicated hereafter. Yellow wood sorrel has a considerable 

tolerance to Methoxy Propazine. 

Test 

No.3 

Simazine and Atrazine at dosage rates of 5 and 10 pounds per 

acre in combinations with the following herbicides were applied 

to 100 square foot plots with a low volume and.a back-pack sprayer 

on May 26, 27 and 28, 1958: ...

Chemical 

lunino Triazole 

Dalapon 

Polychlorobenzoic 

TCA 

MCPA 

TCA- 2,4-D 

Dalapon - MCPA 

and lbs./acre 

acid 

~ 

8 

100 

2 

100 - 2 

40 - 2 

235. 

Two weeks after application the combinations containing 

TCAproduced the fastest knoekdown with the Dalapon combinations 

second. The addition of 2,4-D to TCAand Dalapon combinations 

did not increase initial knockdown. Amino triazole was somewhat 

beneficial over Simazine alone at the 5 pound per acre level, but 

did not produce quick knockdown. 

Four weeks after application, Atrazine alone and Atrazine 

with other indicated compounds were equal to or better than the 

additives alone or in combination with Simazine. 

Combinations of Simazine and Atrazine With Other Herbicides 

Test No.3, Applied May 26-28, 1958 

Percent Leaf Burn 

A. S 

t i 

I' m 

a a 

z 

i 

n 

e 

z 

i 

n 

e 

A S A S 

t i t i 

r m I' m 

a a A a a A 

z z 1 z z 1 

i i 1'\ i i 0 

n n n n n n 

e e e e e e 

Amino triazole 5# 

Dalapon 40# 

2,4-D 2# 

Dalapon 40# 

+ 2,4-D 2# 

Benzac 8# 

Triazine alone 

,Triazine alt"ne 

,TCA 100# 

MCPA 2# 

2,4-D 2# + TeA 100#-~"=T~P:.r-~~~~~~4-Jl~~~~~~~t 

Dalapon 40# . 

+ MCP1.. 2# 0 

Triazine alone -!3-'=5-6-70~'~~~~~~~-6-4r4-~:H-..J.:::.~~~~i;!,+.~~1 

(Sym - typical 

symptoms) 

The plots were rated at frequent intervals during the remainder 

of the se ason from which the f'nllnw1n17 ('(m"1,,.,1,m., ""n hA

236. 

(1) dtrazine alone after 4 weeks produced results equal tv 

or better than any of the combinations and maintained 95% to 100% 

control for the entire season. 

(2) Atrazine was superior to Simazine when applied postemergence 

• ' 

(3) All combinations increased the knockdown and overall 

performance of Simazine, particularlY at the 5 pound dosage level. 

The increased performance was more pronounced in combination with 

TCA. Results of subsequent tests indicated that a desage rate 

less than 100 pounds of TCAwas adequate in combination with 

Simazine at a dosage level of 5 pounds. 

(5) No annual broadleaf weeds or annual grasses appeared 

in any of the combination plots or with Simazine or Atrazine 

alone. Both Simazine and Atrazine controlled seedling wild garlic 

but not mature bulbs. The only species to make new growth in 

the fall were perennial blue grasses. 

Test 

No.4 

On June 13, two hundred square foot plots were treated with 

i",trazine and Simazine, at 5, 10, 15 pounds per acre. The chemicals 

were applied with a back-pack sprayer using approximately 200 

gallons per acre to weeds 12 to 24 inches high. Within three 

weeks, Atrazine caused 100% burn to leaves and 80% burn to stems 

of all species present in the plots treated with the 15 pound 

rate; at 10 pounds per acre rate, 70% to 80% of the leaves were 

burned and severe chlorosis occurred to terminal growth. Corresponding 

rates of Simazine produced symptoms on most species and 

leaf burn on certain species, namely; ox-eye daisy, black-eyed 

susan, red clover and sweet clover. It was confirmed from further 

observations that the burn produced by Atrazine resulted in 

complete death of all species, the only variable being the speed 

of action. 

Test 

No.5 

~ test ,was applied on June 20 using 15 pounds per acre of 

b,trazine and Simazine on horse tail (EguisetulIl arveng) with a 

back-pack sprayer. Within three weeks the horse tail was completely 

burned in the Atrazine plot; Simazine produced only 

slight burn. Later observations indicated Atrazine had effected 

excellent control while only partial control was given by 

Simazine. 

Test 

No.6 

The foll~wing dosage rates of Simazine and atrazine and 

Hethoxy Propazine were applied with a logarithmi~ sprayer on 

July 1 and July 5, 1958 : ' 

(1) Simazine 40 lbs~/Adecreasing 

(2) atrazine 40 lbs./Adecreasing 

(3) Methoxy Propazine 40 fbs./A,decreasing 

After two weeks, a compar~son between the speed of action 

of Atrazlne at 10 pounds per acre ana',ari application of the sarnA

ate made five weeks earlier indicated that the stage of growth 

is an important factor in the rapidity of knockdown. Early 

blooming species of weeds were affected to the same degree from 

e.ither the early or late application, while the late bloom,1ng 

species , such a's goldenrod; yelJow toad 'fl~:X: and aster, required 

a higher dosage in the ·lateappUcation· togi v'ethEi same amount 

of injury. Rates in excess of 12 pounds produced qUick lmockdown. 

In th~,se PJ.ot~, the onlxweed tOi~urvtve was dande:llon. 

The act;on of Methoxy Propazlnedldnot appear to be affected 

by the stage of growth at rates.inexcessbf 10 pounds 

per acre. The only species 'to .survive were yellow wood sortel 

and a few wild carrots.' ' . ' 

Simazineproduced poor results 11;1these late 8pplicatJons. 

The 40 pounds per acre dosage' ofSimazlne was comparable to 12 

pounds per acre of Atrazine. 

Test 'No. ? 

237. 

During the 'Weekof July 22, Simazine and .t...trazine were combined 

with a series of other herbicides in plots sprayed with the 

logarithmic sprayer. 

Simazine and Atrazine were applied at a constant rate o~ 5 

and 10 pounds per acre and were combined with the following 

materials: . 

1 • 

2. 

3. 

4. 

5. 

Chemical 

Amino triazole 

TCk 

TCA- 

2,4-Damine 

Dalapon 

Dalapon 

2,4-D amine 

2,'~-D amine 

Pounds per Acre. 

Decreasing 

6. 

r c- ", 

Tn addition,the' following materials' were 'applied' alone: 

1• Methoxy Propazine,1 5 pounds pElr aere, de creaf'\ing , 

2. G-:-32293( 20 pounds' per acre, decreasing. 

Before gi vlngconclusi\;nS, it should- 'be'fltated that at the 

time ofapplfeation weeds generally wereh6t ae\tfively growing or 

were in the leveling off stage of growth. 

This test was conducted on an abandoned farm in Rockland 

County, ,NewYork, whi'Ch has been out of pro duction for six years. 

Weed growth consisted of a majority of the weeds mentioned previously 

with goldenrods (Solidago ~.) predominating. The weeds 

at the time of application were 15" to 24" high. Very little

with the TCA combinations and on the l~thoxy propazine plot~ 

within two days after the application. Slight burn wasnoten 

with Atrazine and G-32293 after four days; no rains occurred 

during this period. As a supplement to this test, 200 square 

foot plots were sprayed with Atrazine and Hethoxy Propazine 

with a back pack sprayer using 5, 10, 15 pounds active in 200 

gallons of water per acre. The purpose of the test was to 

compare a back pack sprayer application versus applications With 

conventional low volume sprays. 

Results of the test would indicate the following conclusions: 

(1) TCA combinations again proved the qUickest acting; . 

between 50 and 60 pounds per acre of Teb appeared to be asatisfactory 

dosage rate. 

(2) The activity of Simazine and Atrazine alone was much 

slower when compared with earlier applications. 

. (3) The application of Methoxy Propaz1ne at 15 to 20 p~unds 

per acre active was very effective as a knockdown chemical. -: 

(4) Method of application affected the speed of action:on 

the weeds but not the weed control at the end of the season. 

Summary 

In summarizing the activity of the triazine compounds in 

the above tests, the following conclusions may be stated: 

(1) For maximumresults with Simazine, applications must 

be made before active growth begins and should be applied before 

or during the period of maximumrainfall. If for various reasons 

the time of application is delayed, combinations of various contact 

herbicides with Simazine will partly overcome the growth 

factor. 

(2) Atrazine is definitely more active on emerced weeds 

than Simazine and can be applied later in the season to control 

the same weed species. Rates of 10 pounds pe, acre were found 

to be effective for general weed control. Motthe present time, 

the exact residual nature of Atrazine is unknown; however, it 

did produce seasonal control. 

(3) Methoxy Propaz1ne and Methoxy atrazine domonstrated a 

high degree of foliage toxi,ity. The minimum dosage rate for 

Methoxy Propazine alone 1s 10 PQunds per acre. A sharp decrease 

in activ1ty on perenn1al weeds occurs below th1s rate.

Weeds Controlled by Atrazine, Simazine, 

and Methoxy Propazine 

The following is a list of weeds controlled in the experiments 

conducted in Rockland County, ~ew; York. Weeds not 

controlled are discussed separately in the report of each experiment. 

1 • 

2. 

a: 

5. 

6. 

7. 

8. 

9. 

10. 

11 • 

12. 

13. 

14. 

15'. 

16. 

17. 

18. 

19. 

20. 

21. 

22. 

23. 

24. 

25. 

26. 

27. 

28. 

29. 

30. 

31. 

32. 

33. 

34. 

35. 

36. 

37. 

38. 

39. 

40. 

41. 

42. 

Pasture thistle 

Golden r.ods Sp. 

Ox eye daisy 

Black eye susan 

Narrow leaf plantain 

Broadleaf plantain 

Wild earrot 

Yarrow 

Yellow wood sorrel 

Curled dock 

Burdock 

Prickly lettuce 

Wild lettuce 

Purple stem aster 

Spreading cinquefoil 

SUlfur cinquefoil 

Yellow hawk weed 

Yellow toad flax 

Commonspeedwell 

Stork bill 

Tall butter cups 

Daisy fleabane 

Horse weed 

Horse tail 

Will parsnip 

Yellow mustards 

Timothy 

Quack grass 

Slender rush 

Orchard grass 

Nible will 

Oat grass 

Hop sedge 

Crab grass 

Broom sedge 

Yellow rocket 

Commonmullein 

Purple meadow rue 

Evening primrose 

Wild strawberry 

Crane bill 

Tall oat grass 

239. 

Cirsium pumilum 

Soladago Sp. 

Chrysanthemum lencanthemum 

Rudbechia hirta 

Plantago lancealata 

Plantago major 

Daucus carata 

Achillea mille folium 

Oxalis stricta 

Rumex crispus 

Arctium minus 

Lactuca scariola 

Lactucacanadensis var. latifolia 

Aster puniceus 

Potent ilIa rep tans 

Potentilla recta 

Hieracium pratense 

Linaria vulgaris 

Veronica officinalis 

Erodium ercutarium 

Ranunculus acris 

Erigeron strigosus 

Erigeron canadenis 

Equisetum arvense 

Pastinaca sativa 

Brassica rap a and kaber 

Phleum pra tense 

Agropyron repens 

Juncus tenuis 

Dactylis glomerata 

Muhlenbergia schreberi 

Anena sativa 

Carex lupulina 

Digitaria sanguinalis 

Andropogon virginicus 

Barbarea vulgaris 

Verbascum thapus 

Thalictrum revolutum 

Oenothera biennis 

Fragaria virginiana 

Geranium carolinianum 

Arrhenatherum elatius 

(L) Mert. Koch. 

Scattered species: 

Canada wild rye Elymus canadensis

240. 

RESULTSOF FOLIARANDGRANULAR 

HERBICI1'\EAPPLICATI0NSTOMIXEDBRUSHIN 1957 

gj 

w.E. Chappell and R. E. Sayre 

Virginia Agricultural Experiment Station 

Blacksburg, Virginia 

y 

In 1957 a number of chemicals and mixtures ~f chemicals were applied 

to brush growing in power line righto,f ways. The species of plants 

involved covered a wide range but the major ones were: chestnut oak, 

white oak, red oak, sassafras, black locust, red maple, hickory, sumac, 

yellow poplar and sourwood. The population of these species varied 

c("\nsiderabJ.y from one individual plot to another. This varibllity resulted 

in most of the lack of significance between treatments in the experiments 

reported here-in. Examples of the variability ~f the species and species 

location to selected treatments are presented in Table 1. 

Table 1 - Effect of treatments on various species. 

Examples of individual stems per plot. 

Species 

Red Oak 

Chestnut Oak 

Sassafras 

Black Locust 

Sumac 

Maple 

Hickory 

Black Gum 

Red Oak 

Chestnut Oak 

Sassafras 

Black Locust 

S=c 

M.lple 

H~ckory 

Black Gum 

ATA-8 

Before After 

IBK-6-100 

~~ 

18 4 107 55 

31 6 49 29 

28 144 36 59 

86 10 220 269 

96 14 

113 5b 

3' 

--1 68 21 

3 49 

245T~~~.:12Q 

~ ..£..>ter 

535 91 

99 19 

95 12 

T2 2" 

40 0 

IBK-6.10-90 

~~ 

131 

119 

51 

53 

39 

52 

66 

85 

261 

. 63 

9 

29 

4 

35 

16 

1 

y These studies were supported in part by gra~ts from the Appalachian 

Power COlll!;e.ny,AmeriCo.:lCYanE',m:Ld Compaoy1 A"'lehcraProducts 1 Inc., The 

Bartlatt n'ee Research Labol'atwriee: and ~he duPont COlllpany.

241. 

The fo).iage treatments were applied with a :lean Pl.UllPthat delivered 

7~ gallons"perminute at 300 pounds pressure PSI. The nozzle used was 

a spraying system gunjet with a No. 5 disc. A 50 gallon spray tank with 

mechanical agitation was used. In spraying an attempt was made to cover 

the entire plant but stems and basal portions of the plants were primary 

targets. 

The spray mixtures were placed into the taDk and allowed to mix 

tJrQIzIoughlybefore spraying any plants. Individual plots were sprayed with 

the entire 50 gallons at a rate of 200 to 450 gallons per acre, depending 

upon the plant size. Dividing lines between treatments were clearly marked 

with yellow paint and tagged with aluminum plant labels. 

The monuron was applied as 251Jclay pellets or 401Jgranular on No.2 

vermiculite. Application was made by hand to individual clumps of brush 

or to individual stems. 

Initial stem counts of the variClUll species were made and recorded 

shortly after the plots were sprayed. At the end of the 1958 growing 

season all green stems a.Ddroot sprouts over 6" in height w.ere counted and 

recorded. by species for each plot. Calculatinns were then made for the percentage 

top kill and sprouts as compared to the original stem counts. 

The chemicals used and the results obtained are recorded separately 

in the text. 

Results 


Experiment I - Amino Trizole - (ATA) - Time of Application 

Duplicatg plots using 8 and 12 pounds (active) of ATAwere treated in 

May, June and' July of 1957. The May tre~tments had little or no effect on 

the brush and were not counted. The results are presented in Table 2. 

Treatment 

fJ 11'". -100 gaJ..~ 

.~ 

'jOPf!II.l/ A 10* 

12 lb. -lOC gal. 500gal/ A 10 

*Estimated 

Table 2 - Time of Application of ~ 

%Top Kill 

~~ 

72.11 93.95 

99.68 96.05 

~ Resprouts 

M!!:l June ~ 

100 62.13 30.06 

100 20.76 33.67 

- -- -- -- -- -- -_. -- -- --- --- - --- --- 

In that area chosen for this test the brush was 10 - 12 ft. high and 

was predominately black locust, sumac, sassafras, and oaks. The volume 

used was very high but not uncollllDOnon brush of this size. A breakdown 

of the u:ajor species in the plots is as follows:

Some off the r1.ll:ht-of-wav in.1urv was noted in all 'Clots. Some oak and 

242. 

stems Per Acre - Before and After Treatment 

Oaks 

Sassafras 

Black Gum 

Black Locust 

Sumac 

8# ATA- June 

~-~ 

49 

28 

3 

86 

'96 

15 

144 

49 

10 

14 

l?# A'!'.A- June 

~-~ 

93 2 

198 127 

o 0 

254 3 

75 0 

- -- -- -- -'-'- -- -- -- --- -- -- -- --- 

As can be seen from the data black gum and sassafras were the two 

most resistant species in this experiment. Suma.cand black locust were 

very susceptible. 

Experiment II - Manuron Studies 

In an effort to determine the effectiveness of monuron on brush in a 

dry formulation when applied to mixed brush at different times of the 

year an experiment in which four application dates and. two rates of chemical 

was designed. The treatments were applied in June, August , October and 

December. In'the June treatments one rate of 5 grams active manuron per 

clump (1-10 stems) of brush was applied. In the August treatments a slurry 

consisting of 1 part 80~ monuron and 1 part water was used in rates of ? 

and 7~ grams per clump. In the October and December treatments 5 and 7~ 

grams per clump were applied in the granular form. Three replications were 

made. Plots were 50 x 100 ft. in size. The results are presented in Table 3. 

Table 3 - Monuron Applied At Different Dates 

Treatment ~ ! Reduction of Stems 

1. Pellets 5 gr/clump 6/4/57 79.80 

2. Slurry 5 gr slurry/clump 8/5/57 79.25 

3. Slurry 7.5 gr/clump 8/5/57 74.86 

4. Pellets 5 gr/Cl~ 10/1/57 74.06 

5. Pellets 7.5 gr/cl loll/57 74.65 

6. Pellets 5 gr/cl 1'2/19/57 72.51 

7. Pellets 7.5 gr/clump 12/19/57 73.63 

Little or no root sprouting occured in any of the treatments and the 

data includes both stem counts and root sprouts. Although the percentage 

top kill does not appear to be very high most of the stems were apparently 

dying, but many were still green at the time the counts were made. 

Notes taken early in the growing season of 1958 showed little effect 

from the October and December treatments on most plants , but as the season 

progressed all plants became chloratic , browned out and ,were defoliated in 

September When the counts were made.

243. 

Experiment III - "Standard" Mixtures 

In this experiment several more or less commonly used chemicals were 

applied to brush considered to be about optimum size for the most efficient 

sprayi~. In the area used the brush ranged from three to five feet in 

height, included a wide variety of species and was of average density. 

Six foliar treatments and one granuJ.ar application were made. Each treat:- ' 

ment was replicated at least three times and in some cases sdx replications 

were m.de. All treatments in.the llBin test area were applied in August. In 

addit1Qn to this arfla some treatments were applied in other areas to check 

on their performance but they cannot be c01ll.Pareddirectly. The results are 

presented in Table 4. 

Table 4 - "Standard 

Treatments" 

Treatment 

~Lb. in 100 gal. solution) 

Butoxyethanol esters 24-D-245T 

4 lb. 

Butoxyethanol esters 24';'D-245T 

4-10-011 

Butoxyethano1 esters 24-D-245T ~ 

II II 6-10-011 

Amino triazo1e 8 

Amino triazole 12 

Ammate 40-4(oil) 

Check (Hand cut) 

Main Test Area Other Areas 

nop Kill '!Resprouts nop Kill ~. 

75.54 

::J: 

94.00 

88.66 

77.76 

95.28 

0.00 

33.97 

32.33 

15.lj:6 

23.79 

30.51 

15.93 

85.38, 

195.19 

~~.12 

5..·92 

61.38 

11.66 

40.48 

--------------~------ 

Somewhat better results were obtained with all chemicals in the area of 

the main test than in other J,oc~t1ons. - .This was probably due to smaller brush 

in that area. In general the top kill was satisfactori but th~_p~rce'n~e . 

of resprouts left something to be deSired. 

The use of l~ oil in the mixtures increased top kill' in this experiment 

by 15i in the 4 lb. and by 110in the 6 lb. rate of the D80Testers. Ammate 

resulted in good top kill but the percentage resprouts was very high • 

.- 

Stem counts will again be made at the end of the 1959 growing season 

and a final evaluation made at that time. 

Experiment IV - Screening Test 

Several rates of ohemical and various mixtures were applied in July and 

August of 1951. Fifty gallons of total spray was used except that with 

monuron 5 grams active was applied as 25i pellets. Each treatment was 

replicated two or more times. The results of these treatments are presented 

in Table 5.

244. 



Aminotrizole I Dalapon 

Aminotrizole - Veon 100 

Aminotrizole - Veon 100 

Aminotrizole - D&T 

ACP414 (Invert emulsion) 

ACPM23A

245. 

THEEMUL3IFIC.'\.TIONOF HERBICIDES 

by 

J. W. Van Va..liI:enburg 

J. A. Kelly 

Since the introduction of the plant-growth-regulator-type 

herbicides such as 2,4-D and 2,4,5-T a decade or more ago, contractors 

have applied millions of gallons of diluted spray to unwanted vegetation. 

In so doing, much has been learned regarding the necessary and desireable 

properties for a good herbicide formulation. Thus, any activity in 

which so many have participated and contributed knOWledge rapidly assumes 

a forbidding technical appearance to the uninitiated. Also, because 

of the great importance of this work, much highly developed 

technical research has necessarily been done by countless workers. 

Accordingly, the purpose of this paper is to critically review 

the fundamental aspects of herbicide emulsifiable concentrates in order 

to develop a clear understanding of the progress made in recent years. 

To best accomplish this goal, we propose to discuss, point by 

point, the parameters directly concerned with the making of a qUality 

herbicide formulation. These include: 

1. What I s in the can? 

2. What is an emulsion? 

,. How is an emulsion made? 

4. What degree of emulsification is needed for proper brush 

control? 

5. Howmuch agitation is.required for the emulsification of 

herbicide plus oil? 

6. Can spray drift be minimized through use of a particular 

formulation? 

7. Can the activity of herbicide be enhanced significantly 

by the formulation? 

1. WHATI S IN THE CAN? 

Obviously, the primary constituent is the herbicide itself in 

a form that is assimilatable by the plant. The herbicide must be

The solubility of an emulsifier in oil ts quite important to 

good emulsification. In an article by Gladstone(2) he states that if an 

emulsifier is not soluble in oil, the solution will tend to be hazy. Upon 

standing, this haze will &a'aduallv settle out to " vi,,,,,.,,,,,lAW'''' vit.h +.h .. 

246. 

present in the amount and kind guaranteed by the label statement. This 

requires careful control of the manufacture from start to finish to insure 

that this will be so. Quality control of the formulation accomplishes this. 

In general, 2,4-D and 2,4,5-T are sold as esters, and in brush control work, 

low-volatile esters such as the glycol ether esters are extremely effective 

and find wide use. 

A second important ingredient in the formulation is the solvent. 

The purpose of the solvent is to act as a carrier for the herbicide and 

the emulsifier so that proper emulsification or solution is obtained when 

diluted. with water or oil at the time of use. The solvent has a man-sized 

job to do when one considers that this job must be properly done at the 

time the package is opened regardless of the previous history of that 

particular package. For example, a good brush killer must stand extremes 

of temperature in storage of zero degree Fahrenheit or below without 

crystallizing and yet be unaffected by summer storage at 125°F. or above 

and this repeated for several seasons~ A solvent capable of doing this is 

not chosen by whim but only after careful research and evaluation. The 

physical characteristics of typical 2,4-D and 2,4,5-T ester solvents are 

shown in Table 1. 

Table 1. 

PHYSICALCHARACTERISTICSOF TYPICAL 

2,4-D AND2,4,5-T ESTERSOLVENTS 

Mixed aniline point, degree F. -- 

Kauri-butanol value ------------- 

Aromatics, %-------------------- 

Sp. Gr. at 68°F. ----------------- 

Flashpoint, OF. (C.C.) -- _ 

Boiling range, OF. -- _ 

52-82 

79-98 

80-100 

0.860-0.895 

81-164 

274-3 86/290-495 

The emulsifier is the third important ingredient in the formulation 

and is put there for the express purpose of dispersing the herbicidecarrying 

oil in the dilution water so that homogenous emulsions can be 

formed that adequately distribute the herbicide over the area to be 

sprayed. In addition to this service, the emulsifier present in the 

formulation is called upon to emulsify as much as ten gallons of added 

fuel oil per gallon of herbicide in those situations where oil is a preferred 

additive. This is not all that is expected of the emulsifier; for 

when oil is used as the sole diluent, the emulsifier must not precipitate 

out of solution in the aliphatic diluting oil to gum up equipment and 

spray nozzles.

The hardest system to emulsify is a ga.llon of herbicide extended 

with ten gallons of fuel oil and mixed with roughly eighty-nine gallons 

of water. So, let us use this as an example of "how to make an emulsion." 

The order of mixing ingredients in such an emulsion is very important. 

The oil and emulsifiable concentrate should be premixed before the combina 

~1nn 1~ Ann~rt +n y~+~~_ 

247. 

net result that the emulsification of the oil is impaired. This is explained 

by the fact that an emulsifier works best when it has both water and oil 

solubility. 

Such emulsifiers represent much research and development effort 

on the part of formulators and the specific materia.ls used are reluctantly 

discussed, if at a.ll. Suffice it to say, that emulsifiers commonly used 

today consist of various blends of non-ionic surfactants with anionic 

surfactants. However, those possessing all of the attributes listed here 

are not readily available. 

2. WHATIS AN EMULSION? 

An herbicida.l emulsifiable concentrate is essentially an oil mixed 

with an emulsifying agent. When we pour this oil, or emulsifiable concentrate, 

into water we have to fight the old adage that oil and water just 

don I t mix. When we mix the oil and water, we want that oil to break up 

into fine droplets and to be dispersed in the water. When finely divided 

oil droplets are dispersed (being a discontinuous phase) in the water (a 

continuous phase), we have what is called an oil in water emulsion. 

Figure 1 shows a microscopic picture of a brush killer extended with oil 

and then emulsified in water. Magnification is several hundred fold and 

you can see that the oil has a random particle size, that is, some droplets 

are very fine while others are larger. 

As the oil droplets become finer, the emulsion assumes a creamier 

appearance and becomes what we call a tight emulsion. If these oil droplets 

become too large, they will rise to the surface of a water mixture 

and form an oily layer (this is of course assuming the oil is lighter 

than water). If all the droplets are fine enough, the droplets may remain 

in an emulsified form but they may not stay in the same place. In other 

words, the emulsion may have a tendency to cream. When an emulsion creams, 

one can see two phases: A layer containing a high concentration of 

emulsified oil and a region containing a much lower concentration of 

emulsified oil. We will have more to say about this later. 

One comment is appropriate here as to why emulsions are made. 

Undiluted, an herbicide would have to be applied at approximately one drop 

of liqUid per square foot. By emulsifying and diluting the herbicide, it 

is possible to spread more finer droplets uniformly over the same area. 

3. HOWIS AN EMULSIONMADE?

It would be ideal if one could mix oil, concentrate and water in 

any order, so, an actual experiment was devised to test the importance of 

order of addition. 

A Hardie Sprayer mounted on a power wagon was secured for this 

experiment. The sprayer had a one hundred gallon tank which was agitated 

vigorously with paddle and bypass agitation. One gallon of brush killer 

was added to eighty-nine gallons of water and then ten gallons of oil were 

added. The order of addition, then, was: Water, brush killer and then 

oil, each added separately. The solution received maximumagitation for 

several minutes after which samples of liquid were taken from the top, 

middle and bottom of the spray tank. Figure 2 shows the oiling out rate 

of two prominent brush killer formulations. As you can see, oiling out 

is greatly increased when the oil is not premixed with the emulsifiable 

concentrate. This oil that rises to the surface has not had a chance to 

dissolve any emUlsifier, and consequently, just doesn't emUlsify. The 

bottom two lines show how much less oiling out occurs when oil and 

herbicide are premixed. 

Therefore, for any herbicide-oil program, it is recommended 

that the user mix oil and herbicide first then add this mixture to water. 

An excellent emulsion can be obtained in the following manner: 

Start adding water to the spray tank. Immediately, add premixed 

oil and herbicide. Continue adding the rest of the water. In cases where 

bypass agitation alone is used, this procedure will yield excellent 

emulsions. 

Figure 2. 

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249. 

4. NOW, WEHAVEAN EMULSIONMADE, BUT HOWGOODAN EMULSIONIS REQUIRED 

FOR GOODBRUSHCONTROL? 

For maximumbrush control, we want the largest possible spray ) 

deposit on foliage for a given volume of spray. Ben-Amotz and Hoskins(l , 

way back in 1937, found that maximum oil deposit is obtained with merely 

a mechanical mixture of oil and water. As more and more wetting agent 

was added, deposit actually decreased. 

These results have been explained by Gladstone (3) • A tight 

emulsion consists of oil surrounded by water. When water hits the waxy 

outer layers of a plant, water will tend to ball up and run off and the 

herbicide is lost. Also, laboratory tests show that if there is a lot of 

wetting agent present spray deposit is minimized in that run off is 

reached with less spray. So, a tight emulsion results in less herbicidal 

spray deposit on a plant. 

Conversely, in a relatively loose emulsion, when spray hits 

foliage, the oily portion of the spray drops out of the mixture and wets 

foliage with more of the active ingredient. The water can run off leaving 

an oily layer behind resulting in better brush control. 

Accordingly, many herbicide formulations are designed to give 

only adequate emulsification of the oil solution in water. The emulsions 

are relatively fast-breaking so that when a spray hits foliage, maximum 

deposit may be obtained and consequently better brush control may result. 

The addition of wetting agents in the field may reduce spray deposit 

though the leaf appears to be wetted better. 

5. HOWMUCHAGITATION IS REQUIREDFOR THE EMULSIFICATIONOF HERBICIDES 

PLUS OIL? 

Dased on what has been related so far, it can be seen that emulsification 

of oil plus herbicide is a hard job. Therefore, one needs 

agitation to break up and disperse the oily phase into the aqueous phase. 

Excellent emulsions can be obtained with either paddle or bypass agitation. 

Greater precautions must be observed, however, in making up emulsions 

using bypass agitation alone. The ratio of volume of solution through 

the bypass to spray tank volume should be high to achieve good dispersions. 

In other words, a high capacity pump is essential. Sufficient time should 

be allowed for the complete solution to pass through the bypass system 

several times-~the chemical engineers tell us that six times are required. 

-- 

The contractor who uses bypass agitation alone is confronted by 

a problem that the contractor who uses paddle agitation does not have. 

This problem is the homogeneity of the spray solution at the time of 

spraying. When the contractor sprays from a rig with bypass agitation 

alone, the volume of solution returning to the spray tank drops to a

250. 

minimum. The spray solution is vittUtl.11y without agitation. Now 0.11 

emulsions on standing without agitation will separate into two phases--a 

concentrated and a dilute phase. The rate of separation will depend upon 

the manner of mixing ingredients, the hardness of the water, water 

temperature, and the extent of the agitation. This rate of separation 

will vary a great deal with every spray rig and may cause variations in 

the concentration of herbicide of from ten to fifty per cent in the first 

ten minutes after agitation has stopped. Large concentration variations 

could have serious consequences in producing erratic results. Therefore, 

the contractor should insure himself that his method of operation results 

in homogeneous solutions. The contractor can do this very easily by 

taking samples of spray solutions from various sections of the spray 

tank at various time intervals. He should then observe the amount of 

phase separation in each sample to see how much variation he actually is 

obtaining in his mixing procedure. 

It should be recommended that paddle agitation will assure 

homogeneous spray solutions. The contractor should be very careful in 

using bypass agitation alone. 

6. CANSPRAYDRIFl' BE MINIMIZEDTHROUGHUSE OF A PARTICUIARFORMUIATION? 

A problem that frequently arises in the use of herbicidal spray 

solutions is drift. Along highways and railroad riglt of ways, there are 

many areas that border highly susceptible crops and one just does not 

dare spray normal herbicidal spray solutions for fear the Wind will carry 

the herbicide into the susceptible crop area. A recent development of 

the chemical industry to combat drift is the use of invert emulsions. 

Invert emulsions are, as the word indicates, the reverse of 

normal emulsions. They contain minute droplets of water dispersed in oil 

and are, therefore, called water in oil emulsions. 

A special f01"lllulation is required for invert formation. A special 

emulsifier has to be used which favors the formation of an invert. Then, 

too, the order of addition of chemicals is different for invert formation. 

Here one adds the oil and herbicidal concentrate to a spray tank first. 

Then the water is added to the oil with good agitation. As more and more 

water is added and the percentage of water in the spray mixture gets 

higher and higher, the spray solution becomes thicker and thicker. It is 

possible to add a sufficient amount of water such that a spray solution 

obtains almost a mayonnaise type consistency. This is obtained when 

approximately 85%water has been added. This thick emulsion can be sprayed 

using appropriate nozzles and the high viscosity results in large spray 

droplets Which are relatively unaffected by wind. Merely adding oil to 

conventional oil-water emulsions does not reduce drift. 

Invert emulsions have several plus factors. These are (1) that 

much larger herbicide deposits can be built up on foliage and (2) that

good deposits can be obtained in spite of wet foliage. It is interesting 

that these invert emulsions can actually be sprayed in the rain and good 

brush control will result. 

251. 

Figure 3 shows the type of deposit one can get with invert 

emulsions. 

7. CANTHE ACTIVITYOF AN HERBICIDEBE ENHANCEDSIGNIFICANTLYBY THE 

FORMULATION? 

As is well known, the addition of oil to an herbicide has a 

significant effect on the activity of the herbicide. An oil program 

results in a faster more uniform brown-out and better control of pine. 

However, here are several disadvantages to an oil program. 

In many out of the way places, it is inconvenient to carry in 

the extra oil, added oil is harder to emulsify, and a larger percentage 

of resprouting of brush is likely to occur. Also, oil and the labor of 

handling it is expensive. It would be ideal if an emulsifiable concentrate 

could be designed which would be as effective as an herbicide plus 

oil but without having to add any oil. 

"Forron"a promises to 'fulfill these requirements. It has been 

under test for the last several years and many of you have had a chance 

to evaluate it. Brown-out is obtained with "Forron" just as fast as with 

brush killer plus oil. Brush control is in many cases better than an 

oil program. No oil needs to be hauled into out of the way places because 

"Forron" is designed for use without added oil. Homogeneous spray solutions 

are easily obtained from "Forron" thus reducing the concern a spray 

operator needs to give to his sprayer agitation requirements. 

"Forron" contains an "extender" specially developed by The Dow 

Chemical Companyl This extender.causes the herbicide to penetrate 

foliage and translocate into the stem better than an herbicide plus oil. 

Brush control results look exceedingly good with "Forron". 

Today, we have tried to review some of the fundamentals of the 

emulsification of herbicides. We have reviewed the components of a formulation 

and how a formulation is made to emulsify. We have reviewed some 

of the problems that one encounters in emulsifying added oil to herbicides. 

We have reviewed how spray drift can Virtually be eliminated through the 

use of invert emulsions. We have mentioned how a specially designed 

emulsifiable concentrate will haVe the effect of oil without the use of 

oil. There is more and more research being done by many companies to 

make herbicidal emulsions handle and perform more effectively. This is 

not the end, this is a continued story. 

A:.rrademark of The DowChemical Company 

BIBLIOGRAPHY 

(1) Y.Ben Amotz and W. M. Hoskins, J. Econ. EntomologY,lQ,879(1947~. 

(?) Arthur M. Gladstone, AGRICULTURAL CHEMICALS,~No.l?38 (1957)

Survey 

of Brush on Pole Line Rights-of-Way 

,C. J. Waldron Y 

The people responsible !orpole line right-ot-way' maintenance are usually required 

to set up year-to-year schedules so that funds can be bUdgeted for 

this purpose. In order to estimate coS'ts and decide· on methods to use it is 

necessary to have'det'dls on condition of the unwanted vegetation. 

In its contract forms for electric' and telephone line construction the Rural 

Electrification Administration defines right-of-way clearing units as one 

thousand feet in length, .having widths in multiples of ten up to one hundred 

feet. Width depends on. type of line to be constructed. The length to be 

cleared is measured in a straight .line parallel to the 11n.e between poles 

and across the maximumdimension of follage cleared (not trunk) projected to 

the ground line. All trees and underbrush across the width of the right-ofway' 

are considered to be grouped together as a single length in measuring the 

total length of clearing. Spaces along the right:"of-way in which no trees 

are to be removed or trimmed or' underbrush cleared are omitted from the total 

measurement. All lengths thus amved at, added together and divided by one 

thousand, give the number of thousand-foot units of clearing. . 

This clearing unit deals only with length of right-of-way of specified widths 

for estimating and bidding clearing costs. In itself it requires no data on 

species, height or density of growth to be cleared. No comparisons of unit 

ccsts reflecting the effect at these variables can be made until supplementary 

data are obtained. . 

Experience with REAborrowers hAs shown. the advisabilit.y of including in the 

survey of brush on pole lin.erights-of-waythe tollowing data: 

1. Location and number of clearing units of specified width. 

2. Terrain (grades, natural obstruet:lo 1'1,8, and accessibility). 

3. Growth conditions (average height and density). 

4. Species present and relative count of thnse predominating. 

5. Available water for foliage spraying. 

6. Location of crops grown near rights-of-way that may 

limit method and time of spraying. 

Items $ and 6 are applicable tor consideration of chemical treatment. Item 4 

is much more necessary tor consideration of chemical treatment than tor other 

methods. 

Time spent in the office to plan field work required for the survey will result 

in greater accuracy of data obtained, as well as the expenditure of a 

minimum amount of time on the fieldwork. Data that are useful for planning 

the field work include records of clearing for construction and of reclear1ng 

work. System maps should be available, showing location and number of units 

originally cleared as well as those recleared, and dates when such work was 

done. Inowledge of rate of growth in representative portions of the ay'stem . 

gElectrical Engineer, Rural Electrification Adm:lnistration~ lIIa.Ahing·~.on. D~C.

253. 

will be of value in determining frequency of reclearing, widening or other 

maintenance work. Supervisory personnel who drive along most of the important 

lines at least once a year can take data that will prove invaluable in 

keeping records and maps up to date. Mileage of line requiring maintenance 

and total line miles traveled can be recorded trom the vehicle odometer. 

other significant data easily seen can be recorded and later transferred to 

records and maps in the office. It there are no records of original clearing 

or of maintenance work previously done, it will be necessary to take 

observations on a purely sampling basis on live to ten percent of the total 

system mileage. 

In conducting the survey, observations should be made at enough locations to 

assure that all important conditions have been represented. If conditions 

are fairly unifom, a relativeJy few observations will be required. Grouping 

atICording to species and age (or time since last right-of-way maintenance 

was done) will enable the person making the survey to detennine where 

and hCMmany observations he should take. 

Species is of great significance when chemical treatment is to be done and 

should be recorded by name and relative COllnt of those predominating on the 

section being sarr.pled. Density and height are also recorded on a sampling 

basis and can most conveniently .be indicated by symbols. 

Density (crewn cover) should be considered as a maximumhorizontal dimension 

of the foliage cleared, projected to ground level. It is expressed as 

percent of ground area overhung by foliage of the woody growth: 

Heavy - over 70 percent coVer 

Medium - 40 to 70 percent cover 

Light - 10 to 39 pere ent cover 

The SUl"\l'ey should also include grouping according to average height of the 

major portion of the growth: 

Tall - over 15feet 

Intermediate - 10 to 15 feet 

Short - 4 to 9 feet 

If desired, a different provision could be made for "tall" growth, classifying 

by diameter all trees over four inches in diameter near the ground~ 

This prceedure would largeJy el1m1nate the "tall" classification for brush 

and would involve a count of individual trees. Grewth less than four feet 

tall would not require immediate clearing and could be recorded as ''very 

short" for future reference. 

By classifying all the brush according to density and height a maximumof 

nine groups would be recorded: 

HT-heavy tall Ml'--medium tall 

HI-heavy intemediate MI--medium intemediate 

HS-heavy short M3-medium short 

LT-l1ght tall 

LI-light intermedia te 

LS-l1ght short 

Sufficient records should be kept of right-of-way maintenance work done so 

'-- that past work can be analyzed in planning future work. These records, together 

with data acquired from the brush survey, are essential to the planning 

and execution of an economical and effective 10tlll-raJUZe r:!.l!'ht.-of'-WAV .

254. 

The Theory and Practice 

'lillil.llll C. 

of Successful Selective Control of "brush" 

by Chemicals. 

1 ' 2 

Hall and ~illiam h.. Niering 

In "brush" control work weed killers are being used jJrimarily as broadc~st 

or selective sprays. The former involves the application of the chemical 

to all the brush comprising a mixture of trees and shrubs, and incidentally 

all herbaceous vegetation as well, whereas the selective technique emphasizes 

tre~ting only those il1ants which are undesirable in fllly given situation and 

preservin5 all others. Over the years the broadcast technique has been most 

widely employed because it is initially inexpensive, simple to apf>ly and 

requires little or no knowledge of the ~lants being treated. liowever, in 

recent years, at this conference and elsewhere, there has been increased concern 

among wildlife agencies, conservation groups, some progressive utilities, 

and private citizens that greater benefits are derived from the selective 

approach whereby all the facets of the problem are intelligently evaluated. 

':Thatis the theory behind the selective approach? In commercial application 

it usually involves the removal of potentially tall growth, usually 

trees with a minimumof injury to the low plants including shrubs, broudleafed 

flowering plants and certain grasses. The presence of this low growth, 

especially the shrubs, '~hich remains tends to keep out invading forest trees, 

thereby maintaining the line with a stable low-growth type over the years. 

This desirable plant cover will directly reflect low maintenance costs on a 

long-range basis. In addition, conservation benefits specifically result in 

better wildlife und game habitat as well as in the preservation of the native 

flowering plants. This ultimately results in an aesthetically desirable picture 

and therefore good public relations to the company. 

Can selective spraying be done by regular spray crews? 

no problem if this is the aim of the client and contractor. 

10wJ.ngpoints should be taken into account: 

Yes. There is 

However, the fo1- 

1. "Tarkcrews must understand the objectives to be achieved. 

2. The foreman need not necessarily be technically trained. 

However, both he and the crew must be taught to recognize 

those plants which are to be saved. 

3. tit the start of 'each job, the foreman and crew must be 

closely supervised. 

4. The quality of the job will be directly dependent upon how 

seriously the men have taken the assignment and how well 

the,foreman has done his job. 

1 nrborea1 Associates, Harriman, NewYork 

2 Associate Professor of Botany, Connecticut College. NewLondon, Conn.

255. 

·~ith regt I'd to application several techniques have been successfully used 

in commercial practice; their effectiveness related to the degree of selectivity 

desired. Amongthe most effective is the oil basal technique. However, 

stem-foliage sprays have also been adopted by the senior author to this 

approach using Ammate, 2,4,5-T, 2,4-D and 2,4,5-T in combination and amino 

triozole. Soil treatments with urea compounds show considerable promise for 

selective work. 

As would be expected in comparing the techniques, greater root-kill is 

attained with the oil basal and least disturbance occurs to the low ground 

cover. However, with good specifications and careful supervision much of the 

ground cover can be spared and good control of many woody species can be 

ascertained with stem-foliage sprays. 

What species have been treated, with what effectiveness, cnd what plant 

cover has been preserved? In the northeast, the basal treatment using oil 

and 2,4,5-T has been effective on practically all tree species treated at any 

time of the year, except root-suckering species which are most easily eliminated 

by late summer ap,lications. \Vith the stem-foliage sprays good control 

of red and chestnut oak, sugar and red maple, ash, elm, hickory, black locust, 

linden, birch and wild cherry has been observed by the senior author. AS a 

result of selective spraying, areas dominated by trees and shrubs have been 

converted to laurel, huckleberry, blueberry, viburnum, azalea, dogwood, hazel 

and sweet fern along with the existing broad-leafed flowering plants and 

grasses. 

Howdoes this approach compare with less selective treatments'! Initially 

the cost may be hi&her. However, since better control of the unwanted plants 

is attained initiaLly and fewer ~reatments are needed costs tend to compare 

favorably when prorated over the years. After more than five years of experience 

~ith selective spraying the senior Buthor has found the selective 

approach competitive with less selective techniques when all benefits are 

evaluated. 

In practice, this appr-oach is applicable to brush control along roadsides 

'Nhere "brush" interferes with visibility. Here, in general, only trees are 

removed, except on the inner sides of curves where both trees and shrubs might 

have to be sprayed for good sight line conditions. By following this approach 

unsightly brown cuts are minimizeQ. and the existing native shrubs and ",11d 

flowers which are spared serve to enhance the beauty of our roadsides. When 

this approach is applied on power lines, the trees and other tall undesirable 

growth directly under the wires are selectively removed. Low shrubby growth 

is preserved. On the edges be,yond the outer lines only the potentially tall 

~rowing trees are sprayed since taller growth can be tolerated here. Regardless 

of the situation the basic idea is to fit the spray technique to the 

particular "brush" control problem at hand and accomplish it as selectively as 

possible. 

In conclusion it may be stated that this approach is no longer a theory. 

It has had an adequate test in practice by several commercial companies. The 

present condition of the lines after more than five years of observations 

throughout the northeast is adequate proof that this appr-oach not only accom-

256. 

~lishes the objectives of the client but benefits the ~ild life, thE hunter 

and naturalist in addition to providing good ;,ublic relations to the company 

The question may yet be asked, how well will the shrubs tend to keep out trees 

and take over future maintenance? Although many situations could be cited, 

two areas are of especial interest. After five years on the right-of:..way demonstration 

area at Penn. State the investigators state that the tight low' 

shrub cover resulting from the selective basal treatment has held beck the 

development of seedlings, sprouts, and suckers for at least five yeers. On a 

line at Ten ,;Iile River, NewYork over fifteen years has passed and shrubs are 

still doing the job. The selective approach has been proven. It merely 

awaits ap,.lica tion by those who are sufficiently progressive to emplo;}'it. 

Again, however, it should be mentioned that to get selective work one must 

want it and work for it; one must provide good supervision and get his crew 

foreman saving the right plants at the start of the job. One must check his 

work if the selectivity is to be achieved for maximumcompany and ~blic 

benefit.

'- 

PLANSFOR RAGV/EELCONTROLPROGRAMIN N.":WYORKSTl\TE* 

By 

Alexander Rihm, Jr. 

Executive Secretary 

Air P~ilution Control Board 

257. 

Air is a vital, natural resource without which we can live only a few 

minutes. It also is a commodity which is easily polluted. For exsmple, while 

you are sitting in this room listening to me talk, while you are merely performing 

the normal, involuntary function of inhaling and exhaling, you are 

polluting the atmosphere with carbon dioxide, bacteria, viruses and a number 

of other things. 

Several of you are smoking. You also are polluting the air, the natural 

resource we all must, utilize to stay alive. 

These things are pretty obvious to you all, 1 1m certain. I point them 

out merely to demonstrate that in our ordina.ry, everyday experience there 

really isn't any completely pure air. Go into the wilderness far removed from 

our fuming, industrialized civilization. Even there the atmosphere is polluted 

by nature - with molds, pollens, insect parts, products of vegetable, mineral 

and animal decomposition, and by spores and dusts of every conceivable kind. 

For many years, man has taken limited steps to protect air, our most 

valuable naturel resource. Smoke control ordinances, for instance, have been 

in effect since the 13th century. More recently, cOIDlllUni ties have become more 

concerned with control of some newer contaminants in the atmosphere and ordinences 

are being passed prohibiting dust emissions, odoriferous compounds, and 

similar substances. We have become concerned, slso, with the so-called netural 

atmospheric contaminants which I mentioned a moment ago. These are contaminants 

which become airborne by natural means or as an indirect result of man's 

activities. Pollen is one of these natural contaminants. 

At a recent meeting in Paris* of medical scientists from 40 nations it was 

announced that allergies now rate third, after cancer and heart ailments, on 

the list of diseases in France and the United States. Furthermore it was reported 

that allergies are on the increase -- pollens in the United States are 

the principal cause ~f, allergies. 

In New York Sta:te', alone, somewhere between one and two million people 

suffer from pollinosis. Of these, gross estimates indicate that about one 

million or more suffer longer thsn six weeks each year becvuse of the presence 

* . Presented at the AnIlllBl Meeting of the Public Health Secetion of the North':' 

eastern Weed Control Conference, Hotel New Yorker, New York City, 

January 8, 1959. 

* November, 1958.

258. 

of ragweed pollen in the air. If we use nationally accepted figures, 30 per _/ 

cent of these people eventually develop chronic asthma. 

People who react to pollen are affected to various degrees, ranging from 

minor nose and eye symptoms to-complete invalidism. Once a person is sensitized 

he remaina so and will continue to exhibit symptoms each time he is exposed 

to a sufficient concentration of the sensiti~ing agent. 

Follen in the atmosphere may come from various sources. Five grasses in 

NewYork State - timothy, red-top, sweet-vernal grass, Kentucky blue-grass, 

orchard grass - cause most grass reactions. 

Trees, too, cause pollinosis: oak and birch for inatance, and certain 

fruit trees, cause serious reactions among sensitive people. For obvious reasons, 

however, there is littleth$tcan be done to control grass pollens and 

tree pollena because these are important economic crops. 

Control of ragweed pollen presents an entirely different situation. Here 

we have a plant which is of only minor economic importance. It is a plant which 

quickly takes over abused, neglected land from which it extracts nutrienta and 

grows prolifically on seemingly barren soil. It does have one minor oconomic 

value, though; it stabilizes the .soil snd prevents erosion until more permanent 

grasses can be established. 

Because it does take over quickly on abused or" neglected land, it thrives 

along highways, in vacant lots, and on abandoned, poorly cultivated farmlands. 

Short ragweed flouriahes in relatively dry areas while giant ragweed is more 

commonly found in wetter areas. By far, the largest part of the hay fever 

problem in NewYork State can be attributed to short ragweed. 

If we could increase the fertility of all abused and neglected land in 

the United States, establish good grass cover on it and control ragweed in 

farm crops, we probebly could reduce ragweed pollen concentrations to the 

point where few people would react. 

Let I S go back for a minute: in 1951 the NewYork State Joint Legislative 

Committee on Natural Resources began a study of atmospheric pollution. The 

committee adopted the idea that pollen because of its air-borne nature and 

because it causes serious health .problems is an atmospheric contaminant with 

which the Sta te should be concerned. 

Pollen generated in one New York State cOllllllUnityis X'98.dily tranapor~ 

by atmospheric currents to other communities. In fact, pollen can be transported 

over such long distances that it is really s federal, perhaps even an 

international, problem. With these considerations in mind, pollen was defined 

in New York Skte Air Pollution control legislation as an importsnt 

eontaminant with which the Air Pollution Control Board would be concerned. 

Even before the NewYork State Air Pollution Control Act was passed, 

laws in force and effect prOVided municipalities with power to control noxious 

weeds. Towns, villages, cities and eountd.e s all have power to control ragweed, 

and 1II8ny lI1I1Ilicipalities conducted control programs with varying success.

Generally, however, none of these campaigns was successful because a significant 

reduction in pollen concentration could not be demonstrated. To my 

knowledge, only one limited epidemiological study was conducted to determine 

whether ragweed control in a small area could be successful and this study, 

conducted in a borough of NewYork City also showed that pollen control on 

a limited area basis was relati:vely unsuccessful. 

If the cause of disease is known, steps can be taken to prevent it. 

Therefore we, in NewYork State, have organized a program which we believe 

will eventually lead to its control. 

In making our plens, we enumerated what we know about ragweed and what 

else we must know before we can conduct an intelligent control campaign. 

First of all, what do we know? 

1) We know that a number of people are what we might term "all er gyprone". 

They might react only to ragweed or they might react to a host fL. 

allergens. In fact, they may react to other allergens and not to ragweed. 

As much as ten per cent of our population is allergy-prone. 

2) We know that ragweed pollen produces allergic symptoms in a high 

percentage of allergy-prone individuals. 

3) We know that ragweed pollens are readily transported long distances 

by atmospheric currents. Ragweed pollen, for instance, has been found in 

Greenland, which has nc ragweed plants. 

4) We know that, with the exception of two limited areas, ragweed 

flourishes throughout NewYork State and produces pollen from about the middle 

of August until the plant is killed by frost; that the production of ragweed 

pollen is dependent upon the length of the day and not on the age of the plant, 

degree of fertility, and other factors. 

5) We know that ragweed flourishes on disturbed land of poor fertility, 

that it will not germinate and flourish on well-established, fertile grassland. 

6)' We know that individuals vary in their sensitivity to ragweed 

pollen. 

7) We know that most people cannot recognize the ragweed plant. 

8) We know many characteristics of the ragweed plant, such as the 

amount of pollen it produces, the time of day when most of it is produced, 

how it is produced. 

9) We know that ragweed plants can be killed by mowing close to the 

ground, and by certain chemical sprays. 

With all we know about ragweed, how it grows, and what effect it has 

on our populetion, it would seem that there is enough information available for 

us to begin a program to eliminate this source of pollinosis. Thera are, however, 

important links missing in our chain of knowledge. What are some 

259.

Secondly, a research program is being dflslgned to find answers to some of 

t.he Illissing links in our chain or; information. The Ai:r I'l'lllut.ioll Control Board 

260. 

of 

these? 

1) We know that ragweed is transported long distances but we need to 

know whether its ability to sensitize is influenced by weathering, by moisture, 

high temperatures and sunlight in the atmosphere. It is extremely important 

to know this because this factor alone governs the size of the area which 

must be effectively controllad. 

2) We need to develop impr~ed techniques for sampling pollen • 

.3) . We need to know more about ·the mechanisms of sensitization, about 

how much of a pollen 40" sensitizes an individual and mskes him susceptible 

to hayfever. We need to know what other factors, such as diet, fatigue, 

emotions, temperature., and humidity, enter into this dose-response relationahip. 

We need to know if there is a' thr&shold below which ragweed sufferers 

do not exhibit observable symptoms. We need to know if this threshold varies 

from individual to individual and if so, what percentage of the population 

might be expected to react at what concentrations. 

4) We also need to know more about the meteorological factors affecting 

the dispersion of pollen in its broader sense; how daily pollen releases may 

be related to weather; the effects of solar radiation, air temperature, humidity 

and wind speed and manner of dispersion once it is airborne. 

5) We need to know more about,' the fate of pollen in the atmosphere, 

where it goes, and what happens when it settles on soil or water. 

Knowing some facts, and what we need to know to fill in the missing.links 

in our chain of information, a long-range program was designed by the Air Pollution 

Control Board. We believe it will evantually lead to diminution of 

ragweed pollinosis in New York State. 

It is evident that sny program such as this will not succeed without 

public awareness of the problem and of control efforts which are being attempted. 

With a fully informed public, needed fi%lanc1al support, private 

and offioial assistance and cooperation' can be obtained. People must recognize 

what is causing disease, they must know what they as individuals can do, they 

must be brought in t9 assist in the program. Only in this way csn their support 

be gained. 

Information and education, therefore, is a first step in.this program. 

The New York State Air Pollution Control Board has already emberked on this 

activity. Last summer, films for television presentation were prepared to 

assist the public in recognizing.and controlling ragweed. A pollen sampling 

and counting network was set up, and during the ragweed season, with the 

cooperation of United Press International, local radio and television news 

services, ragweed counts were made available to all LccaL news services in 

the state.

261. 

assist in designing a research program, and funds already have been requested 

in neit year's budget for su~port of these activities. 

Finally, we willconGuct scientific programs, ib cooperation with local 

agencies, to Gemonstrate the types of control efforts which can be exerted on 

a corr~unity basis. Wewill do extensiv~ sampling of the atmosphere as part 

of these studies and correlate the results with epidemiological and meteor~ 

logical data in order to evaluate our efforts to reduce pollinosis. Our work 

will be gUided by our Technical Advisory Council, the membership of which is 

made up of leaders in several fields which contribute to a knowledge of 

pollinosis. 

Although we need to know a,great deal more about ragweed, there is one 

thing of which we are confident: that if all of us bring our energy to bear 

on a hay fever relief project, the least we Can accomplish is a giant step 

toward making life more livable for the heIf-Million sufferers in ourstete. 

And, who can say exactly how far this step will take us? 

#

262. 

BOTANICALRFSFAHCHONATMCEPHERICP01.LUTION 

W. H. Wagner, Jr. 

The University of Michigan Project on Atmospheric Pollution by Aeroallergens 

is directed by Dr. John M. Sheldon (Medical School) and Dr. E. 

Wendell Hewson (Coll~ge of Engineering) under Public Health Service Research 

Grant No. E-1379. This is a cooperative enterprise, utilizing the professional 

viewpoints and techniques of medical., meteorological, public health, 

and botanical researchers in order to develop a comprehensive program of 

stuqy of aeroallergen-producing plants and their pollen, of the means b,r 

which pollen is dispersed in the atmosphere, and of the nature of the 

physiological reaction of sensitive individuals. The immediate goal is to 

better our understanding of fundamental aspects of the problem. The 

botanical research of the last several year s has focussed on the ragweeds. 

As background for this work, one of the primary contributions has been llAn 

Annotated Bibliography of Ragweed (Ambrosia)" which is soon to be published. 

and which brings together the published literature on all aspects of the 

biology of ragweeds for ready use by members of the different fields. The 

botanists 'ave also oouoel:'tled t!:lell8e1v88 with providing plants for extr ... 

seasonal experiments, with ascertaining the causes of flowering in different 

areas, the origin and migration of the species of ragweeds, the destruction 

of pollen in the s oil, the production and discharge of poJJan by the flowers, 

and the biology of the pollen grain, including the growth of the pollen tube. 

It is our belief that the life of the ragweed plant needs to be understood 

in all its phases. A stuqy of the biology of ragweeds may ultimately 

aid us in devising better methods of control of either the whole plant or of 

the production of its pollen. Such problems as why some years have apparently 

heavier pollen loads than obher-sj or why for periods of several days during 

a given season, the amount of pollen in the air diminishes, are ones we 

seek to understand. Numerous other botaJllt,cal questions brought up by our 

colleagues who are working on other aspects of the aeroallergen problem 

force us to examine the plant more carefully than ever before. 

One of bur primary activities has been to prepare plants for preseasonal 

experiments, at a time when only the pollen of artificially grown 

MCWeeds would be in the air. This was necessary since during the regular 

ragweed period, the plants are scattered over the countryside and we needed 

a tecJ:mique to localize the source. A small experiment using only 136 

pollen-producine plants in June, 1956, was so encouraging that it was greatly 

expanded in 1957 and 1958, when Cf'{er3000 plants were closely ~rouped in a 

circle about 26 ft. in diameter and set out in an open field. The plants 

for these experiments were grown in greenhouses of the University of Michigan 

Botanical Gardens from seed planted around April 1st of each year. 

If care was not t!i

The perennial ragweeds, Ambrosia coronopifolia and A. pSilostac~ are 

less commonthan the others except in the west, but they-have a spe ca 

interest in the ~ever problem because of their tendency to produce pollen 

two or three weeks ahead of the a nnual species. Because of this fact, and 

.because the perennial ragweeds seaned to be invading Michigan and spreading 

their ranges eastward, we made a special study of these plants in this state. 

We discovered the perennial ragweed, A. coronopifolia, in 18 new counties, 

bringing the tot~ to 43. A careful 'Surveyof1;he historical evidence 

reveals that it was probably wholly introduced from further west where it is 

native. No collections of this species are known in Michigan prior to 1900, 

slthough many botanists explored the state in the Jast century. It forms 

large clones by proliferation from roots in distUllbed habitats such as roadsides 

and railw~sl especially around populated areas, and, unlike the annTh~ 

species, !.. artemisiifolia, it can invade grassy fieMs. The substrate is 

263. 

27 d~s under shortened light exposures less than 12 hours, in contrast to 

85 d~ for the full-d~ control. Thus it was necessary to supplement the 

shorter days of April and early May with artificial light in order to have 

plants large enough to produce ample pollen in Juno. Tho pre-seasonal 

experiments were carried out with a pollen source 'CI~.6o days before the 

regular pollen season, and the botanists were able to make a number of careful 

observations on pollen production during these experiments. The 

meteorologists and medical workers simultaneously carried out studies on the 

atmospheric dispersal of pollen and the effects of the pollen source on 

volunteer aensitive persons. 

These experiments were conducted wi th the "101f" or IIcommonragweed, II 

Ambrosia artemisiifolia var , elatior. This, and the IIgiant ragweed, II A. 

trifiaa, are probably the most important causes of ragweed h~tever·innortheastern 

and central United States, but other species and varieties also 

possess varying degrees of importanoe in the problem. We have found by 

bringing together varieties of common ragweed into the greenhouse and growing 

them under essentially uniform conditions that their behavior in terms 

of growth ,.period and pollen production differs widely. In 1958, plonts 

were obtai. ned from Nova Scotia and Louisiana to compare with the var iety 

commonin southern Michigan. The plants from Nova Scotia and Louisiana were 

picked as young seedlings and transferred to the University of Michigan 

BotaniCal Gardens; the plants from S. Michigan were observed in the field.. 

The following data resulted: 

-----------------------------------------------------------~---- - - - - - - - ---- 

NOVASCOTIA MICHmAN LOUISIANA 

Approx. time of 

germination of se. 

Began flowering 

June 1 

July 15 

May 1 

August 15 

April 1 

September 15 

---------------------------------------------------------------------------- 

This preliminary study emphasizes the genetic diversity that exists in one 

species, Ambrosia artemisiifolia over its wide range, a diversity which is 

reflected also in the structure of the plants-the pJants from the far north 

tend to be very much smaller than the Ilgiant" plants of the south.

264. 

A. coronopifolia are smaller than those. previously reported in J... silostac 

1'20 microns in. iiiameterrathor than 23), and the chromosome nUllloer s !!,,"'I'I • 

An heretofore undes cnbod perennial raL'Weed, Ambrosia X intergradiens 

was discovered that differs from.A. coronopifoUa inhiliriness, coior, leaf 

cutting, petiole length, and fruit: structure. Its characteristics are intermediate 

between the latter and tho annual A. artomisillolia znd it is interpreted 

as their natural hybrid. . The new ra&-1IeCdturned out to be unexpectedly 

common, and a large nUlllber of populAtions have been observed in 15 counties 

of Michigan. It will probably be found elsewhere where the two parental 

ragweeds grow together. It inherits the perennial reproductive ability of 

A. coronopifolia am is therefore able to form large populatLons, but these 

are mainly or wholly sterile, onlyl.6 per cent of thef1owersfo:mling nomal .. 

appearing fruits, and only 45 per cent of the pollon grains containing living 

matter. Pollen size of this eOlllplex of ragweeds correlates with chromosome 

numbez-s A. artemisillolia with 2n ",)6 has the Smallest; !. coronopifolia lii th 

2n .. 72 Is next; anaA. PSilostam with 2n "'ca. 108 is largest •. The new 

hYbrid permnial ragweed(iocs no~t into the sequence, but its grains are 

so var1c"t1>leam its division processes so irrQgularthat this probably affects 

the size of the pollen. It is our \:l~efthat a full understanding of the 

evolution ann. migration of raeweedsldll have to incl.ude studies in warmer 

regions in southern U. S., ~co, and elsewhere; they' camot 00 confined 

only to peripheral regions like the Great Lakes region and California. 

We nave been concemed not only with the source, production, and dispersal 

of ragweed pollens; we have also wondered w hero all tho atmospheric 

pollen load ultimately goes. Whgt happens to the pollen that falls out of 

the a tmospherel Mr. Solomon Goldstein, a mycologist, has made proliminary 

investigations of this problem by collecting not only ra.eweoo pollen, but 32 

other species of plants that produce air-borne pollen, and exposinC them to 

conditions that would test whether they are destroyed in the soil or on 

water surfaces by f'ungus action. Pollms were gathered by allowinc mature 

mther sacs to open over paper at roomtemperllturc.. With ragweed, however, 

the flower parts ha 1 to be macerat~d with mortar and pestle to liberate the 

Erains, for reasons that will be apparent below in tho discussion of pollen 

d.i.ete.rle~ of ragweed •. When not in use the pollen was '!!ltox-edin a deEp-freeze 

in capped bottles. Ssnp1es of soil were gathered from the top 2 ern. of the 

ground and usuallY within 1i holU's the soil sa.np1eswere pl.aced in sterile 

petri dishes and covered with a layer of ca. 0.5 ern. of storile tap water. 

The pollen grains were dusted on the surface of the water, one kind to one 

culture dish, and each day microscope slides were made by touching a slide to 

the surface of the water~ staining the attached material with acid fuchsin 

and sealing with a cover-slip. The results of 140 cultures, recorded in 

terms of number of grains infected,per 100 gr~ns counted per slide, indicated 

that fungi certainly IllUst play a role in tho destruction of pollon grains :1.."1. 

the sllllil. There w as no specificity between any of the pollens employed md 

any of the fungus attackers encountered in this study; but there is a variation 

in degree to which the vario~pollens are susceptible to attack by the 

two most commonly found chytrid1aceous fungi (Rhizophydium and OlpidiUIII). 

Some pollens never showed more than five infectionsperlOO grains, while 

others were attacked totally. In general, whether wind-borne pollen erains 

land on damp soil or in the water of lakes and ponds, we can expect a high

265. 

degree of action on thom by funCi, action which will vnry in terms of the 

part of the grain affected (i.e., contents, or wall, or both) and intensity 

of attack (some species being Jilore readily attacked than others). 

The production .and diBcharge of pollon grainB fr

266. 

6. Extonsion of the Pjlltillod1\Ul1.-The pistillodium is a peculiar vestigo 

of the pisUl1ii th'Cotli""erwise ame or staminate flower; it has the fom 

of an UIIIbrolla and durine thopr1Jna1"'J opening of the pollen sacs it lies con.. 

cooled deep in the tube of the tlowor. At a poriod ot several hourS attar 

openinG of the pollen sacs, however, it extends, probably by the same mochonism 

as the pushing out of the anthers. The pistillodium 80ans to function 

as a, II sweeper" ot such pollEn grains that still remain botween the open 

pollen sacs. 

7. Withdrawal of Pollen Sacs and Clo~ of Flowera-This happens sometime 

late in the same~t"l'he l'!Ower tron;r;-rt is apparently an 

irreversible process' once a floverhas discharged its pollen, it closes~ 

never to open again. 

Previous observat ions had ind1cated the diurnal periodi,tt,. in tho release 

of pollen from ragweed plants. The process of r eleaso is more complicated 

thon that in most aeroallergonic plmts, and this explains why pollen cannot 

be colle ctcd merely '.:uremovin& flowers trom the plant· and laying them on 

paper-, as described above; apparently the processes are quite sensitive and 

require a fairly complicated series otWe rc.actioos before the anther-S8IIIl;' 

will extend and open the. !lower. •The purpose of the studies by Bianchi and 

SChwOl1lllinwas (a) to contiI'm and define our obscrvaticns; and \b) to investigate 

the environmental factors which are responsible for the initiation and 

control of the diurnal release. 

Observations dUr1ng the pre-eeaeon experimalt of 1958 continned the 

c.l1uI-nal periodicity of tho pollen release and daIIonstrated that this dehiscence 

of the pollen sacs occurred generally between 6:30 and 8:00 a.m. During 

this period. in which !lofalap~"~~)l1!red~berp was a marked drop in 

the rclati'm ·humidit1,arisoH:tn :ttm.~a~ ·and·en incraase in the· 

solar radiation. 

Prior to tho actual reloaso'ot,;th'e po).J,.f;Il,.theflower procoeds through 

a d(lVclopmental sequence whicb b~gs about theeJ;evation or presentatioo of 

the pollan flBrCSabove thec.o~olla- .This appears to be due to the elonf(ation 

"fthe 1I'l;ame,n-stalks or !flaments. The pollen sacs then break apart, exposing 

tho pollan mass. t was possible to demonstrate experimentally that 

the eXt"ension.ot .the pollen SaclLOPuld te controlled by v:B.r7ingthe tq!pG .... 

ature. TheEarterv.¢9~ proc6\S8 CQ)J.ltibo1nhi1:'l:1:t$db1~Ubattoo ottho flowers 

~treduced telnperatuJ'(ls.Thisinhlbi:t.:i0n was revensed. byexpqsureto a , 

second elevated telllp,En'ature. .. 

iy. reeuJ.at~B.tber~ati~ bI.Dr4d1'Q" BondthlilltQllPQratuJ'e ofth" ePYiJ!!On .. 

ment, 'hh6.ac.l.re:l,ElIijle o! pqu.nfrom the antJ;ler ~uld aJ.ao ltecoot1'oUed. 

Thodeh1scence pro~:l:s ~ a.~:$l1d :~t~ of the pollen eae.. 

Release of the pOllen is thus 8:t~~edby artlpi

267. 

temperature throuehout the entire period slowly increases from the temperature 

of the previous night. ContinuinG work on the production and discharge of 

ragweed pollen grains is being conducted. 

The last of the aspects of our work concemafne biology of the pollen 

grain. This is a phase that has potential medical significance in regard to 

the source of the allergenic substances-Is the allergic reaction cause by 

substance on the wall of the pollen grain, the wall of the grain itself, or 

by the livinC contents of the grain? By devising techniques to cause germination 

of the pollen grain, ar..oi mparating the living pollen tube from the 

inert wall materials, it may be possible to obtain some answers to these 

questions. 

However, difficulties have 'been encountered by pollen workers in their 

studies of Ambrosia pollen because of their inability to germinate this 

pollen in vn~. Theodore F. Boals, plant cytoloc;ist, has attacked this 

problem""In the attempt to find II suitable culture condition for gennination 

and to ~.,:llennine the effects of various facters on the development of the 

pollen tube. Much time was spent fruitlessly explorinG possible culture 

conditions before the truly limiting factor was discovered, namely that the 

age of the pollen was extremely critical. It was found that the viability 

of pollen under culture conditions very rapidly declines after the optimum 

peak achieved not long' after release from the pollen sacs. 1. curve of 

percentage germination plotted against the a ge of the pollen (i.e., the 

number of hours a fter the pollen was released frcrn the pllllt) shows 

typically a large peak at about lt hours, followed by a lower plateau continuing 

until the fourth hour. This is followed by a sharp drop in gemination 

to a bout 10%,at which point the curve remains fairly level. It j .• 

a remarkable fact that this small percentage of germinability is maintained 

over Icing periods of time, and even after a year it is possible to obtain a 

low level of gennination. The high peaks obtained on various strains of 

ragweeds from about 40 to e: per cent germination, however, are never again 

obtained, after the critical post-discharge time of It hours. It was also 

found in this study that normal species and varieties of raGWeeds all have 

a fairly high level of germination, but the. hybrid ragweed, Ambrosia X 

intergradiens, produced a mere 2 par cent of pollen tubes. 

One of the difficulties present in this research thus far is that it has 

been impossible to carry the srowth of the pollen tubes beyond one-twentieth 

or one-tenth of a millimeter. In the natural conditions, when the tube grows 

on the plant, it must Grow for as much as one to two millimeters. Thus, it 

will be necessary in our future experiments to determine means that favor the 

continued development and expansion of tho pollen tube that more nearly 

approximtes the natural condi.tdon ,

268. 

BIBLIOORAPHY 

Dingle, A. N., G. C. Gill, W. H. Wagner, Jr. and E. W. Hewson, 1959. The 

omission, dispersion, and deposition of rar:;weed pollen. Geophysics 6 

(in press). 

Garner, W. W. and H. A. Allard) 1920. Effect of the relative lenBth of day 

and night and other faetors of the environment on growth and reproduction 

in plants. Jour. Agric. Ros. 18: 553-605. 

Sheldon, J. M. and E. Wendell Hewson, 1957. Atmospheric pollution by aeroallergens. 

Progress Report No.1 (Botanical Phase, pp. 1-15). Ann 

Arbor. 

, 1958. Atmospheric pollution by aeroallergens. 

-- .... P... r-o-g..r..e-ss--;R ...e-p-o-r"l't-N ...s:2 (Botanical Phase, pp. 1..13). 

Wagner, W. H;, Jr. 1959. The hybrid ragweed, Ambrosia artemisiifolla X 

trifida. Rhodora 61 (in press). 

(Editor) 1959, An annotated bib1io&raphy of rab~eed 

--~(P"IIA-=m:'l:b:::r-=o'::sir.a:-)I"".-'7"IQ::::ua~r=tr-. Rev. Allergy and Applied Immunol. (in press). 

Wagner, W. H., Jr. and T. F. Beals, 1958. Perennial ragweeds (Ambrosia) in 

Michigan, with the description of a new, intermediate taxon. Rhodora 

60 (no. 715): 177-20~.

269. 

.rl.D",IlHclTRATIVEASPEC'I'.s 

of a 

dUNICIPAL RAGWEEDCONTROLPROGRA:l 

Israel Weinstein, M.D.· 

Former Commissioner of Health, Ne';" York City 

. Since hay fever is not a reportable diseuse, 

tne dxact number of persons ~ho suffer from it each 

year is not known, Hovrever , the United States Public 

Health Service estimates that 5% of th(1 inhabitan ts 

in the area east of the Rocky Mountains, vith the· 

exception of the Northern Great Lakes region, Northern 

NeTIEngland and Southern Florida, suffer from hay 

fever caused by the pollen of rag:reed. This means 

that over 8,000,000 people in the United States east 

of the Rockies are SUffering trom a disease that is 

oreventable, and they are clamoring for relief. Moreover, 

it is generally recognized by allergists that 

the prevalence of this condition is increasing from 

year to year. In a reuort on chronic diseases taken 

from data collected in the National Health Survey conducted 

by the U.S. Public Health Service in 1935 and 

1936, i1hay fever and asthma" stood fourth in prevalence 

in a list of chronic diseases. Surely this 

condition merits the serious attention of all officials 

concerned '7ith public health. 

In the Ne':! York metropolitan area there are t~·'o 

vurieties of r-agwee d that are commonly found. One 

is the short, d'rrarf or common rag"eed (Ambrosia artemisiifolia) 

'-'hich reaches a height of 1 to 5 feet. The 

other is the giant rag'1eed (Ambrosia trifida) which 

grows from 5 to more than 15 feet tall. In this area 

the seeds start germinating about the first -reek in 

April. The plants begin to flower and produce pollen 

during the first or second week of August. This 

process continues until the seeds are mature, which 

usually occurs at the end of September or beginning 

of October. The plants bloom ever)- year at about the 

same tLne, regardless of the extent of gr o-rtn, Whether 

they are several inches tall or have reached their max 

Lnum height seems to be of no importance. 

The ragrrecds are prolific pollen producers. 

It has been estimated that each year an acre of rag 

~eGd can produce as much as 50 pounds of pollen. The 

pollen grains are exceedingly small. It would take 

L'. u __ .... ~,,~~_ ~ ... +-'"'=,." +-" f'411 l> T.p.f'l.!'Inoon. hiost

currents and may be carried a grs a t distance. However, 

the concentration of atmospheric pollen 

drops rapidly as it is carried away from its source. 

It is not necessary to eliminate all the poller 

from the air. The majority of hay fever sufferers 

will get relief from their symptoms if the concentration 

of the pollen grains in the atmosphere falls 

below 25 per cubic lard of air. 

The rn[~Yeeds ~re ~ind pollinated annual planw 

and reproduce only by seeds. Just as soon as the 

seeds are inatur e , the life cycle of the plants has 

been comp.Lebed, and they die. The, seeds' fall to the 

-r-ound and remain there until 3D.ch time as condi ti-ons 

are favorable for their crowth. They 'are very viable 

and can remain dormarrt for as lone: as 40 years. 

EcolOGists classify plants into three 3eneral 

cQte~ories: pioneer, inte~illediate and climax vegetation. 

This natural phenomenon is known as plant 

succession. The most important pioneer plant is 

ragweed. 'Vherever pioneer plants establish themselves 

they flourish over a period of years until 

the soil is such that it can support an intermediate 

group of plants (herbaceous perennials and 

grasses). This process may take 10 or more years. 

As the intermedil. te plants grow the pioneer plants 

are forced out. The ragweed is not only a pioneer" 

it is alao n non-compe~itlve p~nt. If undisturbe~ 

the intermediate stage gives way to climax vegetation, 

such as shrubs and trees. According to Dr. Wodehouse, 

theIndians had, nO hay fever because they 

lived in the pri~meval forest or on the native prairie. 

In those early days the land was covered with 

climax vegetation. As the white man built cities 

and highways and developed farms, climax vegetation 

~us removed and much of the soil ~as left bare. 

Hay fever is naturetsreply to mants 7asteful e~ploitation 

of natural resources. 

The hay fever sufferer may seek relief in 

various nays. He may· receive a series of injections 

of specific po~len extracts to build up a 

resistance against the harmful effect of the pollen, 

or he may take certain drugs as the antihistamines. 

These personal measures are not al~ays 

effective. The individual may protect himself by 

moving to a pollen-free area during the pollinating 

season; or he may install an air-conditioning or 

pollen-filtering unit in his home. Many, if not 

most, hay fever victims cannot afford these luxuries. 

A far better way of bringing relief is 

to treat the environment rather than the patient. 

m~ .............. ~ .:14 ~nn.. o"'"" "f' t-:k", 'h"' ....h1 r'.1nA 9..4-dichloro-

271. 

ns':.' field in public health vras opened. 

came possible to eliminate ra~leed fron 

at a reasonable cost; in fact at only u 

that required for mosquito control. 

It non bevast 

areas 

fraction of 

2,4-D is a selective herbicide. In a concentr&tion 

of 0.1 per cent by weight it kills broad 

leaf plants but does no~ affect grasses and some 

other resistant plantae The herbicide is absorbed 

by the plant, transferred to the loryer stem and 

roots, causing the plant to starve. The spray 

should be ~ell mixed and applied uniformly in the 

form of a coarse drenching spray. Care should be 

exercised not to allow any of the spray to wet adjacent 

desirable vegetation. The equipment should 

not be used for any other agricultural pest control 

·'Jork. 2,4-D is non-corrosive to equipment, and nonpoisonous 

to human beings and animals. 

In 1946 the New York City Health Department 

instituted a large scale ragneed control program. 

A number of other city departments cooperated. The 

Health Denartment was the coordinating agency. It 

assumed responsibility for planning the budget and 

providing technical and supervisory guidance. It 

also carried on education and public relations. 

Several rag7eed sufferers' groups assisted in this 

part of the program. 

The Borough 

diction over the 

of the spraying. 

vised the '."Jork. 

Presidents' Offices, that have jurisstreets 

in New York City, had charge 

They engaged the labor and supe~ 

The Deparunent of Sanitation loaned the street 

flushers '.'1hich -rer-e converted to provide pO'Jer units 

for the spraying operations. The Department of Health 

and the Borough Presidents' Offices jointly undertook 

the equipning of the trucks. The Park Deparunent 

sprayed rag7eed grorying on the property under its 

jurisdiction. The Police Deparu~ent, through its 

precinct safety inspectors, mapned the city showing 

the location and quantity of rag:leed. . 

Before the actual start of the program the 

Health Department in t\"Jo trial operations found 

the t ',"Thenthe herbicide 2,4-D was applied as a 0.1% 

solution, \"Jetting about 90% of the plant foliage, 

it would kill the ':Teeds without injuring the grasses. 

Approximately 200 gallons were found to be necessary 

for one acre of rag~eed. A crew of 3 men could spray 

about 2t acres a day of scattered city lots. One 

pound of 2~4-D powder \"Jus used to make 100 ~al~ons

272. 

the chemical at that tLne to apT"roxi,nately $2 an 

acre. 

0ritics of municipal spraying programs have 

maintained that it is a waste of public money for 

the city departments to do this work. They call 

attention to laws on the statute books requiring 

property owners to destroy ragweed on their premises. 

But attemps to enforce these laws have not 

only been costly in the time consumed, but in lar~ 

measure ineffective. Many pronerty owners could 

not be located. Others, in spite of instructions, 

destroyed the weeds after the pollen had polluted 

the atmosnhere and seeds had fallen on thegrou~d. 

Campaigns in the past to eliminate ra~"eed by cutting 

and pulling generally were failures. Wherever 

the soil was disturbed, dormant seeds were given the 

opportunity to germinate. Thus in a short time 

new plants appeared which pollinated and produced 

more seeds. There is no doubt that1n any city-wide 

campaign for the destruction ot ragweed the cooperation 

of the property owners should be sought. 

Effective help can often be obtained. from those 

who live on their property or are otherwise using 

it. But the bulk of the ragweed in a large city 

is on vacant lots, along highways and in alleyways, 

and this must be destroyed by the municipal authori 

ties. 

Many people believe that a program for the 

elimination of ragweed within a local area is futile 

unless similar programs are earn ed out by 

neighboring communities within a radius of at least 

50 miles. This is a mistaken idea. It has been 

shown by ~'fodehouse and others that ragweed pollen 

quickly loses its power to irritate as it travels 

through the air. In other words the closer the h~y 

fever patient is to the plant the more irritating 

its pollen. The pollen that is blown for 50 or 100 

.niles is a negligible factor in bringing on sneezing 

and the other symptoms of the disease. This 

explains why t~ere are resorts to which hay fever 

victims go for relief that are within comparatively 

short distances from areas whe~ ra~~eed flourishes. 

Of course, every effort should be made to induce 

ne.1ghboring communi ties to eliminate r agweed in their 

o.vn territory. But the fact that some of these 

comnunities might not react favorably to this idea 

is no excuse for a city to be derelict in its duty 

to its citizens. May I repeat, it is the local 

growth that is the important factor in initiating 

the symptoms of hay fever.

273. 

AS in the case of any other public health 

program careful planning and adequate supervision 

are the factors necessary for success. Each year 

the accomplishments should be carefully evaluated, 

and the over-all plan modified in accordance With 

the lessons learned. If the same care unO. attention 

are given tor~gweed destruction as are given 

to other public health campaigns as for example 

mosqui to control, there is no reason why ragl'7oed, 

and with it hay fever, should not be entirely 

eliminate'd from this part of the ,"vorld. 

-Refe,rences 

1. IIEssentials for the Control of Ragweed" by 

Israel Weinstein and Alfred H. Fletcher, American 

Journal of Public Health, Vol. 38, May, 1948. 

2. "Planning and Organizing a Rag:leed Control program" 

by Pb,ilip Gorlin, Proc:eedings of the Northeastern 

Control CqnfeBence, Feb. 13,1948. Publishedby 

Rutgers Universi ty College of Agriculture", New Brrms 

~ick, N. J., pp.166-~73. 

3. "Weeds, 'las te and Hayfever 11 by R. P. ~ilodehous~ 

Na.turalHistory, Vol. 43, No. 3,1939. 

4. "Procedures of Promoting and Operating Ragrreed 

Control Program" by Alfred H. Fletcher, Nevr Jersey 

state Department of Health IIpublic J;Iealth Nel"s~ 

Vol. 36, No.5, il1ay 1955. 

5. "A Revie','l of Pollenosis and the Role 0 l' Weeds" 

by 'V. C. Spain, Public Health Repor'tf:i, Sept. 1953, 

68: 9', pp, 885-889'~ 

6. IIHay Fever; An Evolving Problem for Sani taria:rs II 

by John H. Ruskin, The Sanitarian, Vol. 20, No.2, 

Sept.-Oct. 1957.

274. 

Vhat Garden Clubs Can Do 

Possibly because the word "garden" is part of the name of our institution, I 

have been given the topic "What Garden Clubs can do in the matter of weed control. " 

Actually we have no more contact than any other group with the machinery of Garden 

Club operation. BUT, the fact that there are hundreds of thousands of Garden Club 

members over the land, and the fact that they have taken up every worth while cause 

within their reach that would make for better community living, makes it reasonable 

to assume that Garden Clubs can have an important role in certain ph!ses of the weed 

control program. 

If we reduce the weed control problem to its simplest terms, we can say that for 

well over a decade we have had Imowledge of the technical means of destroying unwanted 

plants, and a number of communities have implemented progran:s for noxious 

weed control. The greatest weakness, as I see it, is that fact that most people have 

absolutely no idea of the problem, much less its control. If public opinion is to be 

mobilized against tolerating plants that are detrimental to health, we must do more 

than release a few newspaper articles. It has to be a grass roots project. To make 

it so, every community organization might have one or two ten-minute talks as a 

part of its program each year. The first talk could be devoted to demonstrating the 

offending plant or plants, explaining how they can be simply eradicated - whether at 

the volunteer or paid personnel level (depending upon the size of the community). 

Such instructive talks would require a battery of people to carry out. "1!I~y recommendation 

would be for any state where there is to be a serious effort for noxious 

plant eradication, to enlist the good offices of state Garden Club organizations. They 

could be asked to contact all their clubs and to set up the machinery for a grass roots 

educational program. The information put in their hands should be carefully worked 

out, and Garden Club officers should be asked to limit their requests for speakers to 

those who can do a convincing job in a brief span of time; ten minutes might be the 

top limit. There would be little point in talking the situation to death before it starts. 

If a typical Garden Club could mobilize a half-dozen good speakers, either members 

or non-members of their respective clubs, they could contact all other civic-minded 

groups in the com.munity, whether made up of men or women, and ask for a small 

piece of a program at the appropriate season. 

Garden Clubs can provide coverage that can be had in almost no other way 

unless at great expense. And I might add that volunteers are often more effective 

than paid personnell So, why not invite the Garden Club movement to provide the 

network for spreading information? This is only one link in the chain, but it is a very 

important one. 

George S. Avery 

Brooklyn Botanic Garden

~ POLLUTION2!.m ~, ~ CANBE~ ~ ill 

275. 

~ RELATIONSASPECTS 

B,y Charles N. Howison, Executive Secretary of the 

Air Pollution Control League of Greater Cincinnati 

Good public relations are vitally important to the success of any 

program to prevent and control pollen pollution of the air from ragweed. 

Good public relations helps to get needed legislation. Good public 

relations, and especially effective pUblicity are needed for a continuing 

program of education. Weed control is a matter of education of the public, 

and of children in particular, through illustrated booklets, posters, radio 

talks, exhibits, special campaigns, etc. 

The eradication of weeds is expedited through good public relations. 

The general methods of control of noxious weeds include eradication by 

cutting, digging out and mowing, and finally - the best and easiest method 

spraying with a herbicide in solution. 

In Cincinnati our theme is lIGet Ragweed·Before It Gets You". Our 

program is to persuade and motivate people to destroy weeds, particularly ragweed, 

because the pollen from ragweed is the principal cause of late summer hay 

fever and asthma. 

Through the continued efforts over the years of our active Hay 

Fever and Weed Control Committee, effective weed control ordinances have been 

passed by the City of Cincinnati. Our committee insists that these ordinances 

be enforced. 

MUNICIPALCOOPERATIONIMPORl'ANT 

A good example set by public officials in the enforcement of weed 

control ordinances helps the overall. program to abate pollen pollution of the 

air. It is especially important that the municipality wage a continuing battle 

to destroy weeds growing on city owned property, and along streets and highways. 

This gives the private property owner a good opinion of city enforcement 

officials and results in a greater desire on the part of the public to 

cooperate. Good public relations does nob require a million dollar budget. 

However, it does require an effectively planned enforcement program efficiently 

carried out. 

The Cincinnati Weed Control Ordinance #316-1953 provides for notice 

or warning to be sent property owners where weeds are growing in violation of 

the ordinance. This first step is taken by the Police Department. During 

1958 warning notices were sent to 1686 property owners involving 2101 locations. 

Citations were given to three property owners. During the year 1958 

the Police Department reported 14 city owned locations to the Public Works 

Department for the cutting or sprlqing of weeds. The splendid cooperation of

276. 

the Cincinnati Police Department in notifying owners of private property where 

weeds are growing in violation of the ordinance has been most helpful in 

obtaining citizen cooperation. This program was supplemented with educational 

leaflets provided b,y our organization. 

During the year 1958 the Cincinnati Department of Public Works had 

a total expenditure of $37 1300, for the killing of weeds along street right-ofways 

and on public property. The program required a total of 8700 man hours, 

which did not include the many man hours of the Work House inmates. 

The weed cutting routes were completed four times during the season 

or the equivalent of approximately 1200 miles of roadway. Weed spraying along 

the same routes were completed once and repeated where necessar.y. The control 

of weeds b,y spraying required the use of 1780 gallons of Dimethylamine Salts of 

2.4D, four Lbs, acid per gallon. In addition the Department of Public Works 

destroyed weeds on ten parcels of private property as provided in the city1s 

anti-weed ordinance. A total of fourteen parcels of private property were referred 

to Public Works b,y the Police Division. 

I believe it is important that you know of the good example set 

by the City of Cincinnati itself in our program to reduce pollen pollution of 

the air. This splendid support is an important factor in obtaining citizen 

cooperation and helps greatly to reduce the suffering of persons allergic to 

ragweed pollen. 

Wework for cooperation of the public through an educational program 

which makes all possible use of all channels of communication. This 

includes press 1 radio and TV, pamphlets 1 booklets, public talks and appearances, 

posters and exhibits. The services of all interested groupsl including 

civic clubs l garden clubs and PTA's are solicited in the annual campaign. 

~ RELATIONS 

In building good press relations it is important to become acquainted 

with members of the working press - managing editors 1 city editors 1 

columnists, reporters and photographers. A good way to get acquainted is to 

invi te them to see the work you are doing - the before and after effect. They 

are interested in getting ragweed control news since it is good news for the 

communi ty • 

The editorial good neighbor policy pays dividends. The press is 

close to public opinion and when trouble is brewing a cooperative press will 

ask you for an explanation. Whenthey do - 

Give them all the information you can consistent with the interests 

of the principals involved. Newsmenare under pressure to get facts and they 

appreciate cooperation. Generalities and evasiveness are road blocks to public 

relations and should be avoided. 

PUBLICITYRELEASES 

Directed to the right editors, the neater and simpler the news release 

appears, the more chance it has of being read and put to use. A title

gives the editor a clue as to contents, although it probably won't be used. 

A standard size white sheet Bt"x 11 11 , and double spaced typing helps. Your 

name and title should be at the top. The date written and day to release is 

required. 

para 

The who, what, when, where, why and how belong in the first 

graph. Details can follow. These IIdo'sll and Ildon 1ts ll help. 

IIDolSll 1. Put in all the pertinent facts. The editor will cut thi:lstory. 

2. Learn when the paper goes to press and get in story a day or 

more ahead. 

3. Get the names, dates and statistics complete and correct. 

IIDon'ts II 1. DonI t submit a story after the event takes place. 

2. Don't ask the editor to print a story as a favor. 

3. Don't editorialize or t~J to give advice to the pUblic. 

Whensubmitting photos have them made by professional photojournalists. 

It is not necessary to wait for perfection to tell the ragweed 

control story. Progress is good news. 

~~ TELMSIOO 

277. 

The story of pollen pollution control is as important to radio and 

television stations as it is to newspapers and magazines. The ability to obtain 

coverage on local radio and television stations depends on the efforts of the 

local RagweedControl Committee. Experience has shown that local stations are 

interested in the local story and therefore every effort should be made to keep 

these stations fully informed of local activities. 

The first thing for the local committee to do in order to gain time 

on radio and television is to ascertain the names, addresses, and telephone 

numbers of the program directors and public service directors of all radio and 

television stations. This can be done quite easily by a telephone call of 

inquiry to the stations. 

A letter should be sent to each of these directors stating that the 

local Weed Control Committee is interested in assisting the directors in their 

efforts to tell their listeners and yours about weed control activities in the 

area. Insofar as possible, the looal committee members should discover what, 

if any, programs on the local stations are devoted to topics of community 

interest. It is evident that these are the types of programs on which the Weed 

Control Committee story should be heard. Once this information is obtained 

contact can be made by letter directly to the moderators or producers of such 

programs. 

Any news releases which are sent to local newspapers concerning weed 

control activities should be sent at the same time to all news desks of the 

radio and television stations in the area. There is no need to change copy for 

news programs on radio and television.

Your committee representative should not expect that the local 

radio and television stations are waiting with bated breath for his entry into 

the public relations field. Nevertheless, he will find that if a good story is 

ready, radio and television, like newspapers and magazines, will want to do 

something about it. You may believe that you have an excellent story, and at 

a particular time the program directors may feel otherwise. Since they are 

doing you what is in essence a favor, you should accept their refusal gracious 

1v and keen tl"'ll'in tr; 

278. 

Experience has shown that most radio and television stations prefer 

"live" to canned programs, that is, programs recorded somewhere outside 

the community, or scripts designed for use anywhere without a definite local 

angle. They much prefer an unrehearsed and fairly spontaneous interview type 

program which is clearly designed for local consumption. 

Where a station (and this will usually be radio) has programs of 

short duration, 1,minutes or less, they may prefer the speaker to deliver a 

talk without a question period and with only a few introductory remarks and 

closing remarks by a station announcer. Again it must be stressed that here, 

too, the local story should be emphasized although there is nothing to prohibit 

references to what other communities are doing in the field of weed 

control or pollen pollution cc.ntrol. 

SPOTANNOONCEMENTS 

Much success for local control programs has been found with what 

are known as "spot anncuncemenba;" These are usually 1, to 20 seconds in duration 

and sll-ould be designed '00 tell the local listeners that the committee 

seeks their help in the fight for weed control. Local radio and television 

stations usually are capable of giving time for such brief announcements. These 

should be typed, double spaced and at least two or perhaps three copies of such 

announcements should be sent to each station. Television stations usually like 

some sort of art or photographic. material with these announcements, but this 

is not absolutely necessary. It should be made clear that the language may be 

changed to suit the ctations' requirements and that the suggested dates and 

times of broadcasting are left to the discretion of the station. 

~~ANGELS? 

In many areas of the country large corporations of the public service 

type, such as utili ties, have regularly scheduled programs on radio and 

television. Employees of such corporations m~ be members of your Weed Control 

Committee. The commercial time of these programs iSi of course, devoted to 

announcements which havena comparison with a company that produces a product; 

they have, basically, good.-will in mind. There is an excellent possibility 

that from time-to-time, perhaps while discussing its own efforts in the field 

of weed control, such a corporation will be willing to devote some commercial 

time on these programs to public aervi ce announcements from the local Weed 

Control Committee, or enforcement agency. Therefore, close contact should be 

made and sustained with the director of community relations or public relations 

of such corporations.

279. 

The initial contact is often the toughest and what you do today 

may not bear fruit for some time. But - once the contact is made and once the 

radio and television stations know that you are available and want to be helpful 

most of your job will have been accomplished. 

In summarizing, these are the steps that must be taken to obtain 

radio and television "ime: 

1. Accumulate a list of all radio and television stations together 

with the program directors and public service directors. 

2. Determine all public service programs which are on local stations. 

3. Contact all program directors, public service directors and 

moderators or producers of public service programs. 

4. Make sure that all radio and television stations receive at the 

same time whatever material you are sending to newspapers and 

magazines. 

5. Do not offer "canned" material unless the radio and television 

stations specifically say they will use same. 

6. Contact utilities which have radio and television programs. 

7. Send spot announcements to all radio and television stations. 

8. Do not be discouraged. 

SERVICECLUBS~ 

CIVICORGANIZATIONS 

Public talks and appearances are important. There are many organizations 

whose support can be enlisted, depending upon local factors. Often a 

service club, such as the Kiwanis or Rotary, will adopt an effort of this kind 

as a part of its program, If' the employees of a particular factory are significantly 

affected qy hay fever, it is possible that both management and the union 

can be interested in efforts to overcome the cause. A good deal of missionary 

work must be done among the natural leaders of the community. They must be 

sold on the necessity for a control program if the organizations they lead are 

tn function effectively. 

Publicity is the product of action. With guidance you can initiate 

and encourage the action which produces the publicity. Any action to bring 

about better community understanding of a problem and to prompt community action 

to overcome that problem is sound pUblicity effort in its broadest and best 

sense. It is information with a mission. It is communication. It is good 

public relations. 

An interested, enthusiastic$ dedicated committee will achieve more 

results than a front page story in the paper every week without such organizational 

effort. The front page story is read today and forgotten tomorrow or 

the next day. But the dedicated committee makes its impact felt every day in 

"nm'" v ..v~ Tt. "",t." T'I",nnl., to th'inkinlZ and it lZets them to act. It won't allow

280. 

them to forget. The media of information takes their place as tools to supplement, 

from an informational standpoint, the organizational work of such 

groups. 

In securing the active participation of groups and media, it is 

helpful if you can find among them persons who are person~ subject to ~ 

fever. It is desirable to identify prominent persons, wherever possible, who 

are personally affected by hay .fevo,r because they are receptive to efforts to 

eradicate ragweed. 

I have found it productive to send news stories directed to the 

attention of the chief editorial writer o.f the paper as well as to the city 

editor. For reasons of space or personal preference, the copy desk may on 

oecasion leave out the paragraphs you would particularly like the editorial 

wri ter to see. We have seen helpful editorials result from sending occasional 

news stories directly to the editorial writer. 

PROCLAMATIONS 

It the organizational effort has been well planned, it should be 

followed up with requests for proclamations to mayors and to the governor. All 

such requests should be submitted at least a month before the period .for which 

they are desired and they should be accompanied by a suggested proclamation. 

Many such requests are turned down in executive offices because they are received 

at the last minute and there is not time to consider them in relation to 

other requests for the same period of time. Governors and mayors receive as 

many as five different requests to observe the same period for different purposes. 

Other things being equal, the only fair policy the executive can follow 

is to consider the meritorious requests on the basis of first come, first 

served. Be sure your request is submitted well in advance, that its purposes 

are clearly stated, and, if possible, indicate that a substantial number of 

citizens is asking for it. 

As you know, June is National Ragweed Control Month. This project 

originated in Cincinnati with the Air Pollution Control League. It is one of 

the many Special Days, Weeks and Months recognized by the United States Department 

of Commerce and the United States Chamber of Commerce. Its purpose: 

liTo control the growth of ragweed because the pollen of this weed is the chief 

cause of late summer hay fever and asthma ll • In 1958 June was proclaimed as 

Ragweed Control Month by the governors of twenty-two states and by the mayors 

of maqy cities and towns. 

Another suggestion is not to ignore community newspapers. In Cincinnati 

and Hamilton County we have two daily newspapers. We also have 25 

community papers published in towns and communities in the area. Circulation 

ranges from 4,000 to 15,000. These pub'ld.catdons can be very helpful. They 

should receive notices of all meetings which are going to be held in or near 

their respective communities. They should also receive editorial background 

material and educational material distributed through the schools and to the 

homes of citizens.

281. 

CONCLUSION 

Publicity is not an end in itself. It is an important part of 

good public relations.· It is a means to an end. Its effectiveness can be 

measured by the contribution it makes to the attainment of overall public 

relations objectives. 

In the objective which we are presently considering - pollen 

pollution control - publicity will be based on the control effort. If the control 

effort is sound and sustained, there will be ample opportunity to secure 

helpful publicity. The degree to which the opportunity is seized and utilized 

is a measure of theresourcetulness of the informational specialist. 

Public understanding. of weed control work to reduce pollen 

pollution of the air is a deSirable objective. Public relations consists of, 

first of all, doing the right thing and letting people know about it. The use 

of modern good will building methodS speeds the process and widens your 

horizons. 

It is imperative for the members of the local committee to be 

expert in providing accurate and understandable information to the community 

and the public. To be expert and willing requires action. 

Paper presented at the Northeastern Weed Control Conference - 

Public Health Section, NewYork City, January 8, 1959.

PUBLIC HEALTH ASPECTS OF WEED CONTROL 

By: Floyd I. Hudson, M.D. 

Executive Secretary 

Delaware State Board of Health 

Presented at the Panel Discussion. "Pollen Pollution 

Of the Air, What Can Be Done About It" - of the Public 

Health Section, 13th Annual Meeting of the Northeastern 

Weed Control Conference, in New York. N. Y., on 

January 8, 1958 

Many of us were fortunate in having the opportunity to attend the 

National Conference on Air Pollution called by the Surgeon General of 

the U.S. Public Health Service in Washington in November. Much of 

what I will tell you today was also discussed at the Washington conference. 

The existence of particles in the air, derived from plants and 

animals, is now generally considered a part of the greater problem of 

air pollution. We must. therefore, consider the continuing of the attack 

to remove such harmful particles as ragweed pollen as a part of a total 

air pollution control program. The efficacy of eliminating these substances 

from the atmosphere has already been demonstrated by the many 

programs developed, chiefly in official agencies throughout the country. 

Organizations such as your own • and national organizations with the 

same purpose. can also play an important part. 

The effects on health by many products of vegetable or animal 

origin have been known to medical science for many decades. The 

association of hay fever with ragweed pollen was described more than 

85 years ago. There are many things which can be accomplished in the 

field of weed control, but such accomplishments to be practical and 

effective must include the efforts of many disciplines outside of health 

itself. 

The great amount of unnecessary illness and suffering from hay 

fever and contact dermatitis of weed origin has been fully described to 

you many times at previous meetings of your conference and in the 

literature. It is not necessary to further elaborate on the actual and 

estimated statistics of this great public health hazard at this time. To 

minimize or eliminate injury done by ragweed pollen and poison plants 

to persons sensitive thereto. public health agencies and the medical 

profession have tried the following methods: 

--

1. The prevention of these diseases by the elimination of the cause; 

namely. the removal of pollens or offending substance from the 

environment. Two means are used to accomplish this: Firstly. 

the destruction of the weed from which the pollen emanates. This 

is the practice most commonly put into use by public health and • 

other official organizations. It is applicable to fairly large areas 

and should be a total community effort. Secondly. mechanical 

devices are frequently installed in homes or buildings to remove 

pollen and other particles from the local atmosphere. This often 

provides ·relief for individuals suffering from air borne causes of 

allergy. It is not practical except to control local small areas. 

2. The desensitization. with small doses of antigens. of individuals 

who are susceptible to the particular plant substance which causes 

the disease. This process is one which requires special medical 

training and experience. It is dangerous and should be used only 

on the advice and under the supervision of a qualified medical 

practitioner. Two types of antigen preparations are currently 

being used: (a) preparations for hypodermic injection; and (b) 

preparations for oral administration. Good response to this kind 

of preventive treatment has been reported. but results show it is 

far from 100% effective. This method is applicable only to individuals 

and is not advised as a public health procedure. 

3. The treatment with appropriate drugs (antihistamines) of persons 

who suffer with symptoms caused by a specific pollen or plant 

material. This is also a medical procedure and should be used 

only under the supervision of a physician. It is not ordinarily 

employed as a public health practice. . 

All of the three methods above mentioned are used with varying d 

degrees of success; however. I believe that all of us would agree that the 

elimination of the weed causing the difficulty produces the best and longer 

lasting results. It has been demonstrated by past experience that the 

destruction of ragweed and poison ivy by means of chemical sprays is both 

economical and effective. It is clear. therefore. that a program which 

determines the where. the what, and the why - as well as the measure of 

pollen in the air - should be given prime consideration. In geographic 

areas where air pollution programs are in force. the identifying and 

measuring of the pcllens can be part of the total program of defining and 

measuring the pollutants in community atmosphere. 

Public health persons throughout the country have worked diligently 

on the elimination of many diseases. utilizing the epidemiological approach.

which is also applicable to weed control. This approach is well documented 

and needa no further explanation at this point. There are many textbooks 

and papers available on this subject. 

In studying the possibilities of alleviating hay fever and contact detmatitis 

by mean. oLcontrolling the weeds which are the basic cause thereof, 

it appears that we are faced with a goal which, though difficult, Is indeed 

attainable. Almost any officially organized political unit should be able to 

develop a program in this field. 

In order to implement a successful weed control program, there must 

be a coordinated effort on the part of all agencies involved. At the State 

level this would include the Agriculture Department of the State "University, 

the Highway Department, State Department of Agriculture, State Health 

Department, and other organizations baving to do with conservation a.nd 

economic development. It is clear that harmful wee"de may, from a practical 

and economical point of view, be eliminated. The benefits to the 

health of all people will more than repay any community for the effort put 

into the reduction or elimination of these pollutants. Persons who have 

suffered from these causes andbave been relieved by. an effective program 

will be grateful and supporting friends for life. 

I would like to stress at this. point that no one agency or person can 

successfully solve the hay fever problem in any community. The combined 

efforts of a large number of agencies and persons is essential. Administrativelytbis 

can be accc);tnplished by the formation of coordinating eemmittees. 

special councils which include key personnel from all agencies, 

and other interested groups. Liaison between all groups must be constantly 

maintained; however, one agency must have the authority to direct the 

entire operation. following agreement which come. from coordinated 

planning of all participating groups. 

I would also like to emphasize the importance of good public relations 

and general education as procedures to be used in developing knowledge 

and understanding which will be beneficial to any program. Public health 

educators in health department. can assist greatly in the development and 

operation of weed control programs. 

Detailed facets of this problem which touch upon disciplines other than 

health have ~t been discussed in this paper, but are well covered in the 

subject matter of this panel IP,n

RAGWEEDCONTROL 

THOMASJ. MCMAHON 

The most important aspect in a rU~ieed control 

pro~ram is public relations. Good public relations 

is a forthri3ht, truthful presentation of all the 

facts relating to a project for the purpDceof creating 

understanding. Failure to respect this requirement 

in matters dealing with projQcts affecting 

larGe areas of the population exposes the endt'3a.yor' 

to the loud voice of the uninformed. 

It was Dr. Dona.ld Schallock of Rut3QrS who 

pointed out last year when the spraying for the ~ypsy 

no th ended in the courts, "It just Boes to show that 

nouever good a project mayvbe , it must first 'begin 

',;i th a campaign to inform the public. II The courts upheld 

the U.S.D.A. men in their project, 'but it \,jas a costly 

and injurious action. 

Perhaps the most important function the Public 

Health Section 6f this Conference has porformed has 

been to afford an opportunity to 'bring to liGht and 

to develop the facts on hay fever. It lias here four 

years aGo that F. Wellington Gilcrease, thffi1 of the 

New Yorlr ;:ltate Health'Department and nov of the 

University of Florida, raised the question of the 

value of a pollen count as the index of the severity 

of a hay fever attack. Concurring \'ii th him \1aS another 

hay fever sufferer, Alfred Fletcher of the New Jersey 

Health Department. At that time t~ey made two observations: 

1- A pollen count aoes not afford an accurate 

ind~c of what the reaction of t~e sufferer 

has been. They could not explain this 

inconsistency; they merely affirmed the 

fact. And 

2- A noL'len count is not a forecast, ~)ut 

a report on what has ha~Dened. It is 

not lilre a weather forecast, but rather 

a re')ort on \'Ihat has be en , It confims 

a condi tionj it sUGgests no \iay to avoid 

the condi tion. 

TriO years ago the tests of a r:r. I'otts of 

the U. 3. D. A. from NeViHaven uer-e re)orted. r:», 

Potts had stated at a meeting in 3pl"ing Lake , IT,. J. 

that ~1e h a.d been unable to produce an alle1:'3ic reaction 

285.

286. 

in tests on hL:self us i.ng ')011611 thr-e e dc.y s old. 

"I'olJ.en," said ::1". Potts, "ex~)osed to n:l.r and sunli[5ht 

for three days "\,ill not produce an allergic reaction." 

Dr. Pee G. i'Todehouse, then of Led ez-Le Labor-a to r- 

ies, save su~port to Mr. Potts, though he ventured to 

state that that it is necessary only Ulat pollen be 

eJ~::;ose(l to air. He stated, "Pollen eX·,losed to air 

overni.:;ht \";ill lose half its po t ency ," 

ThUS, came to light a possible anaver to the 

observations of Gilcreas and Fletcher. And the 

question aros~: Does a pollen index consier the ace 

of the pollen co"nted? If a hay fever sufferer has 

had a light attack on days When the pollen count 

was high and, yet, a severe attack on tfi day~' When 

the pollen count vraa 10'1'1, the simple eJ~')lanation 

lies in the !:nO\';ledge 3ained by Po t t.a and 1Jodehollse. 

The full ansv er c anno t be "\H'itt en so simply, and it 

is interestinG to note the.t furt:ler research is l)eing 

mad e on this SUbject. • 

But this sim~le but important clue merits 

its place in this business of information, for it 

has also been stated here that a N'·Cljeed control :.Jro 

Gram is useless. tlPollen has been found t"\oienty and 

thirty miles out to sea," said SOJ'!le. tl1'1hat good does 

it do to control r-a..gweed here on13' to have mor-e 1=011811 

carried in on the viind?" There is eve1 indication 

1Y 

nov; tllat the f'r-e sh er- the pollen, the: more allergic 

a ev er-L ty of the r-er.c t.Lon , The nearer the re,gweed, 

the ::;reater the d2.nger. The greD,test benefi t 

expected froD the ragweed control r;la 1 be 

pro~ram in one s 

i~Dediate locality. 

It vias b er-e , too, that it ua s estiraC',teel ti1.at 

up to 65;; of all rU(3"\';eed 3ro"\iS a.Long the siele of the 

.~"Of\O in the Northeust. It i';as here t'lat it lias 

agreed that up to 10 per cent of the peo;:le suffer 

from hay fever. (Thia estimate has been stated from 

as J.ow as five ~el' cent to as hi::::h as fifteen per cent.) 

It "as here at these nee t i ng s t~l.at at: ention 

i.a s called to the survey of the U. 3. Public Heal th 

aurvey of 1936. It was the Public He8.lth Officer of 

3inS'lanton "\'iho called attention to this survey. Out 

of it cmae these fiGures:

1- At the end of 25 years, of 100 people 

h~vinr, hay fever, 65 will have sone into 

a athraa , 

2- Asthma totally incapicl tates more 2,eo1,1e thr.n 

cancer and other ~elated tuwors. 

FOUl' year s ago Dr. l!iriam Sachs presented 

1;:nl.t is_ still toc1ay a medical dcc t or ' a finest analysis 

of t~le pr ob'lem for the public helat:1 officer and t:1e 

~Jubl:_c official. Dr. Sachs l;ent beyond me~e statistics 

~nd step by step establi~~ed two main yoints: 

1- HC.y fever is a public health probJ.em. And 

2- A ragweeu control proGram is the most 

fe['.sible method '{Ie have at this tiDe to 

attac1: the »r ob'l.em, 

AmDl1,3other things waich :lc.ve been develo'led 

r.t these meetinGS 'l'i111ch fall into this factual 

data one needs for a public relations pro(3l'am 1:ere: 

naOieed grm'is only in disturbed or denuded soil. 

Thou,3h, for this reason, l'aC;i'ieed has 1Jeen called 

a pioneer pJ.ant, there is acr-e reason to belive 

it 'l'iould be mor-e aptly called a vandal; for it 

has ~Jeen observed that 1-;hen raC;lleed is sprayed 

and 1:illed, other plan'\;s Cluiclcly grol'l. A ~:ey to 

observed fact nay be found in the discover:' of 

the B1-iedish botanist, Osvald, who in 194-7 

pr-ov ed t:lat the r-ea son _the rape seed 1-iill not 

":ex'lTIinc.te in a stand of r-ed fescue is because 

the roots of the red fescue exuds t e a Ci)Klical 

lih:l.ch inhi11i ts the germination of the rape seed. 

This ua a tIle first time in the ;1_isto~y of :Jotany 

that it '{las proved t:1at roots do exudate cu end ca'l.a 

1;>1ch are gr0'1th inhi11i tors t-o o thez- plants. 

(:'T ,1.:TT G~~01iTE 3ill3TLlTCES 'Jy ~r. L. J. Audus) 

One should oi'iell for a r,lOr,le,:t on the3e above 

»o Lnt s , 1",le1'e is a bend ency to look Vi1th alarm ut 

any move to tre2.t any plant. It is 1rll,ortant tbat 

e1eo';J.e '~nO\"1 all about rq:;weed and so\e-0'_,in::5 e.bou t 

the 1-1[1,yt:_lat the exudations of 011 e pJ.D.l1. t' s roots 

\"iill 1n11ibi t the sermination 01' GJ:"'oi'ith of another 

seed or pJ.ant. Garden clubs pal't1culC'.rly ar-e 

conc erried 1;1th l;hat ha1)1'enS l-jhen one 311ra.ys, and 

they are to be conn ended for their interest a.nd efforts 

to ))rotect our flol-iers. 3u'(, these menber-a are not

288. 

o')oseo to C'. G"'() pr03ram. The" are ov-o aec to bad 

proSI'O'",,'s. I CM f3ta to v;i th c. c e)1te.i'1 e::J?eri enc e that 

!ile?l~JerS of 0'.'1" G2.rden Clubs "ielco.]e corc-letei:lfoX'l11C. 

tion on fj110l;th. Osvaldls discovery opens e. iJeli door 

of scientific l~nOi';lcdge, begins o. nev chapt.ar in the 

f~sc1n~til13 story of nature. 

You r,lay recall it \vG.8 :;)1". F0::J3 of Penn ay Lvard.a 

\.1'10 }_e2.1'neu t:lat only 65 per cent of the ue ed a of 

the Horthenet ['.i'e native; 35 per cent £11'e foreign, 

and t'..l:"S Y)e1'ce~lta~'e 1s by species. In vo Lurm , the 

foreicn \ieeo.s have almost outnumbered the D£1.tive. 

To those viLlO";6:'e concerned abou t distur"'::JinG ·Jur native 

roadside floviers, Dr. FO~:;1 s studies come as SO!Jethinc; 

of ~ shock. The disturbance is already here, the 

disturbailce of foreign invaders. OUr native l")lants 

are disa')lJ6c':.ring. 

If nov; lie consider for a monent, the im,lications 

of Osvc.ld I s di scovery abou t roo t exuds.t rone , 

\ie ui}l lJeGin to see no« il!F'ort.ant it is to include 

this information in any vleed con t.no L IJr0C;l'am pubJ_ic 

relations. We 0e3in to see that the Vigor of the 

we ed s frJm EDro'-e, Asia, and elseir;llei'e ,'lay be really 

ch erri.e a Ls rr-on their roo ts vi·...Lch are Lnh 1bi ting 

our llc,tive l"_ants. 

I re,:ember s€veN.l years D.Go visi tine; at '.Tashill::.~tolll s 

CrosstGI3 in Nmi Jersey an ar-ea the Ne\'i Jersey Garden 

Clu')8 had devoted to the :,JresGrvati,)n of our native 

f'Lov er-s , This 1'i8.S ,Jefore vieed r.prays. It "ie.S an 

interestinG d,'.y, and I founa r,lyself l'i011derin3 ';:1:' j t 

lias the.t these ilutive flovlers liere disC'.l)pe"lrin[5. 

llhat c ouLd it be? ~:aybe ::r. Osve.1CJ he,s

a ap ec t a of ~,eec1 con t ro L 1,ork. 

Auuubon 30cieties are ano th er- ;;ro~):,em. So 

also are Conserva.tion and Sports"en's Clubs. T~1.ese 

')eo;':.e are all fine 1'eo;)le and smc ere , They lic.nt to 

do the riC;',lt t'l}.ng. But the d1fficulty 1s that they 

are all confused liith all the oh enf.c ake bein3 tnroun 

at them. T~lo.t indicates furtl.ler lihy a :)ul)lic relations 

1'ro(;ro.m 1s so im~)ortant. It is not so much that one 

"il sh e a to tell soriebody somethin3; it is tl.1.at ~)eo')le 

i.an t to lmou , licnt to be told, uan t to cooperate in 

an intelli3ent way. 

~'lese srou'ls ar-e concerned Ii t'.l t'1.e effect of 

:::r01;t~1 c on t.r'o L programs 011 l'i11dlife. The most 

inrv)rto.l1t t'linG to make clear to then: 1s u e ed control 

~at€r1als used 1n selecti~e control are not noisonous. 

~lhen ,'i01'l: ,·i2.S :)eLl(j done 1n New Yor~: State to secure 

clarif1ce.t10n of County Lau 224 to l;erDi t certain 

\rieed :-::1.rayin3, r:r. Zemlansl:y, 1:1'. Gor11n, and I 

290. 

:~Te reJo.ted to t~lese u en that El.t the Boyce-TlloI11"lSOn 

Ineti tute in Yon:~er8 in the ev.rly fOl'ties, Drs. 

Zimner,mn. and Ei tchcoclr ":ere e~~plal'in3 the various fields 

of ch en Lca Le in e ear-ch of insecticides, 1111 ticides, 

[Cnd fun::.:icioes. In the course of their tests, they 

tried 2,4-D. They'learned that til01!Gh 2,4-D l';0111d not 

l~ill 11ites, funSi, or insects, the material stimul::>.ted 

tile ::;r01';til of the l')J.ants, improved their rootinG, 

and 3ener2.lly affected' the gr01ith char-ac ter-Lat.Lc a , 

T'.ley d i scov er-ed tllat 2,4-D possessed 0.11 ths ch8.ro.cteristics 

of a na" tural 1Jlant auxt.n , So im;')ortant did 

they consider t~lis discovery that they ,;rote Co pal)el' 

on it. Le.ter it lias discovered tilat used in stroll::;er 

amount.s , 2,4-Il l:1:1,led br-oad Lea f ,';eeels. 

We est1:'.blished the fact that the na t er-La.L had 

been rejected e.s a niticide, fun3icide, and insecticide 

before it ,'jas Lear-ned of its use a c e- Sl'm';th control 

c 1'.er,lico.l. 1fe covered also mcny of t':.le l,oil1ts ",'.'lch I 

have Flentior.eo to you -er-e today. Similarly, each IJoint 

an it i,let the del')artment's interest, ,',as covered l;i th 

otiler d epa.r t.non't a Lnc Lud i.ng the Governor's office. ActiVE) 

to a great degreee in t:lis effort t.as no~)ert l:c::ahon. 

So Has the NortheE'.stern "leed Control Conference, for 

tile ball 1'ihich 'ie carried lias tile one you fashioned. 

You made it; lie bough t it and put it in ;;1£1.:'. 

SOli1et~_mes ,;erind difEculty in movi.ng tllat ball. 

In cl1sc'Ussin(5 the mat t.en ';i tIl sone foll:s l:i th r;ut~ers, 

u e v er e told, liThe difficulty is the industry has 

gotten ~head of the text books; and the difficulty 

l:i th the te;~t boolta is that this uho Ls field is moving 

so quicldy ah sad that one ooes not 1:nol; vh er-e to 

beGin. II It is t:lis difficul ty whLch has contributed 

so much to the confusion of the press, radio, end 

telev1s~on. EVen so august a publication as the 

N'e"1 Yor]~ TE:ES adds to the confusion. 

For example, there recently ap:/enred in t:le TII:.ss 

an ar t Lcl.e on u e ed control chemic2.ls ~)y 2.D author vrho 

lias reaJly nixed up. Uhen one rnan called the TII,::B and 

l'.s'~€c1 to tr,l'.: to the au tho r , he lias told the article 

l;as by

He lau:j1ed to h1mself and loo!:ec' 12.t me ~j1 th 

the e:'e of e::;)e1'1ence. "You knot: \':hat 1s set1d in 

such ce.aea , don't you?,1.'! he as~:eCl.And then \';1t:1.out 

iiai tins for me to reply, he sa1d~ "Pro/3ress must vlai t 

for t~le death of the incumbents. 

He r~ay be r1(3h t. 1'1e nay have to iJa1 t 1n nany 

cases for theeventuill textbool:s, for the n eu grae 1s 

of a nevi era to come forth i';1t:l the neil era. 3ut 

I ho',e not. If l)roper, forthr13ht representation 

of this :)ro::-ram i'l1th £'.11 it im"11es 1s mc.Je, ti,len 

t~lEre i:ill follOi:an unoerstand1ng; an6 i';ith 

understc.nd1n,: liill surely come an ende aem snb , 

I svBt three years calling on the Pen~sylvan1a 

Turnc,i!:e. Finally, I met "lith r:ich2.el Balter, Jr., 

Consul t1n::; ]113111Eer., He had ref'1.1sed,- had 

thrm'il1 t~,1is prog1'am out of the b1. 1CLr;et i.uen 1t 

ap')eal"ed it i';ou1d 'be adopted. But after 20 minutes 

of prese~tationof many of the facts I have covered 

here today, and i;ith pictures ahow Lng the l'esults, 

::~,chael 32.!:er Jr., foremost hi,3'1\i£>.Yc onsg l, ting 

engineer in the United 3tates turned and said, 

"Certainly, such c. tool should have a place in every 

higlnigy l)l'ogram ." 

On AU[51.1st15 last, the TurnIli':e 1)ut 0uta 

special 1)ub'.1ci ty release tellinG t:le '~:otorist to 

tre.vel V,le pollen free Pennsylvania Turnp11:e. 

And t~lis year, 't\'iO cmmties in Neil Yorl: State 

as a res'.'lt of County L::t'I'; 22 L.A did their com1~lete 

roc.ds. In Broo!!Je County, over 1500 miles of roads 

u er e clEC'.red of rc.3~ieed

292. 

Broc::Je :;, Gr,:;rUGEI.coun t ;« s ";1 th si~nific2,bt 10\: coun t a 

:'.n :~e~: ::[01'1: Str,te :)1~ovide s:mm:~)lss of ·.:·~E:'.t can be 601'1e 

':1 tll C'. l)l~o:perly conduc t sd ragi'ieed control ,roc;ram. 

Actually, ,·;lHJ.t shou'ld ")6 00ne is c. l'2.3i:ec0 control 

"l'(J"r::'ID encompassing the I:etroroli tan Ns'.; York area. 

It c ov Ld 1)6 clone for t'l'10 million do l.Lar-s , It miGht 

")e ['. i:Orthi;hile pr-o jec t for one ofopr 3'oundatiol1s. 

If Er. :;oc':sfeJ.lel~ uer e fu l.ly 1nformed of t:le pr'ob'l em 

~m~ the fe.cts, he f11~ht 1Je pe r auo.d ed to present the 

project to t:le :':'ocl:efeller Foundation. 

T'is, hot. ever , 16 ano t.i er ua t t er , For the 

~)ur')ose:J of t",.'is neeting, let rue re:;ee.t, the mo s t 

im:Jort2.nt t'l.i:'G Ln a ragt-leed control proGram, 1n 

any ";sed control pro::;ram, is 1:moJ.1c relat1ons. 

I have encJe2.vore(~ to cover here 1';i t'1. you today aon e 

of the

lUCENTbEVEtO~' tN, PHRAGMITBS ComaOL 

by' 

293. 

~q~ H. Stee~s 

Bur~u of Sport ll'~beJ:ie. and Wf.lclllf. 

U. S. Fish arid Wildlife Service 

Laurel, Maryland . 

and 

Everett B. C~.rl.in ancl Robert,4."Beck 

Delaware, Board of Gale .nd 

Dover,aall'Del.".re City, Delaware ' 

F1&h C~as1oner. 

CODIIIIPn reed or phragmi tes

294. 

experimental treatments have, ~en made. Early studies showed that in 

dry sites dalapon at rates of 30 to 35 lb/A was effective in controlling 

phragmites. AlDitrol, applied at rates as low as 16 lb/A, also controlled 

this plant. These treatments were not very effective in wet 

sites, however. Subsequent studies with mixtures of dalapon and _trol 

showed promise. This paper summarizes results of recent tests with 

herbicides used alone and in combination. It also appraises the problems 

of aerial application. ' 

Field Study Procedure 

Most tests on phragmites were made on l/lOO-A and l/40-A units. 

Later, some treatments that showed promise were replicated by airplane 

treatments of one-acre strips. As response of phragmites to control 

was different in non-flooded sites than it was in flooded sites, a series 

of treatments was made in both types of habitat. 

Non-flooded Sites. In dry sites, dalapon was applied at rates of 10, 15 

and 20 lb/ A during d~fferent stages of plant growth. In like manner, 

2,2,3-',l'PA was tested in a smaller series of trials. AlDitro1 was applted 

at dosages of 2 and 4 lb/A. some treatments were made with monuron at 

6 lb/ A. Then mixtures of thesAherbicides were applied at the rates 

given above in a series of adjoining plots. In addition, tests were 

made with erbon at rates of 15 and 25/A, with neburon at 4,8, 16 and 

24 1b/A, with the sodium salt of 2,3-dichlorobobutyrate at 35 1b/A, 

and with simadn and three related formulations at 10 lb/A. The 

chemicals were applied at different stages of phragmites growth. 

Wet Sites. Because results from preliminary studtes indicated that 

treatments that were successfullil. non-flooded sites were not as 

effective in wet sites, a different series of tests was made in 

flooded habitat. In these later tests, treatments were limited to the 

flowering and early fruiting period when phragmites was known to be 

most vulnerable to control. Dalapon and 2,2,3-TPA were applied at 

rates of 25, 35 and 45 lb/A, emitrol at 2, 4 and 8 lb/A and IIIOnuron 

at 6 lb/A. Mixtures of these herbicides also were tested. Additional 

tests were made with dalapon an4amitrol at higher dosages. 

B.esu1ts 

Non-flooded Sites. Amitro1-dalapon mixtures yielded effective results 

in dry sites and were IIIOre econbmical to apply than was either herbicide 

used alone. For example, control was obtained with _itrol when it was 

applied at lS lb/ A, at an approxiiD4te cost of $60/ Ai control also was 

obtained with da1apon when it was applied at 30 lb/A, at an approximate 

cost of $30/A. However, we repeatedly obtained good control with 

mixtures of da1apon and _itr01 at respective rates of 10 and 2 Ib/A. 

the total cos t wa.8 approxlmately$18/ A. '!be period when treatment was

295, 

effec tive extended from the time the plants were 30 . inches in heigl;Lt to 

the time of early fruitiug. Attempts to obtain control by aerial 

applications were not successful, for the most part, because the required 

amount of herbicides was not applied. 

Other aspects of treatment with this mixture deserve attention. 

AlII1trol 18 translocated much more readily than 18 dalapon. In situ&tiollS 

where spray coverqe 18 irregular, a mixture of the two harbicides can 

result in a more uniform kill than results when dalapon 18 used alone. 

Evidence that translocation occurs readlly i8 shown by the phragmites 

kill in the buffer strips that separated the plots. Repeatedly..most 

plants in these strips of 15 to 20 feet in width have been controlled 

by these treatments. 

Amoug the other herbicides tested. erbon is of interest. When this 

chemical was applied at lowdoaale •• it appeared toeause a limited sol1 

sterilization. which d:l.sappeared in a short time. In earlier tests. we 

found that applications as low as 15 to 25 lb! A could control phragmites. 

Studies of treatments that were made at different times revealed that 

phragmites can be controlled at rates of 15 lb!A in non-flooded areas 

if the treatments were made 3 months,or more before the cessation of 

plant growth due to cool weather. Sterllant-t~e herbicides that have 

limitea residual effects can be of considerable value in controlling a 

non-dedrable plant without destroying the productivity. of the sol1. 

Another interestiug feature of "the low dosages of erbon was that there 

was some selectivity. For example. pokeweed (Phytolacca americana) and 

some other species were not kllled by the treatmeDt •. 

Of the other herbicides that were tested the sodium salt of 

2.3-dichloroisobutyrate yielded effective control at 35 lb!A but 

neburon •• 1mazin and related formulations were·not effective. The 

effectiveness of 2.2.3-TPA cannot be completely evaluated until the 

1959 growing season. . 

Wet Sites. In wet sites, we were unable to control phragmites with 

dalapon alone, even;w1,th applications of more than 100 .1b!A. We 

obtained sporadic contr9l with _trol duriug the vulnerable period 

of flowering and eafly fruitiug. Too much of e1ther dalapon or mitrol 

appeared to cause ~:faat contact kill of the leavea and stems that pre .. 

vented translocation. In the case of dalapon. this occurred at rates 

of about 70 lb! A, . but even at or below this dosage control was 

ineffect;ive~ Iil:,'the case of _trol. the amount that was required . 

to controi. the p11lf1.t.was close to the level that' prevented translocation 

of herbic1d1i!. ~~n fDitrol was applied at the rate of 24 lb! A. resul.ts 

were erratic. C~lete control resulted from amitrol treatmen.ts of 

20 lb! A. Similar difficulties were encounterecl when mixtures were used 

at higher dosages. Uniformly good control resulted from applying .. 

mixture of dalapan at 25 to 30 lb/A with amltrol at 4 to 5 lb!A. In 

treatments by airplane, control was rated as 90% and sometimes 807.. 

Under these circumstances it would be advantageous to make clean-up 

treatments the following year.

296. 

Control was only partly effective when dalapou-lIlOlWron mixtures· 

were IIsed. 

When we compared these results with treatments made in other 

sections of the country. we found that Dill (1958) controlled p~agm1tes 

in wet sites in Minnesota by applying amitrol at a rate as low as 8 lb/A. 

APpareDtly. where the growiDi SeasOD is shorter .lUld.,the plant exhibits 

a 1... vigoroua type of growth, phragm1.tes can bec.ontrolled lIlOre r8&dl1y. 

Likewise, we aoticed that effective results were obtained with lesser 

amoUllts of herbicide in New York City than were required in Delaware. 

'!'hese variations were to be expected. For this reason, it of teD would 

be advantageous to. make a series of pilot tests in probl_areas to 

determine the lIlOSt practical rate of application. . 

b:,obl_ 

of Application 

Ground Eguill!!Dt. In dry sites, power..spray equipment was operated 

from a truck. However, it is d~fficult to llIOVegrouacl equipment over. 

rough terrain through this high jungl ... type grass. In flooded are .. " 

it is often impossible to ~ke lIIOl'e than marginal treablent from floatiDi 

equipment. 

Aerial Equipment. In many ..... , an airplane is the only 1I!881l8by which 

a herbicide can be. applied. Application by plaue, however, presents 

many difficulties and pitfalls. 

. . 

One of the first problems we encountered was the relU(:tanceof 

commercial operators to allow their equipment to be used for herbicidal 

work. '!bey were afraid of contem1natlon that would damage agricultural.: 

fields when the plane was used later for crop treatmeDt. 

Equipment must be free of leaks. No airponoperator would be 

happy to bave the grass on his parking ereaaDd runways subjected to 

spot application of the chemicals used in this. :work•. This would be true 

also if a CODYenient field, rather than an airport, "as used as a bese 

of operations. Probably even lIOre important is the fact that it is 

nearly impoa8ible to load lUld deliver these chelllicals without PaseiDi 

over agricultural land. As. many of the areas to be sprayed areedjacent 

to croplaod, equipment IllU8t DOt only be free of ,~eaka but also must beve 

positive and complete cutoff at the nozzles 80 that no chemicals escape 

when turDS have to be made over growing crops. If.,.C.lltoffs are made at 

the tank, extreme care should be taken not to fly 9Ver cropland. 

Anotbel' problem coneeru the dosage that is applied. Beceuse of 

the difficult1es of cali~rat1Dg .praying equipment, it is necessary to 

see if the actual rate of application i. the ... as that which t:iua 

equipment is set to deli"er.~ .For ~le" a spra,.. that supposedly 

del1ver. S007galloDS per aCre'm&, actually put ou~ 4.01' 8 galloDS.per . 

acre. In experimental wor:k, it 1& importallt to know the exact gallonaae

297. 

that is delivered in order to be sure that the right poundage of chemical 

is applied. For control of pbrapites. a specific poundage of herbicide 

is required. irrespective of the amount of carrier used. 

It is desirable for spraying equipment to be adjustable for different 

rates of application. This is especially important in experimental work 

because the various formulations and combinations of chemicals IIIWI t be 

tested at different rates in order to determine the 1IIOateffective and 

economical treatment. It is also advantageous to have an accurate and 

a fairly wide range of adjus tIlIent8. from about 3 gall A to at leas t 

10 gallA. 

OUr experience with commercial aerial operators indicates that 

some of them are not very critical of the rate of application. It 

therefore is of the utmost 1lIlportance that the dosage be accurately 

determined. not only for the lake of economy but also in order to plan 

the treatlllent 10 that a variation of a gallon per acre either above or 

below the recommended figure will not seriously affect the results. It 

sometimes may be advantageous to racommend slightly higher dosages than 

those that are found to be effective in experimental tests. 

Precipitation and wind are the lIIOSt important weather factors to 

be considered in making applications of herbicides. Spraying should be 

done when no rain is expected for at least %de,y after treatment. Treat~ 

ment also should be made uDder as nearly a nO*w1nd condition as possible. 

This \18\1411y,wUl limit working time to a period of 2~3 hours immediately 

after daylight and to approximately the same amount of time in the 

eveDing just before it geta too dark to fly. Once a formulation and rate 

of appliCation hfve been established. a slight 8IIOunt of wind can be 

tolerated. because an experienced pilot can compensate for moderate 

drift if the area to be treated is large and if there is no agricultural 

land immediately adjacent. 

TO achieve ma~~ economy in eerial application. herbicidal 

treatment lhould be completed in a dngle fUght. The loading site 

should be as close as possible to the area to be treated, and the 

chemicals sbould be weighed and mixed ahead of time so that ground time 

ia kept to aD absolute miDimumafter the aircraft starts working. 

Ackno!ledpents 

The following chemical companies have been actively interested in 

these investigations and have furnished materials for testing. Amchem, 

American Cyan_d, Dow, Du Pont. and Geigy. J. B. Whel~ and 

O. Plorschutz, Jr.., student &Bsistants. U. s, fish and Wildlife Service. 

participated in the field studies.

298. 

SUllllllarY 

Tests of chElD1cal methods for control of pbragmltes were made in 

Delaware marshes in the summers of 1955-58. These investigations on 

control of pbragm1tes revealed that a IIlixture of dalapOll aDd amitro1 

was superior to either herbicide used done. Most effective and least 

expensive cOlltrol on dry sites.wu obtained from·an applicatiOll of 

mixtures of dalapOll at 10 1b/A with &mitrol at 2 Ibl A. Uniformly good 

control on wet sites resulted from a mixture of delapon at 25-30 lb/A 

with amitro1 at 4-5 lb/A which was applied duriug the floweriug aDd early 

fruitiug period. Effective control of phragmltes with lesser amounts of 

herbicide is possible .inother locations where the growth of this grass 

is less vigorous. . 

In many areas, aerial application of herbicide is the only way in 

which phragmites can be controlled. Requirements for airplane application 

are avoidance of damage to nearby croplands and correct calibration 

of equipment. To be economical, treatments should be completed :Ln a 

single flight. 

References 

C:Lted 

Beck, R. A. 1957. Use of herbicides to increase game foods aDd edge 

in solid stands of phragmites. Proc. Northeast 

Wildlife Conference. 

Dill, H. H. 1958. Controlling cattails aDd phragmitn with am1trol. 

Paper to be presented at NCWCC. 

Martin, A. C., R. C. Erickson, aDd J. B. Steenis. 1957. Improvement of 

duck marshes by weed control. U. S. F:Lsh and Wildlife 

Service, Cir. 19 revised, pp. 35-38. 

Steenis, J. H. 1955. Weed control in marshes. Proc. NEWCC,pp. 513-517. 

Steenis, J. H., H. P. Cofer and R. A. Beck. 1951. Experiments to 

improve the :thousand-,A.cre Harsh, Delaware City, 

Delaware. Proc.Northeas t Wildlife Conference. 

Steenis, J. H. 19S6. Progress report on phragmites control. Abstracts WSA. 

SteeDis, J. H. ~ C. C. Webster aDd R. A. Beck. 1954. Progress report on 

studie. ·on the control of pbragmites. U. S. Fish 

and Wildlife Service, mimeo raport. 

Steenis, J. H., N. G. W:l.lder, H. P. Cofer and R. A. Beck. 1954. The 

marshes of Delaware, their improvement and preservation. 

Delaware Board of Gameand Fish Comm., P. R. Pub. 

No.2, pp. 33.

299. 

Ca-lPARATIVETESTS CF VARIOUSHEJmICIDESONWATJmCHESTNUT 1 

JohnH. 

Steenis, 

NewYork Sta\e Censervat10n Department, 

A.l'baIIY. N. y ~ 

and 

Bureau of Sport Fisheries and Wildlife, 

U. S. Fish and Wlldl1fe Service, Laurel, 

lti. 

INTRODUCTION 

Waterchestnut (Trapa natans) was introduced into New York 

about 1884 and is now esmed in some areas of Massachusetts, 

Maryland, Virginia and Vemont. It seriously interf'eres 

With fishing, waterfowl hunting, boating, sw1JmI1ngand other 

use of waters by fonning 1mpenetrable mats of vegetation during 

the sUlllller and early fall. The plant is an annual and decays 

after frost leaving an abundant crop of its large, thorny seeds. 

Many of these sprout the next spring, but there is also sane 

delayed germination over a period of several years. Canplete 

eradication has been achieved in a number of areas by destroying 

the plants prior to seed production for several successive 

years, The methods generally used in oontrol programs have 

been spraying with 2,4-D or underwater outting of heavy infestations 

and handpulling of light infestations. Control projeots 

are ourrently in operation in New York, Vennont and Maryland. 

Details on earlier oontrol work in New York including tests 

of methods are given by Smith 2 • In recent years, beginning in 

1955, an eradication project has been operated With the aid of 

• 

lfAcknOwiectgments. This study could not have been made without 

'the active interest and assistance of several. chemical companies 

who provided materials for tests: Amohem, Dow, General, Chipman, 

Rohm & Haas and DuPont. J. H. Gallagher of Amchemactively 

participated in field work as did ·R•. H. Smith, New York State 

Conservation Department; J. B. Whelan, U.S. Fish and Wildlife 

Service; W. R. Miller, Vennont Fish and Game Service; and G. F. 

Beaven, Maryland Department of Research and Education. 

~/Smith. Ralph H. ExperiJnen~l Control of Water Chestnut (Trapa 

natans) in New York State, New York Fish and Game Journal 

~9J. 1955.

':",. 

300. 

Dingell-Johnson funds and has !iestzyyed or reduced many 

infestations which threatened to spread into new areas. The 

large infestations of the lower Mohawkand Hudson Rivers, 

however, al1lOunting to several. thousands of ,acres, have presented 

a l1IOreditficultpJ'(lQ;Lem.Tne develQPIll6nt of improved, 

low-cost methods might be expected to 'increase' the chances of 

successfully eradicating these large infestations. There has 

been an increasing number of'··requests by property owners. and 

others for inforlll!l:tion onllll'lthods forcombattihg waterchestnut. 

and it is expected that the development of 1mproved methods 

would result in considerable control work by individuals ae 

well as by state agencies •. 

;~'::rn planning the pres,ent.tests, pUblished arxl unpublished 

inforiJlat.ionfrom several sources was avaUab1e. Published 

work by Smith has alreacly been. ment.ioned. Further testing on 

afield basis was done in the New Yorkoontrol project during 

1956 and 1957. In 1956 and 1957, tests were made in Marylar.d 

;, by Steenis. 

Any successfulmethod'!oreradication of 'waterchestnut .must 

-.stop seed formation. To be practical for large-scale application 

it should be rapid, economical and safe with reference to 

personnel, to adjoining property and to other uaee of water.· 

Although a number of. methods currently used. in control projects 

meet these requirements reasonably well for certain situations, 

the testing of new and better methods is consi4ered desirable. 

It should be emphasized that a number of the tests made were of 

a preliminary nature, and it is not possible at this time to 

include a full comparison of relative effectiveness or costs on 

a field application basis. . 

. NmolYORK19.58 SPRAY 

The spray method used by the control project of the NewYork 

State Conservation Department during 1958 arfordsa Ilseful basis 

for comparing other naterialsor methods of application and wUl 

be discussed first. This emulsion spray was fo:rmuJ.at.ed as .follows: 

2/3 gallon 2,4-D (1lI1Xture ·of isopropanol anddi-isopropanol amine 

at 4 1bs. acid equiva1entper ga110n),2 gallons kerosene, 1 pint 

Igepal CQ-530 emulsifier (Antara Chemical. Company) and 20 gallons 

water. This ~tals slightly over 22-2/3 gallons, but water 

was not measured with exact precision in field use and, bence, 

the spray tank load could be considered to be about 23 gallons. 

The procedure followed· in' mixing was to put in about 10 gallons 

of wat.6r, to add>the 2,4-1) and the 1gepal dissolved in kerosene, 

and then to pour in the other 10 gallons of water e , This gave 

a good emulsion.

301. 

Spraying was from a specially bull t 18-foot alum1num boom 

having 1) jets, mounted on 12-foot slum1num boat powered by a 

4 horsepower air-propeller driven outboard motor. The speed 

was estimated at )-1/2 miles per hour. The apertures used in 

most of the spraying were T jet No. 8004. As a hose spray had 

been used before the spray boom was devised, the pump was of a 

high-pressure type with a gauge which was not accurate for 

exact reading at low preseure , It was estimated, however, that 

pressure was about )0 P.s.i. When allowance is made for factors 

such as over-lap in spraying and variability in speed, the 

rate of application was estimated at about 4 pounds per acre. 

In most waters where the emulsion spray was used effectively 

in 1958, it is concluded that both surface and submerged effects 

were involved. It was particularly evident that "spot spraying" 

of scattered plants was not so effective as treatment of entire 

areas of dense growth even though the spray boom wet the leaves 

equally well under both conditions. In spot spraying, the underwater 

effect of the spray would be quickly dissipated by diffusion 

into adjacent untreated waters, whereas in treating larger 

areas more effective concentrations of 2,4-D are maintained. 

However, a weakendng of the submerged effect by diffusion in 

deep water occurs and would explain the sprouting of weak, 

lateral rosettes which was found to occur repeatedly. In some 

areas one application, properly timed to prevent such lateral 

rosettes from setting seed, gave successful control. Although 

early spray applications (mid-June) were successful in greatly 

decreasang the seed crop, a second spraying to destroy lateral 

rosettes late in the season would. be necessary for complete 

suppression of seed. 

SMALL PLar 

TESTS 

Two areas of the MohawkRiver where· waterchestnut growth 

was dense and where there was little chance of interl'erence with 

observations over a long period were selected for test plots of 

1/100-acre size (21 x 21 feet). These were at Allen's Cove 

near Crescent, and Wagar I s Cove near Vischers Ferry. Numbered 

stakes were used to mark the plots. A number of chemicals were 

tested, most of them at several rates of application expressed 

as pounds of active ingredient or of acid equivalent per acre. 

The materials used fall into three groups: (1) granular formulations, 

(2) sprays of solutions or of emulsions, and ()) invert 

emulsion sprays (herbicide disoolved in water and enclosed 

in oil droplets). 

The plots were. laid out with intervening buffer zones left 

untreated. Earlier plots were laid out with 6-foot buffers and 

later ones with 2l-foot buffers. Although the materials were

302. 

carefully sprayed or scattered in each test plot, there was 

in some instances interference with interpretations because 

of subsequent diffusion. Larger buffer areas would have been 

desirable. 

During 1958 tests were made on 71 plots in New York, 12 

in Vemont and 3 in M9.ryland. 

2,4-D 

GRANULARFORMULATIONS 

A single plot at the 40 lb./A. rate was treated in New York 

on June 17 when young rosettes were at the surface. Control 

was excellent. An area at least four t1lTles as large as the plot 

was clear at the first check on July 15 and remained clear. 

Monuron-TCA (General Urox Weed Killer), 2'2$ on granular 

mineral base. Plots at 10, 20 and 40 ssrtx: rates were treated 

on June 17 in NewYork. There was no control at the first 

check on July 17. Thereafter, diffusion· from nearby applications 

of 2,4-D and 2,4,5-T on vermiculite made it impossible 

to differentiate between the treatments. A delayed effect 

might have been responsible for some of the later, good control 

in the Urox plots. 

Monuron, 251>on pellets. Plots at 10, 20 and 40 lb./A. 

rates were treated JUne 17 in NewYork with no control. 

Silvex, 101>on 8-15 rr.esh attaclay. Plots at 2, 4, 8, 12, 

16 ana 20 ib:"'(l:. rates were treated on May 22 and at a 40 

vs.]«, rate on June 17 in New York. There was only a slight 

reduction in density of plants at the 20 and. 40 lb./A. rates. 

CBlJIM(Chipman Chlorea) in granular form. Plots at 50, 100 

and 150 lb./A. rates were treated on June 17 in NewYork with

303. 

no effect. 

25% em 

s were 

SPRAYSIN WATER,KEROSENE-EMULSION OR KEROSENE 

2,4-D amine salt, kerosene, and 

(New or ormu ion as previous escri excep a greater 

dilution of water was used). Plots were treated on July 15 

altCichecked on September 12. llist rosettec 'Were killed or 

offeetive:lJ' stunted, but a few seeds of possibJ.e viability 

were still att.ached. Weak lateral rosettes were observed. 

Results were best in the 8 lb./A. plot and slight:lJr poorer 

in the 4 and 2 lb. / A. plots. 

2 4-D butoxyethanol ester in water. Plots were treated 

on JUiY 13. \\'hen cheeked on Sept:eillber 12, rosettes were 

most:lJ' killed or disintegrating, but some seeds of possible 

Viability were still attached. These plots 'Were in a zone 

of diffusion from the plots \reated with 2,4-D and 2,4.5-T 

on -"ermicuJ.i te and could not be evaluated precise:lJ'. The 

8 Ib./A. plot had a few seeds, but the 4 lb. and 2 lb./A. 

plots nearer the plots of 2.4-D and 2,4,5-T on vermicuJ.ite 

'Were clear of plants. Applications made in Maryland on 

June 4, 1956 at 4 and 8 lb./A. rates gave complete control 

at the higher rate and nearly equal control at the lower rate. 

A preliminary trial at a 4 lb./A. rate in which triethanalomine 

was added to 10 ratio gave complete control. 

2,4-D but~etnanol ester in kerosene. Applications were 

made on JUlY ana checked on September 12. Most rosettes 

were killed or very 'Weak, but some seeds of possible viability 

were still attached. The 8 lb./A. rate was much better than 

the 4 xe.!«. rate which, in turn, was much better thaD the 

2 xe.!«, rate. 

MCPAin uater. Applications were made on July 15 and checked 

on SeptE;lllber 12. Many plants had disintegrated, but some seeds 

of possible viability 'Were attached and some rosette" 'Were recoverillll:. 

The 8 Th.JA. rate was de;t.:initely best with the 41b./A.

304. 

Dalapon(soluble ~\oldar). An application ata rate of' 

6 lb./A. was made on U1Y 16 and checked on September 12; . 

This treatment was inet'£ect1ve •. 

Amitrol (soluble powder and li~id). Applications were . 

made at a rate of 2 ib/A. on JUlY and checked on September 

12. These treatments were ineft'ective. 

TCA (wettable i61er). Applications ata rate of 5 lb./A. 

were made on JUlY ana checked on September 12. These treat,;. 

ments Were inet'fective although rosettes showed some damage. 

INVERTEMULSIONSPRAYS 

Invert 2.,4-D bu~ethano1 ester. (Amchem). Applications 

were made on Jiiiy i~Treatiiients at rates or 1, 2, 4 and 8 

lb./A. resulted in partial control. Most of the rosettes 

were kill~ but sane were recovering and some seeds of possible 

viability were still attached on September 12. . 

DISCUSSIONANDCONCLUSIONS 

In evaluating results and drawing conclusions it is importantto 

bear in mitxl. that the trials on a small plOt basis 

were for the most part exploratory and that clOse standar

When all field data are considered together, it seems clear 

that any surface treatment of onlY the rosettes of water chestnut 

does not reach the entire plant. Some of the sprays do, 

however, penetrate under water to. a material extent. Absorption 

from pellets at lower parts of a plant is considered 

likelY to result in upward translocation of the herbicide and 

this would explain the complete kill. Vermiculite, which 

graduallY sinks, affects both top and underwater parts of the 

plant and gives a canplete kill. Improvement in surface sprays 

might be expected through changes in specific gravity 

to provide a slow sinking material. One test in this 

direction involvin£ the addition of triethanolamine 

into adjoining untreated areas of water is not possible. 

With limitations of the above memtioned types in mind 

W~ can summarize conclusions: 

(1) Of all the chemicals tested, 2,4-D gave the best 

r~sults. Although some formulations also contained 2,4.5-T, 

this compound has not shown any advantages over 2,4-D on 

the basis of previous study. 

(2) OnlY 2,4-D in formulations of attacliy and V(;rmiculite 

granules gave a complete kill characterized by no 

regrowth. However, earlY treatment with a relativ~ly insoluble 

formulation of 2,4-D on attaclay failed to give 

control even though it might have been expected to remain 

active for a long period. On the basis of the one later 

application in June at a heavy rate (40 1b./A.) it is clear 

that 2,4-D pellet treatments have good possibilities. Vermiculite 

impregnated with soluble 2.4-D was tried only in 

July on dense stands but gave excellent results. 

These results with vermiculite containing a soluble form 

of 2,4-D (amine salt) suggest that perhaps attaclay pellets 

impregnated with more soluble or emulsifiable forms than those 

tested constitute a promising field for further experimentation. 

(3) Conventional sprays of 2,4-D in water, kerosenewater 

emulsion or kerosene gave effective results although 

generallY did not stop all regrowth. The sprouting of lateral 

rosettes is an important factor to be considered, but proper 

timing of sprays can avoid any setting of seed by these before 

killing of the plants by frost. 

(4) Invert emulsion spr

)06. 

A PJl>GRF'SS~".:P()t1T 

ON SIMAZINEl'Y)t> AQUATICVfE~DS 

By 

Edwin O. Sohnoidor (1 

Simuzinc (2-ohloro-4,6-bll( ethylamino )-s-triuzin" was 

introduood oxperimentally to oxperiment station end other 

'~rker. in 195.. Outstanding pertormnneo as a pro-emergenoe 

wvod oontrol ohamioal WQS reported in oorn (IDd in s

307. 

expcrimont station workers on mnny spooies of ornnmentals nnd 

forest oonifers huve found no injury at tho suggested rates 

nnd only minor symptoms when rates were inoreased several times 

in near ly pure sand oul ture in pets in tho groenhouse. 

It has boon determined that oern is ablo' to deoompose 

SimHzino within the plant probably by enzyme notion shortly 

flfter being taken from the soil by the roots. While on the 

othJr hand, susoeptible plants either oannot deoompose the 

absorbed ohemioal,or do so at a rate so Slow that death of 

the plen t 000 ur s bof'or-e decompos i tion. 

Apparently rootod aquatio wGeds take the Simazine up 

through the roots whereas the unattaohed aquatios have the 

ability to piok up the ohemioal from the water. 

MODEOF ACTION 

Experiments have demonstrated that Simazine is taken up 

by tho roots of plants and translooated upwnrds to the leaves. 

Seods in treatGd soil germinate normally and the seedling is 

killed nt, or soon after, emorgenoe. Rooted aquatios apparontly 

absorb the ohemioal from th'3 soil. 

Tho first plant symptoms eppec r us ohlorosis at the lonf 

tip and margins. Tho symptoms oontinue to progress r~d neorosis 

follows. Th.) indiodions are the ohemioal int·orferes with the 

Hill reaotion or tho ability of the ohloroplasts to break down 

water to hydrogen and oxygen in the presenoe of light and iron. 

The chend on I 'lppwontly does not penotrate the unbroken outicle 

of the leaf. but must enter through the root. 

The mode of aotion in algae hns not been determined but 

it is thought to be by absorption. The solubility of Simuzino 

in water oan bo in oxoess of tho lethal oonoontration found to 

be effeotive on algne. 

PERFOPJ.ffiNCE 

Simnzine has b oon evnlunted by experim'mt station workors, 

state fish biologists and others for toxioity to fish and for 

the herbioidal porformanoe on rooted and froo flonting o.qur..tios. 

1:ll1kor (2) worked in smnll enolosuros in n pond made by using 

two stakes at tha euter edge of tho plot, and. sus pendf ng rt he 

pkstio shJot from styrofoo.m floats. In thuse onolosures 0. 

single ep ccd es , or sevoral spooios of woods oould be tro~tod with 

'1 ohumioal at vr,rying rntos and in tho presence of fish and fish 

food organisms. Rates us ed wore up to soil sterilizution

308. 

ooncont rttd ons or 10 lbs. por !:ore. Th

aN pondwccd (P?'tu~~otO!:,!!P..£')' muskgrass (~);'Milfoil 

(~~rioPh~llum speoatum-r, fanwort (Cubombu ~u2:01ininna), horned 

pond wee (Zannniohellia palustris), und numerous speoios of 

filumontOtls: algaa. Theohomioc: itlns been founii' tobo most 

offvotiv'lin o Io sad nrOQS with n minimum run-off nnd whon .tho 

entire aran is trunted ~t ono timo. Thowettnble powder appears 

most offootivo on nl~Qe, wheroas tho grunulnr'matorial gave 

tho bost

*P1eroe, Proo. 12th Annual Meet. Northeast. Weed Control cant. 

Jan. 1958. NewYork 

310. 

Further study of the Effeot of the Weedioide Kuron upon the Flora 

and Fauna of Long Pond, Dutohess County, NewYork. 

Madelene E. Pieroe, Vassar College, Poughkeepsie, N. Y. 

The purpose of this paper was to repeat on a larger soale 

the pilot experiment oarried out on Long Pond in the gummer of 

1957.* An attempt was made to determine the effeot of KY!:.Qnupon 

the plankton and benthio organisms, as well as upon the weeds, 

when a limited area of a pond is sprayed. The dates during whioh 

the study was made were June 11 - September 26, 1958. 

I 'Irish to thank Mr. John Gould of the NewYork State Department 

of Conservation for his oontinued enoouragement and help. 

Thanks are due also to Mr. John Grimm of Rhinebeok, NewYork, who 

gave a day of his servioe to spray the area professionally. To 

Mr. otto Johnson, I am indebted for oonstant use of his shore 

line as my base of aotivity, and his boat for sampling. DoW 

Chemioal Company prOVided the ~ and Vassar College gave a 

small grant to defray oash expenses inourred. 

Long Pond, previously desoribed in detail (Pieroe, 1958) is 

a very shallow pond, 1 - 6 feet in depth, with a broad border of 

aquatio weeds. These inolude submerged, floating, and emergent 

types. Even the so-oalled channel, 5-6 feet in depth, has a dense 

carpet of submerged weeds Which are mostly Potamogetons. 

Two aores of the pond were staked out on June 10, 1958. This 

area was located off shore, included the ohannel, but did not inclUde 

any part of last summer's experimental plots. The depth 

varied from 1-2 feet along the shoreward boundary, up to 6 feet 

along the inner boundary and also in the northeast corner of the 

area. 

On June 11, the first sampling was done. This set the pattern 

for the following ones whioh were oarried out on June 21, immediately 

after the spraying, July 7, July 25, and Sept. 20. Since 

the experimental plot was 400 feet in length, stakes were placed 

at 100 foot intervals. TwOsampling stations were selected at 

the 100, 200, and 300 foot intervals. One station was designated 

as the west station, the other as the east. The same simple 

routine of study was used as in the previous summer. At eaOh 

station the bottom temperature was recorded, a water sample from 

the bottom was obtained, and two dredges for benthio forms were 

made With an Eokman dredge. One plankton haul for the entire 

area was standardized as much as possible by rOWing on the same 

route for the same duration of time. In the field the contents 

of the dredgings were sieved, identified, and counted. In the 

laboratoI'1, the plankton was studied and identified and the determinations 

of pH and 02 in ppm were made by use of the Hell1ge

311. 

Testing 

Apparatus. 

The control area was selected at a point south of the treated' 

area, and far enough removed to be unaffected by diffusion of the 

~. 

The applioation of Kuron was made by a professional on June 

20. The Kuron was sprayed from four jets at the stern of a boat. 

The concen:t"'rition used was 2 ppm in the pond. 

Before the spraying a careful map of the pond weeds was made. 

The speoies found were the same as the previous summer (Pierce, 

195B). Near the shore the commonsubmerged plants were Utricularia, 

Chara, and Potamogeton amplifolius; Nymphaea odorata was the common 

floating type. In the deeper areas, the oommonsubmerged plants 

were 1:. amplifolius, 1:. crispus and 1:. natans; the oommonfloating 

types were Nymphaea odorata and Nuphar advena. 

The most speotacular and immediate result s of the treatment 

by ~ were observed on Nymphaea, the white water lily. Within 

24 hours, the leaves showed the typical brown spots, the stems 

were lengthening and beginning to curl. After 3 days, the typioal 

reaction was eVident; the stems were inoreased in length by several 

inches; many were coiling like corkscrews; some were arching above 

the surface,. and as a result many leaves Were overturned. The 

tangled red stema and red undersurfaoe of leaves gave a rosy hue 

to the entire area. This effect of accelerated growth became 

even more notioeable up to the 7th orBth day. After about 2 

weeks, the broken blossoms and leaves presented a tangled, unpleasant 

mass of dead. and dying plants, which gradually decomposed, 

dropped to the bottom, or were removed by the wind. By 4 

'lTeeks, on July 20,the 2-aOl'e plot stood out distinctly as a surfaoe 

clear of lily pads, when contrasted With the surrounding 

water of the pond. Probably this condition could be hastened by 

mechanical removal, such as raking or dragging, of the dead weeds. 

For the rest of the summer and fall the surfaoe remained olear 

with minor exceptions. In early September, a few small red shoots, 

new growth of the white water lily, appeared, but these were practically 

negligible. In the deeper portion, several patches of 

P. natans appeared, but again these were rel'atively few in number 

and small in size. 

In summary it oan be said that ~ at a concentration of 

2 ppm was suooessful in olearing the surfaoe of forms such as 

Nymphaea, Nuphar, Brasenia and Pontederia. The oontrol area 

presented throughout the season a uniform lush green growth dotted 

with hundreds of blossoms. . 

The effeot of ~ upon the submerged plants was not as spectacular. 

It was much more difficult to observe, to interpret, and 

to evaluate the conditions even With the help of the map. Certainly 

no ~~~ent~ oan b~ made within a few days or even a week. After a

312. 

Chara and P. amplifolius were very much reduced; and later in the 

Siiiiiiii'e~, two-of the weeds utrioularia and!:. amplifolius were, for 

all praotioal purposes, cleared out oompletely, leaving a bare 

substrate. Chara was never oompletelY oleared out, but was much 

reduoed. When compared with the control area, which contained a 

"dense forest" of submerged plants, the nearly bare substrate of 

the treated area was marked indeed. 

The effeot of ~ upon the submerged plants in the deeper 

area'ir was not .ao suooessful. After a month, the thick carpet of 

potamogetons did not appear to be deoreased. Even by September 

these weeds appeared to mainta1n their abun&Lntnumbers. Comparison 

with the oontrol area showed little differenoe or oontrast. 

It is 'suggested that perhaps a higher oonoentration of ~ might 

prove more effeotive in these partiaularly dense areas of growth. 

The summer of 1958 was relatively 0001 and rainy as compared 

to the exoeedingly hot, dry summer of 1957 • During the period of 

June n-September 23, the bottom temperatures "Varied only from 

67 - 78oF., The pH remained, as before, remarkably oonstant, 7.2 

7.4.' The dissolved oxygen oontent also varied little, ranging 

from 6.5 - 7.5 ppm. Neither the pH or dissolved oxygen oontent 

showed any ohange immediately after the applioation of Kuron. 

Any variations in the oonditions were oomparable to the oontrol . 

area. 

The benthio organisms identified in 1958 oomprised the same 

large groups as those found in 1957; Anneli&L, Mollusoa, Crustaoea, 

and Inseota. The indiVidual speoie s were also the same. . At no 

time in the treated area did anyone group drOp out or show asignifioant 

deorease in numbers of individuals which was different 

from the pattern of the oontrol area. 

Exaot counts were not made on the largeaquatio vertebrates 

such as fish, frogs, and turtles. However, all three groups were 

abundant in both treated and ,oontrol areas throughout the season. 

Adult pickerel, perch, and sunfish were oftensaen as well as 

myriads of young fish. It is obvious that the Kuron had noharmf'ul 

effeot upon the vertebrates. In faot, the looal residents never 

reoounted a story of hundreds of dead fish along the shore, and 

even admitted the fishing was at least as good as usual. 

The plankton identified in the 1958 season was similar to 

that of the previous summer. (Pieroe, 1958) This proved to be the 

only group of organisms which did suffer at least a temporary 

harmful effect from the Kuron.. On the first day after spraying 

there appeared to be a deorease in abundance of the haul, and 

many dead organisms were present. Of the older forms, many ware 

abnormal in shape and the population as a whole looked II siokl/ • 

However, there were still living a fair numberot small, young 

orustaoean forms. A seoond sample was taken after 7 days, and 

still a third after 11 &Lys. On the seventh C1ayafter' spraying, 

the general picture was one of improvement. Within the Crustacea

313. 

there was a thriving population of tiny individuals. By the 

eleventh day, the general pioture was nearly normal, so that one 

might resonably say that within a two week period the plankton 

population would have returned to its original health and abun~ 

ance. One month later, when the routine sampling tor the pond 

was carried out, no difference between treated and oontrol area 

was observed. 

Mention should be made of a plot treated in 1957 with Kuron 

at a concentration of 1.3 ppm. The effect of the Kuron for that 

season has already been reported (Pierce, 1958). In the spring 

of 1958, when compared to its control, there was a definite decrease 

in the number of lily pads upon the surfaoe. However, it 

was obvious that although the surface had been entirely oleared of 

lily pads in 1957, in 1958 a substantial number were appearing. 

In fact by June 20, the numbers had inoreased so that there was 

little differenoe between experimental and oontrol areas. As a 

favor to the landowners, an unmeasured but heavy dose of ~ 

was applied, with the expeoted results of complete olearanoe 

within a month. It will be interesting to note the oonditions of 

this area in the Spring ot 1959. 

Summary 

1. Long Pond, a dhallow pond, is rapidly filling in with a dense 

population of emergent, floating, and submerged aquatio weeds. 

2. An experimental area of two aores was seleoted in June 1958 

for study during the seaso~ June 11 - September 26, 1958. This 

area did not inolude plots whioh were treated in the summer of 

1957. 

3. Preliminary study of the following oonditions was made on 

June 11: temperature, pH, dissolved oxygen oontent, plankton, 

benthio organisms, large aquatic vertebrates, and aCluatio plants. 

This routine study was repeated at intervals on June 21, July 7, 

July 25, and September 20. 

4. The experimental area was sprayed onoe With Kuron on June 20. 

The concentration used was 2 ppm. --- 

5. The effeot of the Kuron upon the Nymphaea was to acoelerate the 

growth within a few days, the stems and leaves then broke off, deoomposed, 

and the surface of the treated area was entirely cleared 

of lily pads in a few weeks. Pontederia and Nuphar also suocumbed 

to treatment but were slower in reaoting. The treated area remained 

clear for the season. 

6. The submerged weeds of shallow areas, such as, Utrioularia, 

~, and Potamogeton amplifolius were definitely decreased after 

one month, and in some areas completely eradicated. In the deeper 

area, where several species of potamogeton were extremely dense, 

little if any decrease in abundance was observed. 

7. In September, 10 weeks after spraying, a few new shoots of 

Nymphaea appeared in shallow areas, and several patches of P. 

natans appeared in deeper areas.

8. The temperature of the bottom water varied between 67-78 0F. 

9. The pH varied only 7.2-7.4. 

10. The dissolved oxygen content varied on:LYfrom 6.5 - '7.5 ppm. 

11. Plankton was oOhtin~ouslY represented by t~e same forms as in 

the preceding summer. For a week after spraying the population 

appearedreduoed in numbers, and individuals looked abnormal, but 

by the end of the seoond.week the popUlation exhibited a normli.l 

condition. .. 

12. Benthic forms were oontinuously represented by the same groups 

as in the preoeding summer. Their numbers and Vigor were not effeoted 

by Kuron, but paralleled the conditions in the oontrol area. 

13. Large aquatio vertebrates,. like fish, frogs and turtles maintained 

numbers and Vigor similar to the oontrol area. . 

14. Exoept for a temporary setback to some plankters, ~ applied 

in the oonoentration of 2 ppm appears to have no harmful effeot 

upon the fauna of this pond. . 

15. The experimental plot, completely cleared of lily pads of 

Nymphaea in the summer of 1957, showed in 1958 a growth nearly 

equal to that of the control. 

-

FIELD TESTINGOF KURONAS ANAQUATICHERBICIDE 

IN MASSACHUSETTS 

315. 

Introduction 

Mario M. Boschetti 

Sanitary Biologist 

Massachusetts Department of Public Health 

~ 

Under a special study authorized by the Massachusetts 

Legislature, the Departments of Public Health, Natural Resources, 

and Public Works have been conducting a research study on the 

chemical control of nuisance aquatic vegetation in Massachusetts. 

The study has been in progress since 1953. The field testing 

of Kuron was initiated in 1957, and the da~ in this paper will 

include results obtained during the period extending from June, 

1957 to November, 1958. A major portion of the Kuron used during 

this research was received gratis from the DowChemical Company. 

The author wishes to extend thanks to Mr. Mark Wiltse and ~x. Robert 

Roy of the Dow Chemical Company. 

Summary and Results 

1. A total of ten treatments were made with Kuron during 

the time of the study. 

2. The treatments were applied under varying conditions 

of weed species and population, of water chemistry and hydrography. 

3. The concentrations of Kuron employed varied from 0.5 

to 2.0 parts per million. In one instance Kuron was used against 

water lilies on a one-gallon per acre basis, and against certain 

of the emergents a 3%solution was employed. 

4. At a concentration of 0.5 parts per million, Kuron 

was effective against MyriO~hYllum in 100' x 100' plot treatment, 

and against Nymphaea in who e small pond treatment. 

5. At concentrations of one part per million Kuron 

was effective against Ceratophyllum and Elodea in whole small 

pond treatment. 

6. At concentrations of 2 parts per million, Kuron 

was effective against MyriOP~llum, Nymphaea, Brasenia, Utricu1aria, 

Pontedaria, and Sagittarla. n the case of the latter two genera, 

topIcal applicatIon of a 3%solution of Kuron (Silvex) also 

proved effective. 

7. Concentrations of Kuron ranging from 0.2 to 2 parts 

per million were ineffective against various species of Potamogeton

316. 

and sparjanium. In the case of Sparganium, topical application 

of the ~ solution also proved ineffective. 

8. It was found that generally the effects of Kuron 

could be seen during the first and second week after treatment. 

In some instances this interval was less and in others more. 

During the study, temperature did not appear to be a governing 

factor; perhaps water chemistry may be the important factor here. 

Field 

Methods 

A John Bean 44-K pumping unit was employed almost 

exclusively for the application of Kuron. Generally the Kuron 

was sprayed on the water surface. In several instances where 

the aquatic weed growtnwas below the surface, close to the 

bottom, the chemical was applied by submerging the spray gun to 

a depth of about 3 feet. In the small shallow areas where it was 

not feasible to use a power sprayer, a knapsack sprayer was used. 

It is the author's opinion that good coverage of all areas sprayed 

was obtained. Samples of water were collected for chemical and 

microscopiC examination before and after each treatment. The 

temperature of the water was also recorded. In several instances 

bottom samples were collected before and after treatm,mt and 

examined for bottom organisms. Aquatic plants were collected 

before and after treatment for identification and examination in 

the laboratory. 

Observations were made of the treated areas at semiweekly 

intervals whenever possible. In one instance a daily 

check was made on a treated area and samples of the plants were 

collected for cytological examination at the laboratory. 

Laboratory 

Methods 

In the laboratories of the Lawrence Experiment Station 

the examination of water, bottom and plantssmples were completed 

with no delay, whenever necessary. The biological studies were 

conducted inaqusria, and observations and reSUlts recorded at 

daily intervals, or sooner when necessary. Plants removed fr.om 

treated areas 2 to 3 days after treatment were placed in aquaria 

with water from the treated pond. Plants were periodically 

removed from the aquaria and examined microscopically to determine 

which parts of the plant were aff~cted by Kuron. 

Field 

Observations 

Generally, the effect of Kuron on submersed aquatics 

can be observed during the 'first week follOWing treatment. On 

superficial examination, the plants appear healthy and normal. 

Closer observation, however, shows that the plants have diminished 

in Vitality and elasticity. When the plants are removed from the 

water they appear limp and are someWhat soft to the touch. The

leaves may be easily stripped from the plants with little effort. 

During the third to fourth weeks after treatment, the plants 

begin to settle to the bottom, and the water surface appears 

clear of weeds •. Most of the plants have lost their leaves, and 

bare stems can sometimes be seen uprooted and floating or still, 

attached to the bottom. After one month, most of the plants 

have undergone decomposition and only little evidence of their 

presence is generally found. 

t317. 

In the case of attached fleating vegetation, e.g., 

water lily and water shield, superficial effects of Kuron treatment 

are visible within hours after treatment. The pads of these 

species are covered with brown spots where the droplets of. . 

chemical have come in contact with them. Further signs become 

evident within a week after treatment. The pads th~n begin to 

shrivel and to lose their natural deep coloration. The stems 

become flaccid and lose much of their tension. They appear to ' 

have become elongated and swollen' somewhat and are rather easily 

pulled apart. W:lthin three weeks, the pads have submerged and the 

water appears free of vegetation. During the first and second 

month following treatment decomposition occurs and proceeds , 

quite rapidly. Also during this time a great many of the underground 

stems have dislodged and can be seen tree-floating on the 

surface. Complete eradication is usually assured when this occurs. 

It was found that Kuron at 1 part per million was not 

effective against water lilies when applied during the fall 

(October). The author reasons that treatment this late in the 

growing season fails because of the physiological condition of 

the lily ,pads during this,time of the year. Beingdeciduous 

by nature, all vital functions have probably been arrested by 

this time and consequently the uptake of chemical does not occur. 

This is in contrast to the species of submerged plants such as 

Myriophyllum. which lie dormant during the colder weather but 

are ,still physiologically active although at a decreased rate. 

Kuron proved to be ineffective against various species 

of Potamogeton at concentrations varying from 0.5 to 2 parts per 

million. A 1%Kuron spray was ineffective against Lemna (duckweed). 

No outward signs of susceptibility were noted during the posttreatment 

examinations of these species. 

In treated areas of large ponds' from which Myriophvllum 

and Utricularia were eradicated, floating, healthy piecesrof 

Utricularia from adjacent control areas were noted in the area. 

However, the Utricularia did not take root ,and the areas have 

remained relatively free of vegetation for Ii growing seasons. 

During the study no effect of Kuron was apparent on bordering 

shoreline trees and ornamental plants • 

. A summary of Kuron treatments is shown in Table I.

) 

I 

Kuron 

'I'Ahl .. T _ o£ '17. ---- ~.." 

i 

- 

~-- 

(SUvex:) Aquatic Weed Area Treated WrM'reatmerrt Treatment %nn %Regrallth Renarks 

PFM Growth Date 

-- 

12.Z1 

2. Myriophyll.1n . 100 l x 100 1 Dense 8/13/57 100 o thru 19S8 A sharp line , 

(.25 Acres) -} growth evidenI 

outside area. 

1 • 5 Acres Dense 10/24/57 100 

It 

2 Potamog8tm 0.3 Acres Dense 8/28/57 0 - 

Treatment 

Ineffective 

~ 

: 

2 Mytiophyllmn 4 Acre cove Dense 9/2/SB 100 To be deter- Exam. of 9/15. 

ndned 

showed no evi 

dence of live 

planlis. 

II It 3 Acre Cove Dense • 

It It It 

1.5 • 4 Acres Dense . 10/ll/58 

It It Treated by ha 

(Whole Pond) at 3-day me 

valse 

2 

II 200 t x 50 1 Dense .- 9/2/58 90 

It Spray gun sub 

(shoreline area met'ged below 

surface. 

2 N1JlIPhaea 1 Acre DEnse 9/2/58 100 To be deter.:.. 

ndned 

It It 11 

3.5 Acres Dense 6/28/58 o thru 1958 

I i (Whole Pond) 

I 

i 

------ • 

, 

to . 

rl 

C'\

____ u _______ •• 

( 

K'IlI'

320. 

Laboratory 

Obs;rvation s 

Specimens of MyriO~hYllum collected after Kuron treatment 

were exam1~d micros cop cally to determ1ne the areas and 

extent of tissue damage. It was found that the root , stem and 

leaf tissues were all 1nvolved. The epidermal (outer) layer 

of cells of the root system was spotted with dead cells-evidenced 

by brown1ng and loss of cellular integrity. The stem tissues 

showed similar changes. The leaf tissue showed more marked changes. 

The brown s~otting was more extensive and penetrated theparenchymal 

(deeper) tissue cells to a greater extent. Under oil emersion 

(960 X ma~11'ication~1 some of Vhe leaf celJ,.s werlt observed to 

contain lar~e "brown' masses within the cytoplasm:proper , in 

others the brown" discoloration was restricted to the cell 

membranes. It is conjectured that the ~brown" formations were 

a product ,of cellular coagulation. No attempt has been made to 

determine ~he significance of these findings I since the author 

feels that I\'lore detailed research at the cellular level is 

necessary before conclusions can be reached relative to the mode 

and site of action of Kuron on aquatics. If funds are made 

available t9 continue the present research, it is planned to 

undertake similar studies during 1959. 

The aquatic studies conducted on ~he chemically treated 

plants showed that under laboratory conditions the plants 

succumbed to the effects of Kuron at a much faster rate than did 

the plants which were left in the treated area under natural 

conditions. 

Microscopic examinations of water samples collected 

before and after Kuron treatment indicate that except for a 

moderate initial decrease in the plankton forms, the plankton 

population was not adversely affected by the Kuron treatments. 

Essentially, the same was true of the bot.tom organisms. Here 

again, more detailed study is indicated and necessary before any 

definite statements can be made relative to the effect of Kuron 

on fish food organisms. The fact that eradication of aquatic 

weeds in fish culture ponds is fast becoming a practice , and 

that scientific knOWledge in this area of weed control is lacking~ 

the author faelo that this would be an excellent field tor 

research by interested indiViduals • 

. Conclusions 

1. Kuron (Sllvex) 2 (2,4.5-Trich.lorophenoxy) ;propionic 

Acid shows great promise as an aquatic herbicide and is effective 

against most speoies of aquatic plants at contact concentrations 

of 2 parts per million. The notable exceptions to this appear to 

be the genus Potarnogeton among the submerged aquat1cs, and the 

genus Sparganlum among.the emergents. . 

2. Kuron, apparently, is not a "contact""poison' I but

321. 

must be absorbed 

In view of this, 

by the plants in order to exer~ its toxic 

Kuron may properly be termed an "internal" 

effects. 

poison. 

3. From the observations made of th~: reaction of the 

water illy to Kuron treatments - the resulting elongation of the 

stems - one is led to conclude that Kurona.cts 9S a growth 

stimulating substance, and is properly classed as a plant growth 

regulant along with 2,4-D and 2,4,5-T. 

4. Since areas whioh have been cleared of aquatio 

weeds With Kuron remain weed free for more than one growing 

season, it is concluded that Kuron is capable of residual control. 

5. Kuron properly used against aquatics does not 

adversely affect land plants Which border the treated areas.

322. 

l'ROGiillSSitEi'ORTONTHEUSEOF KURON, 2,4-D and 2,4,5 

ASAQUATICHE,UlICJJJ!ES 

TP GRANULES 

by 

RoyR. Younger 1/ 

Assistant Fisheries Blologist 

N. J. Division of Fish and Game 

The purpose of this report is to summarize the results 

of three year's experimentation using Kuron, and one year1s 

progress in using 2,4-D and 2,4-5 TP granules as ~quatic herbicides. 

The first experimental work with Kuron was conducted 

at il.amapoLake, Passaic County in 1956. y The follo,,1ing year 

thirteen lakes and ponds were treated. The results of these 

experiments have been presented in a previous paper. JI 

At RamapoLake, the herbicide was applied at a concentration 

of 2.5 p.p.m. to control water milfoil, Myriophyllum 

heterophyllum; fanwort, Gabombacaroliniana; and 1.hite water 

lily, Numphaeaodorata. No further treatment was necessary in 

1957, however, in 19$8 the treated areas were completely reinfested 

with the same noxious weeds. 

Good control of the most predominant species - water 

milfoU, i'Iyr i o hYll um sp , , yellow water lily, Nu¥~ar sp., and 

white water li 1y, N,i1liiphaeasp., was obtained in 1.ve ponds receiving 

total applications of Kuron in 1957 at concentrations 

ranging from 0.5 to 2.5 p.p.m. In 1958 these ponds needed no 

further treatment because the water milfoil had not reappeared 

and the water lily stands were greatly reduced. Considering 

the size and extent of the lily root systems it is not difficult 

to understand why total control in one application is not 

possible. 

Plant reinfestation seems most likely to occur, at 

least in NewJersey, from seeds and plant fragments entering 

from untreated lakes upstream, rather than from the germination 

of seeds after the application of Kuron. There is some evidence 

y 

y 

JI 

The author is now employed as a technical representative of 

Halco C2lemicalCompany,Kenilworth, N. J. 

Huckins, Robert K. 1956. Job completion report, Project 

F-l-R, Aquatic Heed Control, unpublished. 

Younger, Roy R. 1957. Preliminary studies using Kuron as an 

aquatic Weed Control Conference, NewYork, January, 1958. 

All this work has been conducted under federal aid in Fish & 

Wildl~fe Restoration Acts, NewJersey project numbers F-10-R

323. 

that nEllvplant species, normally shaded out by dense stands 

of predominant plants, will start to appear once the dominant 

vegetation has been removed. For example, water starlTort, 

Callitriche sp., started to appear in isolated clumps 

along the shoreline in ponds where other species had been 

controlled the previous season. It is doubted that this 

species will successfully infest the pond since it \.Ul be 

crowded or shaded out by a more prolific and faster-growing 

species. 

Plants which were successfully controlled by Kuron 

applications are:- water milfoU, Hyriophyllum sp., fanwort" 

Cabombasp., yellow water lily, Nuphar sp., white water lily, 

Nymphaeasp , , water shield, Brasertiasp., rush, ~ sp." 

water celery, Vallisneria SP." water weed, Anacharis sp." 

cattail, ~ sP., water starwort, Callitriche sp, 

Plants on which limited control "was obtained 

using Kuron are:- bladdenlort, Utricularia sp, and pond 

weed, Potamogeton sp , W 

The factors which seem to affect the successful 

control of aquatic vegetation when using Kuron are:- 

1. I"rater tenwerature 

Cold lTater applications produced 11ttle, if any, 

control. Since aquatic plant growth is at least partly 

associated lnth water tenwerature, it is speculated that the 

cold water reduced the p!ant' s vulnerability to Kuron. For 

tnis reason it is recommended that treatment with Kuron 

should begin when the water tenweratures are in the 60' 5" 

around Nay 15th: in NewJert/6Y. Spraying programs can be 

continued until the flowers are present. It is doubted that 

spraying after the seeds are found will provide adequate 

control on them since Kuron is not a ohemical sterilant or 

a pre-emergent type herbicide. However, the mature plant 

.nIl be controlled. 

2. Contact time 

The contact time necessary for Kuron to produce 

plant destruction has never been determined. It has been 

observed that in those lakes Where water levels were 

~ Results in other states have indicated that Potamogeton 

sp., can be controlled, 'however, this species was never 

controlled in experiment a conducted in NetTJersG,Y.

educed prior to treatment greater plant destruction was 

achieved. Therefore, it is recommendedthat lakes and ponds 

receive total treatment and that the lake volume be reduced 

to insure sufficient contact time. 

The concentrl1-tion recommendedto obtain adequate 

control wi-th Kuron is 2.0.to 2.5 p.p.m. The DoWChemical 

Toxicological Laboratory has determined the L.D. 50 for the 

emerald shiner, NotrotiS atherinoides, is 7.0 p.p.m. The 

recomaended concentra ioft is far below the toxic level and 

fishkills should not occur, providing other chemicals are 

not used before or after treatment. Furthe:more, damageto 

shoreline vegetation ~u:l.d be negligible at this concentra- 

Mon.y - - . 

3. Bottom application 

Spraying the exposed bottom uithKuron at the rate 

of 4 gallons per acre has proven successful in one instance. 

It might be worthl1hile to more fully explore this technique, 

thereby reducing the cost and making it possible to spray at 

an earlier period in the spring. 

Conclusions 

The results of three years of experimentation would 

seem to indicate that longer periods of control are obtained 

~~th Kuron than with other herbicides. 

2,4-D and 2,4,5 TP granules 

As a .result 

of Dr. Grigsby's Y work in Hichigan, 

the NewJersey Division of Fish and Gamebecame interested 

in further field testing of 2,4-D and 2,4,5 TP granules. 

Thirty-six plots containing 2,500 square feet (.057 acres) 

uerelaid out to evaluate the effectiveness -of 2,4-D and 

2,4,5 TP granules of either 15/30 or 8/15 mesh Size. The 

IITPIIgranules were tested in ,three plots and the IIDIIin 

thirty-three plots. 

il There have been some fisi1kilis in the past. In one 

instance the fishkill was caused by the addition of 

copper sulfate for algae control prior to treatment ~~th 

Kuron. Another fishkill _in a farm pond was attributed to 

the rinsing of spray equipment previously used to apply 

Nalathion. A third fishkill has never been explained 

due to so ma~ extraneous faotors ~lhich occurred either 

prior to or immediately following application. 

§! Grigsby, B. H. and R. H. Hamilton, 19S6. Newtecbniques 

in theapplioation of h~rQicides-for control of aquatic 

plants. Presented at the 1958 meeting of the Weed 

Society of America, 11emphis,Tenn. January, 1958.

The IITplI was evaluated at 5, 10 and 15 pounds per 

acre and the "D'' from 10 to 60 pounds per acre. The plants 

in these plots were water milfoil, ~~rioP~llum sp., water 

celery, Vallisneria sp., and pond ,.eea, Po amogeton sp, 

(Table I) For the most part the granules were distributed 

by a cyclone spreader. 

The results of these experiments were very erratic 

and discouraging. Water milfoil and white and yellow lilies 

were the only species controlled. In the areas where control 

'·Tasobtained the plot was quickly reinfested by plant 

fragments drifting in from untreated areas. These .fragments 

would settle to the bottom and develop adventitious roots. 

The water lilies soon developed new leaf and stem systems. 

This reinfestation did not affect the lake's usage since 

the plants did not grow rapidly. There were no fishkills 

and in one instance sunfish were observed making a nest in 

an area ''1hich had just been "sowed" with "D" granules. 

The concentration producing the greatest degree of 

control were the higher ones of 20 to 60 pounds per acre for 

"D" and 15 pounds per acre for TP. There is evidence that 

even at these rates treatment lull be necessary the following 

year. 

The disadvantages of the granules are:- 

(1) The granule size. The 15/30 size mesh 

attaclay produced the greatest problem since they could 

not break through the surface tension of the water because 

of their lightness. A granule of 8/15 size mesh readily 

breaks through the surface tension of the water and becomes 

distributed on the leaves and stems of the plant. 

(2) Granular hardness. The hardness of the 

material used for granules ranged from hard to very soft. 

The soft granules produced a threefold problem. First, 

clouds of dust were given off as these granules were being 

distributed, resulting in some damage to trees along the 

shoreline. Secondly, this dust was inhaled and drowsiness 

resulted to project personnel. Whether this drowsiness is 

associated ,rith the 2,4-D or the attaclay dust has yet to be 

determined. Thirdly, an oil slick appeared on the surface 

of the water immediately follOWing application of the softertype 

granules. Sometests have revealed that the oil slick 

is 2,4-D, thereby possibly reducing the effectiveness of the 

material. 

(3) The time required to bring about plant destruction 

is approximately six weeks. Early spring and winter 

applications have not been made to determine the effectiveness 

_.&' ~\", _ _ ........_ ...., "". __ ,..:1 ... _ ......... __ .... __ ...._ ....4- .... _

326. 

Conclusions: 

The advantage of using granules is ease of distribution 

since no cumbersomespray equipment is required. 

This makes it possible for lake front property owners to . 

treat their portion of the lake. 

If the mechanics of the granules can be improved, 

and if the rates of application can be determined, they 

will definite~ ha~e a place in aquatic weed control.

( 

l'ab Le 1. 

SID1NARYOF 2,4-D and 2,4,5 

TP r::G'B11IHm'lTS IN NlM J..:ftS:.>YFOR1958 

Area treated 

Applegatels Pond 

11onmouthConnty 

Date 

treated 

4/29/58 

Hater . 

t 

Medford Lakes 

camden Connty 4/30/ 58 65 

62 

D.O. 

-10.4 

H 

6.8 

No. plots and 

aut , active 

2.4-D/acre 

No. plots and 

amt. active 

2,.4,5 TP/acre 

plots 

5 lbs/acre 

lOlbs/acre 

15 lbs/acre 

3 plots 3 plots 

10 lbs/acre 5 lbs/acre 

7.4 5.4 20 lbs/acre 10 lbs/acre 

301bs!acre __ _15 1bs/acre 

3 plot;s 3 plots 

~nsconetcong Lake 10 lbs/acre5 1bs/acre 

Horris County 5/9/58 - 63 9.2 6.6 20 1bs/acre 10 1bs/acre 

30 lbs~c_re_n _ 15 1bs/acre 

Hopatcong 

Sussex Connty 

Grovers Ni11s 

Mercer County 

~stevil1e 

At1antic 

Lake 

Connty 

Saxtons FanS 

l farren Connty 

6/12/58 

7/10/58 

8/7/58 

8/5/58 

76 

78 

76 

72 

1.8 

6.8 

6.6 

8.0 

7.6 

6.6 

5.2 

7.5 

rOpIOts 

2 - 10 lbs/acre 

2 - 20 Ibs/acre 

2 - 30 1bs/ acre 

2 - 40 Ibs/acre . 

2 - 60 1bs/acre 

3 plots 

15 lbs/acre 

20 lbs/acre 

25 lbs/acre 

3 plots 

15 lbs/acre 

20 1bs/acre 

25 Ib:;l/acre 

3.·plots 

15 lbs/acre 

20 1bs/acre 

25 lbs/ac::..:r...;:e_· _ 

VJ 

N 

--J

) 

) 

Table I Contd. 

sm'i'iARYOF 2,4-D and 2,4,5 TP ':;yP .nM~'rTS ]}I l'L1" J,;;,{SX }'Oli 1958 

Area treated 

Applegate l s Pond 

Monmouth County 

Hedford Lakes 

Camden County 

Musconetcong Lake 

Morris County 

Type of vegetation 

FanvlOrt, Cabomba spa 

Spatterdock, Nuphar spa 

Hater milfoU, 

tlyrioprojllum spa 

~-!hite water Jily 

N:vmphaea spa 

iJater milfoil, 

f-Jyriophyllum 

Spa 

Control 

None 

i-Tone 

2,4-D control onlY 

with 12 and 18 

Ibs/acre. 

2,4,5 TP control with 

9 Ibs/acre y 

. 

1X) 

N 

C'"\ 

Hopatcong 

Sussex County 

Grovers Mills 

1'1ercer County 

J!:steVille 

~--- 

Lake 

Atlantic County 

Saxtons Falls 

Harren County 

y 

y 

]/ 

Hater milfoU, 

l1yriophyllum spa 

Spatterdock, 

ifuphar spa 

Pond lVeed Potmegetgn 

Famlort, 

Cabomba spa 

Bladderwort 

Utricularia 

1;/ater milvoil 

Nyriophyllum 

At time of application no Vallisneria was obs erved, After treatment and destruction 

of i''ly-riophyllum, the Vallisneria took over th'l treated area • 

Regardless of rates of application, good control .las had ·for a short period of time 

since weed fragments from untreated areas settled to the bottom, putting out advantitious 

roots, thus reinfesting the treated area. 

In these plots the 2,4-D was sprayed on soft attaclay Which broke donn imiaediately 

upon contact with water. 

Spa 

Spa 

spa 

Good control 

all rates y 

at 

None 1/ 

None }/ 

J'ione }/

329 

A PR~Lll~NARY REPORTON THE USE OF 

CHEMICJl.LHERBICIDiS TO CONfROL 

PURPLELOOSESTRIFE(LYThRm~ 8ALICJl.RIA) 

ON A S~~LL I~RSH 

W. H. McKenn, New York Conservatinn Department,Pnughkeepsie 

In the Lower Hudson Game r~nagement District, 23 

wildlife marshes have been constructed under the Pittman 

Robertson program since 1951. These marshes generally back 

up water averaging two and one-half feet in depth over areas 

ranging from three to seventeen aCres. The chief purpose of 

these marshes is to provide nesting and breeding areas for 

wild waterfowl. In order to make this possible, a variety of 

food and cover plants are essential. However, a large percentage 

of marshes in the district have an almost pure stand 

of Purple Loosestrife (Lythrum salicaria) whicnprovides 

little food but does give some cover. 

The marsh chosen for this study is the Traver ~~rsh 

located in Pleasant Valley, Dutchess County, New York. It 

was constructed in 1952 and floods approximately twelve acres. 

The central portion is almost completely dominated by Purple 

Loosestrife with a few sedges interspersed. 

In an effort to find some means of controlling this 

plant so that it might be replaced by more desirable food and 

cover plants, several types of treatment were used. 

Manipulation of water levels was first attempted. 

This was completely unsuccessful. Burning of the marsh in the 

winter was next tried. This too failed as Loosestrife has a 

deep root system and does not burn readily. Surface and subsurface 

cutting was next attempted. This had no effect. Our 

next attempt was with chemical control. We set up several 

study plots of various sizes and used a number of different 

preparations. 

During 1955-58 several chemical concerns donated 

their products for experimental use on the Traver t~rsh in an 

attempt to control this weed. Among the products used in 

1955 and 1956 were Weedazol, Karmex 40, 2-4D, 4-5T and 2-4 Dow. 

In 1958 we obtained sufficient quantities of Kuron to treat 

several one acre study plots. 

All the spray work completed in 1955 and 1956 was 

hand applied on quarter acre study plots. The locations of 

all plots are indicated on the accompanying map. 

In order to facilitate the spraying process on the 

two one-acre plots which were to be sprayed with Kuron during 

1958, they were cleared to ice level by mOWingduring the 

winter. This gave us more maneuverability and visibility for

330. 

spraying since Loosestrife has a dense vegetational habit. 

The dead canes from the previous two or three seasons which 

remain erect form a substantial barrier to a man wading with 

a hand sprayer on his ba.ck. Further the root-stocks form a 

bog like structure which also causes difficulity in wading. 

i'h:.s clearing operation ~"as completed in March of 1958. 

Spraying activities were completed on Plot F on 

June 6, 1958. In this application we used Kuron at the rate 

cf 64 acid equivalent per acre. 

Spraying was completed on Plot G using a 12# acid 

,'q,.ivalent per acre of Kuron on June 12, 1958. 

On July 18, 1958 Plot F was resprayed using 6# acid 

equivalent per acre of Kuron. All ap~lications were mac.e in 

a mist form with no perceptible drift. 

All applications that were made during the entire 

period are tabulated below in Chart 1. 

CHARTI 

Plot Size Date Temp. ~Vind Cloud 

A 1/4 acre 5/9/55 40° 14 NW 90% 

B 

c 

D 

E 

F 

G 

n \I 

7/12/55 85° 4 S 0% 85% 

n n 5/20/55 70° 4 NW 0% 100% 

n n 

5/6/55 75° 12 SW 25% 25% 

n fl 

6/6/55 80° 4 N 0% 80% 

" " 6/8/55 65 0 10 SW 100% 50% 

1 acre 

6/6/5$ 70° 10 W 

7/1$/5$ $0° 10 S 

1 acre 6/12/58 75 0 5 w 

0% 

0% 

0% 

Cover 

% kill* Dosage** Precip. 

1001~ 

100% 

4# per acre None 

(Weedazol) 




(2-4 Dow) 




(2-4D, 4-5T) 


(Karmex 40) 

6# per acre 

(Kuron) 

None 

6# per acre 

(Kuron) 

None 

12# per ~cre 

(Kuron) 

None

331. 

The spray work that was done during 1955 was further 

evaluated in the growing season of 1956. It was found that 

regeneration had taken place so that all plots except Plot A 

were still 75% covered with Loosestrife. 

Further sprayings on Plot A during 1956 using Weedazol 

kept this plot open. However, with the amount of spraying that 

is necessary District-wide, it would not be economically 

feasible to attempt control with this formulation. 

The 2-4 Dow and 2-4D, 4-5T compounds were not sufficiently 

effectibe to be used for the degree of control we 

need. 

used. 

Karmex 40 was not effective at all in the strength 

We do not have sufficient information as yet on the 

plot sprayed with Kuron to determine its value in control. 

We will have to wait until next year's growing season to 

determine its effectiveness even though it gave a total kill 

in the year of application. 

At this time further studies are needed since none 

of the chemical compounds which were used gave us the degree 

of control desired at a feasible cost.

332. 

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333. 

SOMEUPE.,IENCES WITHCONTROLOF PURPLE 

LOOSESTiJ:FEAT THE MONTEZUVJA NATIONALWILDLIFEREFUGE 

Lawrence S. Smith l 

The importance of purple loosestrife, Lythrum salicaria, as a weed 

threat in areas managed.for waterfowl first came to this author's attention 

in the reriod 1954 through 1956 in connection .d.th pool management 

on the Montezuma National Wildlife Refuge. 

Purple loosestrife has been noted to be a commonspecies on wetland 

areas of CentrJl NewYork (Wiegand and Eames, 1925), particularly so along 

the NewYork State Barge Canal in the vicinity of Montezuma and Port Byron, 

NewYork, and on and near the NewYork State Howland's Island GameManagement 

area. This species is commonalong the watershed of the Oak Orchard Creek 

in western NewYork--on the present State GameManagement Area and on the 

area being acquired as the Oak Orchard National Wildlife Refuge. 

Through 1:155,purple loosestrife was noted as occurring outside of, but 

adjacent to, impoundment areas at the Montezuma Refuge. A maximumdrainage 

of refuge impoundments was made during the summers of 1954 and 1955 for the 

purpose of solving a carp problem. At that time purple loosestrife encroached 

into the pool areas. While the preponderance of growth appeared near the 

established stands of loosestrife growing at the foot of dike slopes and along 

the Barge Canal, individual plants were found widely scattered throughout the 

pool area a half-mile and more from any previousl~ known stands of loosestrife • 

. From my acquaintance !,nth Dr. Arthur Cook of the NewYork State Conservation 

Department, I had learned of the problems the state had encountered ,dth 

this species. Dr. Cook pointed out the young plants of purple loosestrife within 

the Main Pool area at Montezuma and briefed us on his failures as of that 

date to control the plant with herbicides where it gre Tt1 in standing water. Once 

established, loosestrife continues to grow from the same root and everrtual.Ly 

forms a stump of sorts at the water line.. !.Ti. th a little age the species takes 

on theanpearance of brush. Its only value to waterfowl is cover, which could 

be better provided by several other emergent aquatics. vlhere loosestrife grows 

in dense stands, it makes an area impenetrable to access by boats and precludes 

the growth of aquatics of more worth to waterfowl. One redeeming feeture of 

this plant in the deeper water portions of impoundments for waterfowl may be 

its ability to survive both deeper water and muskrat actiVity, thereby providing 

cover where other SD8cies cannot exist. The success of this species 

in extending itself throughout wetland areas may Hell be explained by the fact 

that it is an introduced plant of European origin. 

From my discussions with Dr. Cook, it became apparent that while 't1ehad 

the bei~nning of a problem on our hands, this period of initial encroachment 

1. Bureau of Sport Fisheries and 'N1ldlife, U. S. Fish and Wildlife Service

334. 

was going to be the most opportune time to contTol the species, if possible. 

During the early sUlllmerof 1956 we had equipment set up for a?plication of 

AMS(Ammoniumsulfamate, commercially Ammate) on brush. While the use of 

this herbicide on loosestrife had not been reported to me, we applied AMS 

to loosestrife on shoreline areas by truck mounted brodjet aprayer. The 

more dense stands of loosestrife Within the Main Pool area were sprayed by 

mounting our spray equipment within a skiff. Where loosestrife had encroached 

in more widely scattered situations, considerable effort was put forth to 

hand pull the individual plants. This was done by a laborer in hip boots 

pushing a canoe along for removal of the plant from the ~ater. Evidence was 

that the plant would re-establish itself if left to lie in the water. 

lTithin ten days of the application of AMS,the loosestrife recGiving 

this spray appeared quite dead in appearance; and we were encouraged to continue 

with the application of this herbicide to an estimated six acres of loosestrife 

during the summer of 1956. No exact and controlled applications were made. 

The AMSwas mixed as per manufacturers recommendations for use on brush, and 

a wetting agent added. The spray tank was filled at the rate of 60pounds of 

active AMS(75 pounds commercial Ammate) and six ounces of wetting agent per 

100 gallons of water. The objective in spraying was to completely spray the 

loosestrife to the exclusion of other emergent aquatics. The nature of the 

growth of loosestrife that we sprayed makes it difficult to assess the amount 

of herbicide utilized on an acre basis. Our records indicate that it fluctuated 

between 32 and 40 pounds of active ingredient per acre (Smith, 1956). 

Prior to killing frosts in 1956, a new shoot was noted on several of the 

loosestrife plants which had been sprayed and otherwise appeared quite dead. 

This shoot came up from the root adjacent to the original stem and reached 

a hdf"ht of 10 inches «bove the water. Because of this evidence, there was 

considerable doubt about the eventual success of our i~tial spraying with AMS. 

However, we were surprised to find during 1957 a 100% kill of the loosestrife 

that had received a complete coverage of spray. Any living plants within the 

8rLa sprayed could be attributed by location to incomplete spraying (Bauman,1947). 

With this evidence of success, we continued application of AMSduring 

the sUlllmsrof 1951 both during pre-flowering and flowering stages of growth in 

the months of July and August. A total of 7.5 acres was treated. The bulk of 

this application was on loosestrife at locations outside the impoundments for 

the purpose of eliminating tho source of seed. The commercial Ammate X was 

used during 1957 at a mixture of 57 pounds of actdve AMS(60 pounds of Ammate 

X) and six ounces of wetting agent to 100 gallans of water. Our records indicate 

the same application per acre of 32 to 40 pounds of active AMS(Smith 

and Morse, 1957). Results from the 1951 applications with AmmateX were as 

successful as those with Ammatein 1956. A further favorable aspect ofthe 

use of AMSon loosestrife is the fact that AMSis effective throughout the 

growing season. In the pre-flowering stag8, purple loosestrife is difficult 

to identify where individual plants are growing amidst other vegetation. The 

most practicable period to have a spray crew in the field is during the flowering 

period when any laborer can identify the plant. The flowering period is 

in the mid-summer season after the period of most rapid growth when certain 

other herbicides. have a maximumeffectiveness.

335. 

Our biggest problem as nf the 1958 season has been in getting the herbicide 

to the plant. Purple loosestrife has gained considerably the last three 

years ~long roadsides, along canal banks, and in dry marsh situ~ticns--areas 

adjacent to the managed impoundments. This increase is in the nature of many 

individual plants scatt~red throughout other growth rather than solid stands 

that can be efficiently treated with herbicide. The location of most of these 

plants precludes the use of power equipment in applying herbicirles. In some 

instcnces hand pulling seemed more practicable than spraying which necessitated 

covering the ground on foot with the added encumberance of a back pack 

p~~p. Upon attempting hand pulling we learned that plants on dry ground situations 

would break off at the ground leaving the root to re-establish the 

?lant. 

The status of purple loosestrife today at the Montezuma Refuge poses a 

conai.der-abl.e problem to the further management of impoundments on the drawdown 

principle. Drainage for purposes of control of carp has hitherto been 

carried out during the summermonths so that a crop of millet and smartweed 

could be produced for waterfowl foods. It appears likely that a drawdown 

now ],Tith the pool areas surrounded with this species would result in an inv~sion 

of loosestrife with which we oould not cope. Drainage at another season 

would necessitate foregoing a type of management most productive in terms 

of waterfowl food production. 

Another avenue of approach to the control of emergent aquatics is the 

possibility of drowning the plant out. I have no observations to indicate 

to what depth the loosestrife plant would have to be flooded to secure a 

kill. The fact that loosestrife thrives in water depths of 24 inches and 

possibly greater indicates that this practice would not be feasible on the 

bulk of our areas managed for waterfowl. 

In summary, our experiences at the Montezuma Refuge indicate AMSto be 

a satisfactory herbicide for elimination of pur?le loosestrife, both in 

aquatic and terrestrial situations. Hand pulling of loosestrife proved to 

be a satisfactory means of eliminating individual young plants growing in 

water as long as the plant was removed from the water. Hand pulling on 

terrestrial situations was not practicable due to breaking of the stem. 

Loosestrife has continued to increase its foothold on the refuge on 

all areas not covered by permanent water. This poses a considerable weed 

threat to impoundment areas during any future drainage operations. Elimination 

of purple loosestrife as of this date would be most difficult, if 

not impossible, due to its widespread occurrence over areas difficult of 

access.

336. 

REFERENCES 

Bauman, A.C. 1947 The Effects of AmmoniumSulfamate on Emergent 

Aquatic Vegetation. Trens. N.A. Wild. Condo 12:346-354 

Smith, L.3. 1956 MontezumaRefuge Narrative Report, September 

through December, 1956. Unpublished Renort 

Smith, L.S. and Morse, J.S. 1957 MontezumaRefuge Narrative Report, 

September thrmlgh December, 1957. Unpublished Report 

wiegand, K.M. and Eames, H.A. ,1925 Flora.of the Cayuga Lake 

Basin. Cornell University Agric. Exp. Sta. Memoir 92, 

491 p.

337. 

Tec~niques Involved in toe Use of Cnemica1s lor 

Establishing Wildlife C1earingaLl 

H. A. Trumbo and W. E. Chappe11Ll 

niLdlife clear::.ngs and/or food patches are essential management tools 'for a 

numuer of gam~ birds a~d animals. Such areas are valuable from several standpoints, 

i.e., attractiveness, simply as an open area or "playground", to proiTide 

more "edge' or shruby growth, and those planted to agricu1 tura1 crops as a 

source of supplementary foods. A combination of these uses is most desirable. 

Bulldozing and hand labor are the foremost methods of establishing and 

maintaining such wildlife clearing areas. Although these methods have been 

qui~e successful, they are also costly; the two main categories of cost are 

labor and equipment, with a number of factors contributing to each one. 

After preliminary experiments at this station in 1956 and 1957 the possi 

~i1ity of es~ablishing wildlife clearings by use of herbicidal treatments appeared 

~o be economically feasio1e. Monuron pellets applied in June or October resulted 

in good control of woody plants (Table 1). Earlier work by Darrow/ 3 showed that 

large trees could be killed by as low as 10 1bs. (active) Monuron per acre. 

Monuron treatment applied at a rate of 5 gms. per clump of brush in December, 

1957, indicated that this method might be worthy of further trial. The results 

are presented in Table 2. 

Table 1. Stem counts showing per cent of top-kill on plots treated with Monuron 

=..:':..'"=~ - 

June treatment October treatment 

Plot l; 3 Reps. (Av.) Plot 5; 3 Reps. (Av.) 

Bef:Jre After Before After 

Total sprouting % kill Total sprouting % kill 

----- 

Red oa!t 308 65 79 280 49 82 

White oak 73 100 46 3 93 

Chestnut oak l 

Sourwood 261 119 54 273 22C 21 

Pine 7 3 57 9 5 45 

Others 819 .is. 2.! 799 133 83 

Total 1818 345 81 1835 .:.45 70 

11 These studies were supported in part by grants from the duPont Company and 

American Chemical Products, Inc. 

~ Graduate Research Assistant and Plant Physiologist. 

11 Darrow, Robert A. and Wayne G. McCully. Proceedings of the Tenth Annual

Tab~e 2. Stem counts on .I./l.":,}-acresample of wildlife clearing treated witn 

Monuron and Tech T 

Control Monuron 5 gms./clump Tech T 6#-100 oil 

Hand application 

Stem-broadcast 

Stems Stems green Roots Stems Stems Roots 

dead no resprouting resprouting dead resprouting resproutin o 

:~ed oar; 21 3C 28 0 (is 0 c 

,.~ 

'lhite oak 37 47 28 c 55 

v 

C 

Sassafras 3 7 C 0 31 0 0 

:ted maple 5 C 0 0 34 0 0 

Two field experiments were set-up on U.S. Forest Service and Virginia 

Forest Service lands to make the foll~ling evaluations: 

1. The effectiveness of herbicidal treatments as a method of 

establishing wildlife clearings. 

2. Comparison of cost of this herbicidal method to that of bulldozing 

and manual labor. 

3. The utilization of these clearings by game species. 

~~ Count X Experiment 

Tue area selected was one of approximately 2,OvO acres adjoining a series 

af four (4) study areas equally as large and of approximately the same ecological 

composition. These areas or compartments were designed to study the response 

of ~ame species to various methods of habitat manipulation SUC;l as agricultural 

food plots and timber management practices. Clearings had been established in 

two of these compartments by bulldozer and were planted to various agricultural 

crops such as clovers, grasses and small grains. 

The topography of the experimental area varies from relatively level areas 

to those that are quite steep; bounded on the southeast by a very prominent 

mountain range. Predominant tree species are red oak, white oak, chestnut oak, 

red maple, sourwood, table mt. pine, and black gum. The chestnut oaks and pines 

occur on the higher and drier slopes along with several shrub species, i.e., 

mountain laurel, blueberries and huckleberries. Stem sizes vary from seedlings 

to trees with a d.b.h. of 18 inches. 

Ten approximately one-acre areas were selected with tae same criteria used 

in selecting the sites in the adjoining compartments. Plot boundaries were 

established and each clearing was divided into quarters (Table 4). Each quarter 

Jf each clearing was treated with a separate herbicide. Toe selection of 

quarters to receive a particular treatment was randomized. The four herbicides 

chosen were: (1) Monuron on a vermiculite carrier, (2) Fenuron clay pellets, 

(3) Ammate X, and (4) 2,4,5-T. Control areas one-chain square are to be established 

at each clearin~.

Table 4. Design of wildlife clearings;" Broad .Run Project 

.Hill- 

Four chemicals were used in treating. each cl~ring.. Each quarter to receive a 

particular treatment was selected at random. 

All chemicals were applied at shigh' enough concentration to remove all 

woody vegetation on the clearings because. this vegetation is normally removed 

by other methods (bulldozing and manual) employed in creating wildlife clearings. 

Monuron and Fenuron were applied in June' (first application June 5) to 

two quarters of each clearing at the rate of 5 to 10 gms./stem. Stems 5 in. 

d.b.h. and under were treated with 5 gms.·and those above 5 in. were treated 

with 10 gms. Applications were fairly evenly distributed around the base of 

each stem at a distance of several inches from the stem. 

Ammate X and 2,4,5-T were used-in· frill treatments which began August 4, 

1958, and were completed that month. In the use of Ammate, overlapping ax cuts 

were made at waist height around all. tree species 1 in. d.b.h. and above (shrubs 

and tree species under 1 in. d.b.h. were not treated). A solution of 7 Ibs. per 

2 gal. water was applied to these cuts. by Knap sack sprayers and other type 

hand sprayers. 

It was decided to vary the frill somewhat with the use of 2,4,5-T from the 

one used in the Ammate treatment. Ax cuts were made at approximately 4 in. 

intervals on stems 4 in. d.b.h. and above. Those from 1 to 4 in. d.b.h. were 

cut on two sides. All frills were made-at approximately waist height. Tree 

species under 1 in. d.b.h. were stem-foliage sprayed. 2,4,5-T at a rate of 

12 lbs. per 100 gal. oil (#2 fuel oil) was applied with the same sprayers used 

in the Ammate treatment (Table 5). 

Table S. Wildlife clearings, Broad Run Area, acreage/clearing, amount herbicide/quarter 

clearing 

Total amount herbicide/quarter 

Clearing Acreage Acreage 2,4,5-T Aminate Fenuron Monuron 

per quarter 12ft/100 3.5/ga1. 25% 40% 

2 .6 .16 2 gal. 2.5 gal. 12 Ibs. 3.5 Ibs. 

4 1.6 .40 7 4 36 13.5 

5 1.0 .25 3.5 3 20 12 

6 .6 .16 4 3 12 7 

7 .3 .07 1 1 10 3.5 

8 1.0 .25 2 1.5 21.5 

9 .9 .23 2.5 2 40 24 

10 1.0 .25 6 4 24 12 

11 1.0 .25 12 10 15 7 

12 1.5 .38 16.5 lL .22 16

.340. 

On June 27 it ,'las observed that an oY'er-all "brown-out" had developed on 

ehe quarter sections treated with Fenuron and by AUbus~ all species were completely 

defoliated and dead in appearance. 

On the Monuron treated sections a browning effect was noted July 3C and oy 

SeptemLer 17 a majority of the species were defoliated and the remainder was 

i.ii.:Olrln. 

All species ,:>0 t:le Aromai.:ecr eaced sections snowed some browning effect but 

few of the leaves were s~ed prematurely. 

Tilere was no sign of effective treatment on sections treated with 2,'f,5-T 

exce~t for the smaller stems which were foliage sprayed; these appeared to 

nave been Idlled. Apparently the spaced ax cuts were the limitin::; factors in 

this treatment. A spring check will be more conclusive. 

Stem counts were uade and recorded on all sections. A second count will 

be made in the spring in an attempt to determine the effectiveness of each 

chemt ca l , 

~n~ .£2:pJ:.1 Experiment 

An additional field experiment was set-Jp on a tract 0:::State forest land 

on Fort Lewis Mountain, Roanoke County. Virginia, to evaluate different leV'els 

of concentration (1, 2, and 4 gms./clump) of Fenuron. Two replications of each 

concentration were made on areas approximately I-chain square. Treatments were 

made July 24 and 25, 1958, (Table 6). 

Table S. Six 1/10 acre plots. 2 replications. treated with 1, 2, and 4 gms./ 

stem of F:muron 

=.- '===,~.:=:*=='============================ 

Treatment 

1 2;111. 

2 gms. 

4 gms, 

1006-1008 

1002-1312 

816-1087 

-- - _._-._._._-._-.-.- 

* Commercial form clay carrier with 25% active Fenuron. 

**ActiY'e ingredient. 

10,.;70 

11,570 

9,520 

,-----.--- 

Part of this area was heav i l y burned in October, 19:':;;. Al t aough there are 

a number of stems on each ~lot ranging in size from 4 to 10 in. d.b.h., a majority 

is a low growth 5 years old. Except for buffalo nut (pyrular~ ~bera), which 

is parasitic. t;le varladon in species is slight from those on the .Broad Run 

Project Area.

341. 

By October 4, 1958, all species except table mt , (.'ine (Pinus punj,ens) had 

been defoliated. Although the pines had not s~ed their needles they were com 

~letely brown. The plots treated with 1 gm. contained a large number of buffalo 

nu~ which had been defoliated but showed a rebudding tendency. 

Stem counts were made and recorded on each plot and a second count will ce 

made in the sprin~. 

A number of factors must be considered in selecting a herbicide(s) for 

establishing clearings. 

1. Accessibility of areas. 

2. Density and size of ve:,;etation. 

3. Species present. 

4. Equipment used in application. 

5. Cost of herbicide.* , 

": " 

SUMMARY 

From observing the results of the four herbicides used in the outlined 

experiments, it appears that Fenuron and Monuron could be the most successfully 

used in establishing wildlife clearings; quicker results being obtained from 

Fenuron (this is probably due to the soluability of the carrier). Both of these 

ai>pear to be very effective and can be transported to inaccessible areas quite 

easily ina knap sack. No equipment is necessary for the application of these 

herbicides and with some practice approxlmately the proper amount can be determined 

and applied by hand (without the use of a measure). 

It appears that the rates of Monuron and Fenuron in the Craig County ex 

,jer iment ~lere in excess of what was actually needed. Rates, of as low as 1 :,m. 

per stem seemed to give results comparable to the 5 to lO:::;ms. rate used in the 

earlier experiment. 

*The cost of the herbicide to be used will be determined by several of the other 

factors, i.e., accessibility of area, equipment used in application and the 

density and size of vegetation.

342. 

Progress Report #5. Effects of Chemical Brush 

Control Upon Game Food and Cover 

v. R. Byrnes and R. J. Hutnil

343. 

Vegetation on the right-of-way was separated into two layers for analysis. 

A shrub layer was recognized that included all woody vegetation over 3 feet in 

height which makes up the so-called "woody brush" to be eliminated from the 

ri!;ht-of-way. A second layer, the ground layer, was recognized that included 

all vegetation under 3 feet in height. This layer is made up mostly of grasses, 

herbs, and woody shrubs, but may also contain tree seedlings and sprouts 

under 3 feet. 

Treatments 

and Application: 

The six treatments initiallY applied to the original brush on the right-ofway, 

which have been fully described in a previous publication (1), may be 

briefly characterized as follows: 

., _ unsprayed control t'J serve as a comparison with chemical treatments. 

Hand cut in April 1958, six growing seasons after the initial capital 

clearance, by a commercial crew using brush saws and axes. 

B - Broadcast foliage spray of 2,4-D plus 2,4,5-T butoxy ethanol esters, 

half and half, at a concentration of 4 pounds combined acid equivalent 

per 100 gallons of water. Applied June 1953. 

C - Oil water, semi-basal spray of emulsifiable acids of 2,4-D plus 2,4,5 

T, half and half; 3 gallons of spray material to make a concentration 

of 6 pounds of combined acid equivalent per 100 gallons spray in an 

oil-water carrier consisting of 10 ~allons of No. 2 fuel oil in 87 gallons 

of water. fJpplied June 1953. 

D - General summer basal spray of emulsifiable acids of 2,4-D plus 2,4,5-T, 

half and half, at a concentration of 12 pounds of combined acid equivalent 

per 100 ~allons of spray, No. 2 fuel oil being used as a carrier. 

Applied June 1953. 

E - Selective winter basal spray of 2,4,5-T butoxy ethanol esters at a concentration 

of 12 pounds of acid equivalent per 100 gallons of spray, 

No. 2 fuel oil being used as a carrier. Applied February 1954. 

F - Broadcast spray of Ammate at a concentration of 3/4 pound per gallon 

of water; 4 ounces of DuPont sticker-spreader were added per 100 gallons 

of spray. Applied June 1953. 

; ; 

To insure a naximum control of woody brush by each of the treatment techniques 

used, thorough and careful applications were nade. High volumes of 

spray solution as shawn in table 1 were applied to obtain complete coverage of 

the brush. Results of this study and other investigations (2) have shown that 

these high volumes are necessary in the initial application for effective long 

term control with the least amount of respraying. 

Within 2 growing seasf\lJ.s after application, resurge of varying magnitude 

was apparent on all plots. Much of this consisted of seedlings that were 

missed, despite the thorough and careful applications of the sprays, and young 

sprouts that were developing /'In topkilled plants. To determine the value of a

) 

) 

Table 1. SW1IIIIa1'Y of initial treatments and follow-up sprays applied on the power line right-of-way. 

- - - - - - - - - - - - - - - - - - - - - - - Total - Average - -Average- -J~veraie-brush- - Iverage - 

Treatment Number Acreage gallons man hours saw hours truck hours 

_______________ -.R~!i£a!i.£~ _Tre.et~...; Ee! .eere_'y!!r_ll£~ _ ..J>!!r_a£~ __ ..J>~.r_a£~ _ 

A Unsprayed (handout) 4 8.60 --- 39.45 9.39 8.40 

B Broadcast (D + T) 4 8~4.3 460 7.23 -- 2.41 

BD Summer basal follow-up 4 3.48 48 5.20 -- 1.30 

.C Semi-basal 4 10.08 345 7.11 -- 2.37 

CD Summer basal follow-up 4 4.06 20 3.26 -- .81 

D Summerbasal 4 9.82 140 11.61 -- 3.87 

DD SUrrJmerbasal follow-up 4 4.15 21 3.13 -- .78 

E Winter basal 4 10.05 137 16.90 -- 3.30 

ED Summer basal follow-up 4 4.47 138 19.91 -- 4.75 

F Broadcast (ammate) 4 12.65 415 7,05 -- 2~35 

FD Summer basal follow-up 4 4.25 40 4.3:3 -- 1.08 

. 

..:t 

..:t 

C"'I

345. 

quick "follow-up" spray under such conditions, each treated area was subdivided 

into two parts. To one part in each area a summer basal follow-up'spray 

(D) was applied 2 seasons after initial treatment. The chemical used was ACP 

formula 1054-E. It contained 2 pounds of 2,'4-D and 2 pounda of 2,4,5-T per 

gallon and was diluted at the rate of 4 gallons in 96 gallons of No. 2 fuel 

oil. 

The areas receiving these follow-up treatments are designated as B-D, C-D, 

E-D, and F-D. This follo'tr-up spray was applied in July, 1954 except for E-D 

which was applied in June, 1956. 

Unsprayed control plots (Treatment A) were incorporated in the study to 

serve as a conparison with the chemically treated areas in vegetation development 

for game food and cover. By August, 1957 the undisturbed woody brush on 

these plots, which had attained a height ranging from 6 to 15 feet, constituted 

a hazard to power line operation. In accord with original recommendations 

tQ remove this brush when it threatened to interfere with line rraintenance, 

all brush on the control plots was handcut , All stems were severed to within 

3 inches of the ground and the resultant slash piled and burned. 

A summary of treatment application including acreage treated, volume of 

spray solution applied, man hours, truck hours, and brush saw hours for initial 

treatments and follow-up sprays is given for comparative purposes in table 1. 

Control 

2f. 1oJoody~ 

Comparisons of chemical techniques in controlling 'WOodybrush was not the 

primary objective of this study. However, it was important to determine the 

relative effectiveness cf the treatments applied on the woody brush before a 

proper evaluation could be made of the vegetation remaining in the ground 

layer. '\

346. 

Resurge, sprouts and suckers from original stems that have been topkilled 

and seedlings· or seedling sprouts, was studied for five years following spraying. 

For analytical purposes the data have been divided intf'l 2 groupsl (1) 

resurge over 3 feet in height, and (2) resurge under 3 feet. The first group 

will soon constitute a contrf'l problem. Many f'lf the seedlings and sprouts in 

the second group will prf'lbably be destr.oyed by plant competition, animal activity 

and extremeS of temperature. Although it is problematical how many of them 

will emerge from the ground layer, they are still a:potential source of brush 

on the right-nf-way. 

A comparison of the status of living plants over 3 feet in height on the 

various treatment areas in August, 1957 is given in table 3. It should be noted 

that it has been necessary to segregate sassafras, which, Owing to its gregarious 

root suckering habit, may increase so abUndantly on the right-of-way as 

to obscure the effects of chemicals On other species. ~en sassafras is 

segregated in the data, all treatments are shown to have given adequate ~Gntrol 

with a resurge of only 26 to 42 plants per a.cre as compared to 980 for control 

areas. lA'hensassafras is included, the winter basal spray without a follow-up 

shows up as an inferior method for control of that species. The broadcast 

sprays and the semi-basal, on the other hand, when applied in high volumes as 

used in these tests, gave an adequate control of sassafras even without a 

follow-up spray. All treatments when followed by a follow-up basal gave adequate 

control of all species including sassafras'. 

Table 3. fltatus of living plants over 3 feet in height on the test areas 

in August, 1957. 

Species 

--------------------------- 

Total 

Bear other Red Misc. Sassa- Minus 

Treatment Oak Oaks Maple Hardwoods fras Total Sassafras 

------------------------------------,-'--- Nu.mber 

%ngle ~rays 

A Unsprayed 126 408 158 288 1,282 2,262 980 

B Broadcast (D + T) 24 14 0 2 4 44 40 

C Semi-basal 2 2 8 14 2 28 26 

D .Summer basal 14 4 8 8 ··124 158 34 

E l·Jint er basal 8 28 2 4 1,182 1,224 42 

F Broadcast. (tmmate) 2 0 10 16 0 28 28 

Sprays with Follow-up Basals 

BD Broadcast (D + T) 0 0 0 2 0 2 2 

CD Semi-basal 0 0 0 12 0 12 12 

J;lD_Summerbasal 0 0 0 26 4 30 26 

ED Winter basal 0 2 0 4 2 8 6 

FD Broadcast (Allllllate) 0 0 0 2 2 4 2 

---------------------------_._-----------

Variation 

~ ~ Layer Vegetation 

347. 

Following cl~ar~ce of the right-of-way in 1951-52» the sparse veget~tion 

,xisting on the forest flo'.r, stimulated probably by full sunlight and reduceA 

competition for moisture and nutrients, inereased in abundance by 1953 tl'l form 

a dense layer covering 73 to 87 percent cf the ground surface (Table 4). The 

species composition of this ground layer was predomi~ntly bracken fern, vernal 

sedge, mixed woodland herbs and grasses, and the commonshrubs blueberri, 

huckleberry, and deerberry (Table 5). ' 

By ;:ugust, 1953, three months after the initial spraying an early evaluatior: 

of the effect of the various treatments on the grtlUlld layer was possible. 

Observations at this time were limited largely t~ an estimation of the cover 

value of the surviving plants (Table 4). It was readily evident that the broadcast 

foliage sprays of 2,4-n + 2,4,5-T and Ammate had caused a major disturbanci.' 

to the ground layer vegetation, with only enough plants surviving to cover 10 

percent of the ground surface. The semi-basal spray was less severe in this 

respect, leaving a sufficient number of liVing plants to cover 25 percent of the 

surface. In direct contrast, the basal applications caused only a slight change 

in cover value» affecting only those plants growing immediately adjacent to 

sprayed sprout clumps and seedlings. With invasion of the bare areas by other 

plants-mostly fireweed, loosestrife, and grasses-plants of the ground layer 

nearly regained their former abundance within two growing seasons after spraying. 

In 1957, five years after initial treatment, this vegetation has spread 

to ,cover 95 to 98 percent of the ground surface en all chemically treated areas • 

. 'Table 4. Progressive changes in area covered by the ground layer before 

spraying and for 5 years following spraying in June, 1953. 

---------------------------------------- 

May August August August August August 

Treatment 1953 1953 1954 1955 1956 1957 

---------------------------------------- 

Percent 

Unsprayed 87 79 96 84 80 89 

s .Broadcast (D + T) 73 10 79 88 ~6 98 

C Semi-basal 81 25 95 96 98 98 

D .SUllll1B1'" basal 81 75 9$ 96 98 98 

E Winter basal 83 75 95 95 97 98 

F Broadcast (Ammate) eO 10 71 04 85 95 

Species compositiljn of the ground layer was radically changed following 

certain chemical treatments (Table 5). The most notable of these was the broadcast 

Ammatearea which developed an almost pure fireweed community the first 

year following spraying. Tn subsequent years, other plants, especially sedges, 

bracken, and aweetfern gradually increased at the expense of the fireweed, until 

by the fifth year, fireweed occupied only a minor position in the ground layer, 

other important changes were the more gradual develQPment of a sedge-grass com 

Immity following the broadcast spraying of 2,4-D + 2,4,5-T and the temporary, 

less pronounced dominance of fireweed in the year following the semi-basal 

spray. Since the basal sprays were highly selective in their application, they

348. 

Table 5. Dominant plants in the ground layer, before spraying in May, 1953 

and after spraying in August 1954 and Augufft, 1957. 

~ - - -- ---- --- - - -- - -- - ------- --- - ----- ---- 

Treatment 

Doml.nantPlants 

in June ---- -- - -------------- --- - - ------ 

1953 

May Aug. Aug. 

U~ ~~ U~ 

~ - -------- -- -- ---- - ----- ------------- ~ -- 

A.S.!/ A.S. A.S. 

Bracken 2~3 Bracken 3.3 Bracken 3.3 

A Sedge 2.3 Sedge 2~3 Sedge 2•.3 

Unsprayed Mixed Herb 1.1 Mixed Herb 1.1 Loosestrife 1.2 

Blueberry 2.2 Blueberry 2.2 Blueberry 1•.3 

------- ---- -- --,- -- ------ ---- - ----- - ----- 

Bracken 2.3 Sedge 2•.3 Bracken 2.3 

B Sedge 2.3 Grass 1•.3 Sedge 2.4 

Broadcast Mixed Herb +~l Mixed He:r;b 1.1 (lrass 1.3 

(D+T) Blueberry 1.2 Bracken l~l Loosestrife 1.1 

Blueberry H.l Blueberry .+.2 

- - ------ --------- ---- - - ---------- -- - - 

Bracken 2.3 Fireweed Z.2 Bracken .3.4 

Sedge 2.3 Bracken 1.2 Sedge .3.4 

C Mixed Herb +.1 Grass L2 Loosestrife 1.1 

349. 

The long-time trend on all plots has been toward the development of a 

plant cOl\lllUnity siinilar to the one existing before spraying. The outstanding 

exception was the practical el1m1nation of blueberry and huckleberry on 

the broadcast and semi-basal aJ:'eas.. In addition, the herbaceous plant loose- 

strife had increased in abundance by 1957 to dominate the mixed herb category 

in all treatment areas including the unsprayed control. 

Utilization. 

2! ~ Layer ~ ~. ~. Animals 

As pointed out in the previous section, several important changes occurred 

in species composition of the ground layer following certain chemical treatments. 

Tn three treatment areas (B, C, and F) temporary plant cOlllllUnities 

with one or more domi.nant plant species developed and remained promi.nent for 

1 to 4 years; while on other areas (A, D, and E) the original composition of 

bracken, sedge, mi.xed herb, and blueberry remained essentially unchanged. To 

fulfill the second major objective of this study it was necessary to determine 

the value of these plant cOlllllunities for game tood and cover. This was 

accomPlished by reviewing published reports and making direct observations 

in the course of this study. utilization of the commonplants found. on the 

right-of-way is suminarized in table 6. 

It is readily evident that the plants most frequently used by the four 

animals listed - deer, rabbit, grouse, and turkey - are the woody shrubs, 

blueberry, huckleberry, and blackberry; the sedges and grasses; and the herb 

sheep sorrel. All parts of these plants are reputedly eaten during some 

season- of the year, with deer and rabbits feeding mostly on leaves and stems 

while grouse and twkey feed heavily on buds and fruit. 

Bracken fern which has become the major ground layer plant on all treatment 

areas (Table 5)-has'a relatively low food value with practically no usage in 

the winter, high usage by grouse in the fall, and low usage by deer in the 

spring and summer when the fronds are tender. Fireweed which dominated the 

broadcast Ammate areas for 3 years and the semi-basal areas for 1 year has 

little known food value~'eXcept for- occasional browsing of young plants by 

deer in early spring. The herb loosestrife 

t 

most abundant in the mixed herb 

category in 1957, 'also has low utilization in the Spring BIld summer and virtually 

no value in the fall and winter. Other plants listed in table 6 are 

intermediate, showing high utilization in at least one season of the year. 

The most important comparison between dominant plants present in 1957 

(Table 5) and utilization of plants by game animals (Table 6) is the relatively 

high usage of blueberry and its very low abundance on the semi-basal and broadcast 

spray areas. In contrast to this, blueberry has retained its former 

abundance on the unsprayed control and basal Spray plots. In addition, on the 

unsprayed areas of treatment f. the woody brush of the shrub layer supplies a 

surplus of browse for deer 'and rabbits.

An intensive study of wildlife en the right-of-way was made during the first 

year after spraying by a wildl1.te specialist. At this time, concentrated observations 

were made on all treatlllElnt areas during both day and night periods. 

Additional data were recorded in aubaequerrt years during special surveys of the 

entire right-of-way test area in the winter months at various intervals after 

snowfall. This information was further eupplemented by observations made during 

the course of other work on the right-of-way. The more important wildlife 

species or signs observed on the right-of-way during the 5-year period of this 

investigation are given in table 7. Tt should be pointed out that other animals; 

such as, f~x, racoon, woodchuck, opossum, skunk, and the like were also evident 

on the right-of-way. However, since these are not 1mpo:rtant upland game animals 

thev were not '1nt!lllr!."d in th" analvAi,q. 

350' 

Table 6. Commonplants occurring in the ground layer on the power line 

right-of-way and their utilization for food by the game animals, 

deer, rabbit, grouse and turkey. 

-----------------~---------------------- 

utilizatio~/ by Seasons 

Common ---------------------------- 

Plant Spring Summer ':., .. Fall ,,-Winter 

---------------------------------- -- - --- 

Grasses and Sedges 

Vernal Sedge H H L H 

L L H L 

H H H H 

Panic 

Other 

Ck'as! 

Ck'asses 

Ferns 

Bracken L L H 

Herbs 

Loosestrife L L 

Fireweed 

L 

Sheep Sorrel H H H L 

Cinquefoil H H L L 

Violets H L H 

Herbaceous Smilax H L H L 

Shrubs 

Blueberry H H H H 

Huckleberry L H H H 

Teaberry L L H L 

Sweetfern L ... L H 

Blackberry H H H H 

"litch-hazel L L H H 

!./ H· high utilization. 

L • low utilization. 

Nildlife Observations .2!!~ Right...of"May 

To complete the picture it is ne,essary to know what wildlife animals were 

present and with what frequency they visited the rightoo()f-way. This was accomplished 

in two ways; first, by dire,t observations of the animals themselves; 

and secondly, an indirect determination of their presence as shown by pellets, 

tracks and evidence of feeding.

351. 

A. number of important trends of wildlife distribution by treatment areas 

are apparent from the recorded data. To begin 'With, it was immediately evident 

that deer, rabbit, grouse, and squirrel visited all treatments and that turkeys 

were observed on all but the unsprayed control plots. Deer and rabbits used 

the control areas of treatment" more heavily than the chemically treated areas, 

probably because of the availability of woody browse and diversified cover conditions. 

Numerous deer beds were observed under the protection of dense sprout 

clumps in these areas. In general, the population of deer and rabbits progressively 

increased on the right-at-way in all treatment areas during the period of 

this study. 

Grouse observations were fairly. uniform on all areas with no special pattern 

developed. In most instances when grouse were observed~ they occurred along the 

edges or in the forest imm,"diately adjacent to the righ';:.-of-wE.y, Turkeys were 

most frequently obcei-ved en the broadcast spray areas of tl'eatment Band F where 

grasses and herbs dOlllinated the vegetation. Insects commonly associated with 

such grassy openings apparently attract the young turkeys. 

Table 7. Commonwildlife speeiesor signs observed on treatment areas from 

1953 through 1957. 

---------------------------------------- 

Treatment Deer Rabbit Grouse Turkey Squirrel 

---------------------------------------- 

Number 

A Unsprayed 83 51 12 0 6 

B Broadcast (D+T) 45 8 8 31 2 

C Semi-basal 62, 3 7 1 6 

D SUllll1l€rbasal 53 12 5 1 8 

E "linter basal 59 25 8 1 11 

F Broadcast (Amm9.te) 69 7 8 15 18 

Total 3n 'i56 ~ 49 51 

---------------------------------------- 

The use :)f pellet counts as an indication of the degree of usage of the 

right-of-way by wildlife was initiated in 1954. All pellets on 20 transects, 

3 feet wide by 100 feet long, for each treatment area were counted and removed 

in March or April of each year.· Correlations of number of pellets 'With animal 

populations have not yet been DjlLde. In general, however, the numbers of 

pellets recorded agree very closely with the direct observations on animal usage 

as given, in table 7. Although there were considerable numbers of deer and 

rabbit pell'ets On all areas, the .count.a were highest on the control areas. 

Literature 

Cited 

1. Bramble, ~'T. C" am W. R. Byrnes. 1955. Effect of certain commonbrush control 

techniques and materials on game food and cover on a power line rightof-way 

No.1. Pa. Agr. Expt. Sta. Progress Report 126. 

2. Byrnes, "T.R., ~'I.C. Bramble, and R. J. Hutnik. 1958. Effect of volume of 

spray upon topkilland resurge of oak-enapl.e brush. Proe , 12th Annual ~Cl 

pp. 230-238.

Basically. the TRICXLERis a 2-gallon can carried on a man's back. 

from ,

Basal spray is not 1"1ell suited to the killing of conifers. Apparently. 

there is so much cork tissue in the bark that excessive 

amounts of Chemical are reqUired to saturate it before the cambium 

can be effected. Amongour Northeastern evergreens, only pitch pine 

will sprout; the rest can be easily and completely deadened by the 

appli cat1 on of sod! Ulllars eni t e. On hardl"10ods, basal spray is a Sl011 

but certain method for aChieving total death. Where the requirement 

353 

flexible spout on top prevents slopping as the worker moves about 

but admits air as the liquid is ~,ithdra~rn from the tank. The tube 

connecting tank to wand is of plastic, and kerosene-proof. However. 

it is muChtoo stiff to work easily in the valve, so a short length 

of pure latex tubing - flexible but not proof against kerosene - 

is inserted. When this "'1eak link fl deteriorates it can be replaced 

in a matter of minutes. The cost of parts is nominel;some are 

readh1-obtained salvage material. others can be bought for a dime 

or a half .dollar. It can be assembled in en hour or so with simple 

hand tools and maintained 11ith a pair of pliers and a pocket knife. 

There are no parts to ~et lost and the TRICKLERis practically 

indestructable. 

The Specification Sheet indicates hOI"the TRICKLERis assembled 

and '1here and for how much the parts 

and/or boring the pieces, the nipple 

can be obtained. After 

is inserted in the can. 

cutting 

the 

can and clothes""Pin attached 

The valve is attached to the 

to the 

handle, 

backboard 

the ~,and 

and the harness strung. 

inserted and the tubing 

assenbled. The ferrule of the plastic tube is fitted over the nipple 

on the tank and clinched 'rlth a twist of soft iron wire. Screw the 

flexible spout on the top of the tank and the TRICKLERis ready for 

use. 

The basal spray formulation that I have used with great success 

contains 5 fluid ounces of Esteron 245, a level teaspoonful of either 

Red-O Oil Dye or Sudan Orange as an indicator. and enough kerosene 

to make two gallons - essentially a 2 percent solution. This is 

transported to the site of operations in 2-gallon oil cans. which 

weigh only li pound - light. tight and relatively unbreakable. To 

fill the TRICKLERthe valve is snapped shut and the wand clipped into 

the clothes-pin holder. the flexible spout is unscrewed and put on a 

stock can. 1mose contents can then be entirely poured into the tank. 

Put the spout back on the tank and the rig is ready. 

To operate, the tip of the wand is placed against the base of 

the stem to be treated. the valve is unlatched and thumb pressure released 

to give the,desired rate of discharge. A slight squeeze shuts 

off the flow. ,mile a little additional pressure will latch the valve 

shut.' " 

Maintenance is very low. The latex tubing link at the valve will 

ultimately absorb. sl"1ell up and come loose from the aluminum tubes. 

At the first sign of sl-lelling. it should be replaced. The aluminum 

wand will eventually accumulate a coating of dried-on chemical; this 

can be cleaned out with a ramrod made from a l"1ire clothes hanger ,

354 

It is ~ell known that plant honnones such as 245T are effective 

only at the ~oint of application and that they are not translocated 

very far. Death of the tis~e actually treated results in a girdling, 

~lhich causes the death of the parts above it. A stem girdle WILL NOT 

cause the death of the stump and its associated root-collar buds. if 

such be present. The trick, then. is to flood the base of the stem "'1ith 

enough. chemic all so that it thoroughly ,,,,,ete the above-ground bark and 

fl0\1S d0\1Il onto the thinner bark underground, Only enough of the base 

of the stem need be treated to show what trees have been worked on; 

six inches is qUite sufficient. The TRICKLERdoes this much better 

than does any sort of pressure sprayer because it qUickly ap~lies a 

relatively large volume of l1quid, so that the rundown and lateral 

spread is complete. The result is to effectively deaden the root crown 

and to separate the roots from the stem and from one another. The tree 

is killed, root and branch. and there ,1111 be no sprouting. By treating 

the base of each stem and all the exposed roots. it is even possible to 

kill most of a patch of beech root-suckers. so that a second application 

can complete the job. 

fhe TRICKLERis a simple, rugged, cheaply constructed and easily 

operated gadget ~Ti th which to apply basal spray. When correctly used, 

it ,·Till achieve a very nearly complete kill of susceptible hard"roods. 

within the limit of efficient use for plant hormones. 

Bill 

of Materials. 

1 Backboard,;'11 p11l'100d, 12"' x 16 ft • bored as per sketch 

$.24 

2 Clothesline. 8' 

No cost 

3 Flexible spout. to fit 2-gallon can (Auto Supply) 

$.29 

4 Spring-type clothespin 

$.02 

5 Sheet metal screws (6) 

No cost 

6 Lubricating oil can. undented. 

Salvage 

7 Nipple. 1/8 Ii • ,-lith 2 nuts and 2 steel ,·rashers. 

(Electrical Supply) 

$.10 

8 Toothpaste tube. empty 

Salvage 

9 Zoller Harris Flush Tube IZ-700 (plastic) 

(Zoller Chemical Co., Los' Angeles or Surgie.al Supuly) $.50 

10 Pure latex tubing, i- ft scant inside diameter. 1 yard, 

used for handling blood. (Surgical SUpply) 

$.50 

11 Clip valve, to fit latex tubing. (Surgical SUpply) 

12 Handle. 1 11 $.15 

X 2" X 9 ft , soft,100d 

13 Aluminum tubing. !ft o.d., 24 11 Salvage 

(Auto Supply) 

(Cut off 111for tubing link) 

$.50 

14 Box nails. lin cut to 3/4 ft (2) 

No cost 

15 Stovepipe ',lire, 2 ft No CORt 

$2.30

I'nstroci:fCins tbt: A~S~biing TRICKLER 

Cut and bore backboard "(iJ andh,and.ie (12). Bore clothesnin (4). 

:Bore lubricatizlg d11 can' (6)'; being Sure to file off burr on inside of 

hole. Assemble nipple (7): nut. steel washer. lead Hasher cut from four 

thicknesses of toothpaste tube (8); drop t~ro from inside, put on eteel 

washer and nut. draw up TIGHT. Thread clothesline harness(2) thro holes 

"in backboard (1). knot ends •.. Attach lubricating 011 can assemb11 

~ (6+7-1-8)to backboard (1) wi th.4 sheet metal screws (5). catching the 

flanges of the can. top and Dottom.under the screl" heads. Plece clip 

valve (11) in place on handle' (12). attach the box nails (14) at either 

end. catching clip under nail heads. Insert aluminum tubing I"end (13) in 

handle. so that it sticKs throl" toward clip valve. Cut plastic tube 

(9) to 36 11• insert 111aluminum tubing link cut from (13). insert other 

end of link in 4 11 piece of latex tubing (10). thread free end of latex 

tubing thro back of handle and thro cUp valve, slip over end of 

aluminum tube. Slip ferrole of plastic tube (9) over nipple (7' on can. 

clinch \rl.th a twist of stOV8pi:p8 wire (15). RemOve cepftom can (6). 

replace \'lith flexible spout (3). Adjust fit of TRICKI.ERto worker with 

clothesline harness (2) and by shortening plastic tube (9) if necessary. 

/ 

/ 

• 

( 

T 

o 0 

..... --, --,---J 

1i

356 

Chemi-Thinning Hardwoods in the Dormant Season 

by 

Robert R. Non'ow 

Department of Conservation, Corne.ll Universi ty 

The several herbicide concentrates of 2,4-D and 2.4,5-T offer·new tools 

for chemi-thinning or TSI work in forest stands. While slower in action and 

more expensive than sodium arsenite, these hormone compounds are still relatively 

cheap and effective if properly used. In addition they are very low 

in toxicity and effective when applied in the dormant season. 

Basal spraying of trees with low volatile esters of 2,4,5-T in oil is 

now accepted practice for small stems, particularly where sprouting from the 

root collar is a problem. Results vary according to how well the root Collar 

is soaked with spray. However, large stems require more chemical per inch of 

diameter than small stems; also, white ash, basswood, and sometimes black 

birch are notably resistant (5). It is generally conceded that frill treatments 

for deadening tree tops are cheaper than basal sprays when tree diameter 

exceeds 4-5 inches. 

Prilling 

Considerable research in dormant frilling of hardwoods, especially beech, 

has been done since 1950 on several hundred trees at Cornell's Arnot Porest 

in southern NewYork. Some of the results have been published elsewhere (5). 

In all cases, "frilling" means a series of single light cuts through the bark 

made by a light axe. The outstanding result is that top kill of most trees 

was assured only wi th a complete frill, irrespective of the chemical used. 

Such top kill apparently resulted from a chemical girdle caused by deadening 

of the wood immediately above and below the frill. Where seaas, fire scars, 

or other deformities prevented a complete frill in beech, the tops remained 

alive for years; in vigorous trees, new callous tissue sometimes bridged the 

girdled region and the trees recovered. 

The particular chemical used, while apparently having little effect on 

eventual kill, does influence the amount of deadening around the frill and 

may be important in preventing bridging of dead wood by particularly vigorous 

trees. The chemical also affects the time required for top kill to become 

complete. A test made in October 1953 on beech on a good site is illustrative. 

Where 20# ahg (acid equivalent per one hundred gallons of diluent) 

2,4,S-T ester in kerosene was applied at a rate of 2-3 mI. per inch of 

diameter (a small volume compared to that used in most tests reported in the 

literature), a girdle of dead wood was formed which extended at least two 

feet both above and below the frill. Pive years after treatment, ten of 

eleven trees (4-13" d.b.h.) were top_killed. Of six trees of similar size 

treated with either kerosene or gasoline only at a rate of 3 ml. per inch 

of diaaeter, the girdle of dead wood rarely extended over one inch above 

and four inches below the frill. After five years, half of these trees were 

to~killed, and the other half nearly so. Treatment with 80# ahg 2,4-D ester 

in kerosene at a rate of 3-4 Illi. per inch of diameter gave only li ttle better

In all of the above treatments, the frills completely encircled the 

tree. Except where nothing was added to the frill, there is a girdle of 

dead wood and eventual 

2,4,S-T in oil adde4,to 

top kill",is 

frills in 

assured. The reSUlts indicate 

the dormant season will usually 

that 

cause 

complete top kill in three to six years. Probably an average of two more 

yeats are required where 2,4-Din oil or oil alone is used. Usually, but 

'not always, the bigger and more dominant trees hang on longer. In some 

cases it is possible that root grafts prolong the life of the tree. On the 

other hand, extreme drought conditions may contribute to complete top,kill 

within two or three years, even where oil alone is used in the frill. Such 

appeared to be the case where, the above treatments were replicated in 

November 1956 on a droughty site in a region where severe droughts were 

commonfrom 1954-1957. 

Further frilling 

be deadened by frills 

tests at the Arnot indicated that most hardwoods can 

more quickly than beech. An October treatment of 40# 

ahg 2,4,5-T ester in kerosene at a rate of 3-4 mI. per inch 

made on trees ranging from 4 to 13 inches d.b.h. on a fairly 

of diameter 

good si teo 

was 

flor 

most trees the number of years for complete top kill to take place were as 

follows: 

Sugar maple (30 trees) - 3-4 years 

Black birch (IS trees) - 1~3 years 

Basswood (15 trees) - 2-4 years 

White ash (3 trees) - 2-3 years 

Other tests have shown that these too are top-killed by frills wi th oil .lone. 

There appears to be little difference in frilling results from one part 

of the dormant season to another. ReSUlts from treatments on beech in every' 

month from October through JIlarch were similar. ~les probably should not be 

treated in late winter when there is a possibility of sap flow which might 

flush the chemical out of the frill. ' 

McQuilken (4) has recently' repor ted on reSUlts of frill' treatments made 

in the growing season in Pennsylvania. In general his treatments consisted 

of lower concentrations, but bigger dosages, than were used in the Arnot work. 

Even though McQuilken's results are not final (they included results of only 

three full growing seasons after treatment), it is interesting to note several 

similari ties between growing; .eeason and dormant season frilling. The kind of 

chemical and the concentration used were not:',overwhelminglY decisive in ,determining 

results as far as tested •. Species sensitivity was similar; i.e., 

black birch was most quickly deadene~ while beech and sugar maple were more 

resistant. Also the bigger and more dominant trees were more resistant. 

McQuilken obtained at least 80 percent kill in beech. red maple, and sugar 

maple in three years; thus, summer treatments appear to be somewhat faster 

acting than dormant treatments.

358 . 

The cost of chemi-thinning with frills is mostly labor. In the work at 

the Arnot, where tree diameters ranged from 4 to 15 inches, chemi-thinning 

was done at the rate of I,OOOdi8llleter inches in four man-hours, exclusive 

of tree marking time or time for travel to and from the job. This agrees 

SUbstantially with time reported by Lotti (3) for similar work at the Southeastern 

Porest ,Experiment Station where an average of 77 trees per acre 

(average 9M.d.b.h.) were treated on 13 acres in 37 man-hours. One gallon 

of chemical is sufficient to treat 1,000 diameter inches and, for 2O#ahg 

2,4,5-T in kerosene, the cost is about 80 cents. Thus, if labor is $1~'o 

per hour, i twould coat about $6.80 per 1,000 diameter inches or about aeven 

cents to eliminate a 10 inch tree.' McQuilten (4) reviewed several reports 

giving cost of frill treatments, and these in general agree with the Arnot 

results. The use of oil only in the frill would reduce the total eost by 

only about ten per~ent; therefore it may be wiser to use 2,4 ,S-T to both 

assure and speed up the release of drop trees. 

Spaced Cuts 

There have been some attempts to lower the labor cost of chemi-thinning 

by applying the chemical in wounds or cuts spaced evenly around the tree, 

leaving from one to four inches of live wood between cuts. Rushmore (6) 

recently reported this as a successful technique with sodium arsenite. There 

have been differing reports from southern United States, but under some 

circumstances there has been success in applying high concentrations of 

2,4,S-T in wouDdamade by tree injectors. Gleason and Loomis (1) and 

Westing (7) in the Midwest,and Leonard (2) in California, have also reported 

some success using undiluted 2,4-D amine in spaced cuts. In most cases, 

successful treatments were made at times when the ttees were not completelY 

dormant. Several oaks, which apparently are relatively susceptible to 

hormones in cuts or frills, have been the trees most commonly killed by this 

method. Leonard, Gleason and Loomis, and Westing all reported that 2,4-D 

amine was superior Doth to 2,4,5-T amine and the esters of these chemicals. 

At the Arnot, undiluted 2,4-D amine was used in axe cuts, each separated 

by a space of about ~o inches, at the rate of 2-3 mI. per cut or 1-2 m~. per 

inch of diameter (ca-parable to amounts used by the above-named workers) on 

many hardwoods during the dormant season. A band of wood was killed verticaUy 

up and down frOli each axe cut. but a band of Uvewood remained between each 

cut. The band. of dead woodusua1ly became more narrow above the cut and 

gradually merged into all live wood. A few overtopped or intermediate trees 

were killed, and SQDecrown damage occurred in mor&vigorous trees. ' In general, 

howevet, average crown reduction was only about 30 to 40 percent for most 

hardwoods. An exception i. aspen (both trembling and big-tooth), which was 

top-tilled within a year by this treatment. Por most northern hardwood 

species, this demonstrates onee again the necessi tv of making a cOl1lplete 

frill to obtain good·top kill bydormarit treatments.

Summary 

359 

Dormant frill treatments on hardwoods were successful where the frill 

was complete and chemical was added to cause a girdled area of dead wood.. 

The chemical used was of secondary importance, but 2,4,5-T caused a wider 

girdle of dead wood and quicker top kill than oi 1 alone. Tree vigor, root 

grafts, or poor growth conditions may also considerably affect the time 

required for complete top kill. Dormant frilling was slower in action than 

summer frilling; spring frilling may give poor reSults because of excessive 

sap flow. Aspen is an exception and can be top-killed by 2,4-D amine in 

sPaced: cuts. 

Li terature 

Ci ted 

1. Gleason, L. S. and W. E. Loomis. 1954. Basal sprays and injection 

treatments on trees. Proc. North Central Weed Control Conf. 11:102-104. 

2. Leonard, O. A. 1957. Effect of phenoxy herbicide concentrates applied 

to cuts of sprouting tree species. Weeds 5:291-303. 

3~ Lotti, T. 1957. An effective control for cull hardwoods. Southeastern 

P.E.S. Research Note lOS. 

4. McQuilken, W. E. 1957. Prill treatment with 2,4.5-T and 2,4-D effective 

for killing northern hardwoods. Northeastern P.E.S. Station Paper No. 97. 

5. Morrow, R. R. 1957. Chemi-thinning of hardwoods during the dormant 

season. Proc. Northeastern Weed Control Conf. 11:196-202. 

6. Rushmore, P. M. 1958. Sodium arsenite in spaced ax cuts: an effective 

stand-improvement technique. J. Forestry 56:195-200. 

7. Westing, A. H. 1955. Effects of undiluted 2,4-D and 2,4,5-T in cut 

surfaces on oak in lower Michigan. North Central Weed Control Conf, 

Ann. Research Report 12:168.

360 

A I'ii.OnnsS ~Fo.~T ON rssrs ~i' 

CONTROLLIN'1JAPANESE HONEYSUCm 

S. Little!! 

Summary.--Japanese honeysuckle deter. forest management 

in some parts of ~aryland, Delaware, New Jersey, and 

Pennsylvania. Grazing and burning are not effective in 

controlling this vine. ,Herbicides (ACP-977, !mitrol, and 

2,4-D) tested as foliage sprays kill it back but do not 

eliminate it--even after 2 or 3 treatments. Foresters 

have yet to find a practical treatment for eliminating 

honeysuckle. 

Control of Japanese hon~ysuckle (Lonicera i1apo·nica) is a 

growing problem in forest management in eastern Maryland, Delaware, 

southern New Jersey, and southeastern Pennsylvania. HoneYsuckle 

may form a dense cover on the ground; it may wrap around and climb 

trees and shrubs, often bending down and deforming sapling trees. 

Its growth is par.ticularlyluxuriant in openings, where it usually 

prevents reproduction of other vegetatioQ. -Foresters often hesitate 

to harvest trees on sites where it occurs, because of fear that 

honeysuckle will prevent reproducing a forestlltand. 

Although found in some pine stands, honeysuckle is most 

troublesome on the best hardwood sites ,those that. sho,uld be growing 

yellow-poplar and sweet gum. Maryland foresters found it on 8 percent 

of the sites examined in their upper Coastal Plain and Piedmont (2). 

Honeysuckle probably occupies similar proportions o.f the forest land 

in northern Delaware, the Delaware Valley section of New Jersey, and 

southeastern Pennsylvania. 

Consequently,· in 1957 and 1958 certain aatertais that have 

been recommended for controlling honeysuckle were tested by the: 

Northeastern Forest Experiment Station in cooperation with the 

~aryland Department of Forests & Parks and the New Jersey Department 

of Conservation. 

!/Northeastern Forest Experiment Station, Forest Service, 

U. S. Jepartment of Agriculture, New Lisbon, N. J.

361 

The Athens-wacon Research Center of the Southeastern Forest 

Exp~riment Station has screened many chemicals for their effectiveness 

on honeysuckle. That Center has recommended two: ACP-977 and Amitrol 

(I, 3). The former is a 2:1 mixture of the butoxy ethanol esters of 

2~4-D and 2,4,5~T, the latter contains 50 percent of the 3-amino cl,2,4 

triazole wettable powder. Some other investigators, such as Walker 

(i), have recommended 2,4-D. 

All three chemicals were tried in our tests. The amounts of 

ACP-977 and, ~itrol followed the first Southeastern Stationrecommendations 

(3),' the amount of 2,4-D acid was equivalent to the acid content 

of ACP-977. Water was usually used as a carrier for the sprays. Two 

amounts, 1~5,and 250 gallons per acre, were tried because the first 

Southe~stern'Station recommendations called for 250 gallons in using 

ACP-977'iU5gaJ,lons'in applying Amitrol. 

'\7hile,pl'incipal emphasis -was placed on testing prior'-'recommendations, 

a'few modifications were also tried in both years--primarilY on 

an expi~ratory h~is. 

, . 

1957 IVork 

LOCATIONANDTREAT~NTS 

1957 PLOTS ,,' . 

Seventy-two 1/40-acre plots were established in 1957--24 near 

Green Bank, N. J., 24 on the City of Baltimore's Lock Raven Watershed, 

16 on Contee Farms property near Edgewater, Md., and 8 near Havre de 

Grace, ~d. These plots sampled conditions that varied appreciably, 

as follows: 

1. Green Bank plots in a loblolly pine plantation: 

a. One series in a light cover of honeysuckle. 

b •. One series in a medium cover of honeysuckle. l Each series 

included some plots that were burned by a light controlled 

fire on March 13, 1957. ' 

Lock Raven plots in three blocks, one each in: 

a. A very heavy cover (waist high) of honeysuckle under 

silver maple and boxelder. 

A lighter cover of honeysuckle in a stand of planted red 

'pine, redcedar, and dogwood. 

c. A cover formerly similar to b, but burned by a very hot 

wildfire on April 28, 1957. - 

3. Contee Farms plots in two blocks with relatively light covers of 

honeysuckle under a yellow-poplar stand: 

a. One block in an area not previously grazed. 

b. One,block in an area grazed by cattle, but from which 

cattle'were excluded after the initial spraying. 

,.

4. Havre;de 'Grect! ploht a light cover of honeysuckle in a yellow;' 

popl~'stand. 

Each karyland block was composed of 8 plots, 6 treated and 2 

controls. Spray treatments in june on 1/40-acre pltits we~e (1) l/~ 

pound a~id of ACP-911 in 12.5 quarts of water, (2) 1/5 pound acid·of " 

2,4-D,in 12.5 quarts ot water, (3) 1/4 pound of the commercial Amitroi 

in 12.5 quarts of water, and (4~6) same amount of ACP-977, 2,4-L, or 

Amitrol in 25 quaits of water.' In June the full amount of spray was 

used in each plot,. but in AugUst the same mixtures were applied only s. 

in amounts sutti~~ent tor t~orough wetting ot livin~ foliage. Marylahtl 

plots were treated on June~7-20, and again on hUgust 26-27. 

. '... New Jet-saY plots reoeived similei' treatments I except that in 

the burrledbloo~~ no mixtures involving 25 quarts of water per plot, 

were used. Spr~tihg there was done on June ~~ or 27, and again on 

Au~st 2('>. ' , 

{, " 

1958 \lork 

Because ot the regrowth,of honeysuokle, three ot the 1957 ~locks 

were set tip for ~e-treatment in June 1958 and in June of the foliowing 

years until all 

unburned blocks 

honeysuckle had died. 

in New Jersey and the 

These three blocks were the two 

block ot silver maple and box- 

• t, elder at Loch Raven. Spray mixtures used were the same as in the 

original treatments, and.amounts used were sufficient for thorough 

wetting of living'honeysuokle foliage. However, because the effect 

of 

in 

1957 Amitrol 

these blocks 

treatments.eemed 

were not re-treated 

to be continuing, 

in 1958. 

the Amitrol plots 

, " 

Again because ot regrowth, some additional data to'determine 

its importance seemed desirable. Thus, 15 shoots were selected in 

June 1958, and staked for growth measurements. All 15 shoots were in 

plots not scheduled for subsequent re-treatments. 

1958 PLOTS 

Additional plots were established in 19~8, for two reasons. 

First, the,1957 drought might have affected results in that year • 

.. ! Second, June and June treatments, a year apart, might be more effective 

than June and August treatments in the same year. 

:t.', 

,'! '~ 

The 1958 plots included 4 blocks of 8 plots. These plots too 

were 1/40 acre in size. Each block included the,same number of controls, 

and the same spray mixtures on treated plots, as in the 1957 

8-plot blocks. Two blocks were in the Belleplain State Forest, N.J.; 

orie was ",in a light cover ot honeysuckle, one in a medium cover. The 

other two blocks were in Maryland's Loch Raven Watershed; one had a 

heavy cover of honeysuckle in the stand of silver maple anq· boxelder

363 

On 1/160-acre plc.ts in .the Be11eplain stand, the use of kerosene 

as a carrier for 2,4-Dand ACP-977 was also tried. Treatmentshere 

involved (1) only kerosene, (2) ACP-977 in kerosene (125 gallons per 

aero), (3) 2,4-D in kerosene, and (4 and 5) ACP-917 or 2,4-D in a 

catrier composed in half of water and in half of kerosene. 

RmSULTSANDDISCUaSION 

BURNINGJ.NDQRA2.1NG 

J. light fire, as used at Groen Bank, had relatively little effect 

on light and medium covers of honeysuckle. Because the Green Bank fire 

burned only deep enough to consume the L-layer and part of the F-layer 

of the forest floor, the honeysuckle sprouted vigorously. In late 

June 1957, less than 4 months after the burn, the unsprayed burned plot 

that had a light cover before burning was rated the same. The unsprayed 

plot that had a medium cover before burning took longer to regain this 

cover--to the end of the second or 1958 growing season. 

~n intense, relatively deep-burning wildfire, such as occurred 

on the Loch Raven Watershed in 1957, is more effective in eliminating 

honeysuckle than a prescribed burn. However, since it kills overstory 

vegetation, the honeysuckle that survives is very vigorous. By 

the end of the second growing season, surviving shoots in unsprayed 

plots of the Loch Raven burn had built up a cover similar to that 

present before-the fire. 

Grazing also reduces the honeysuckle cover, but apparently 

neither this nor ·fire is of much value in eliminating the honeysuckle 

problem. 

Effect of Cover Density 

SPRAYING 

The cover in honeysuckle-infested spots varies greatly in 

density, but the author doubts that variations between light and 

dense covers have much effect on the amount of spray necessary. 

in very dense covers most of the honeysuckle foliage is near the 

face and is readily covered. 

very 

Even 

sur- 

The spray treatments tried to date have had similar effects in 

waist-high growth as in somewhat scattered vines that formed light or 

very light covers. Since foliage sprays are used, and in practice 

might be applied by machine sprayers, nearly all densities of cover 

may need nearly the same amount of material. Hence, prior treatments, 

such as, burning or grazing, seem to have little value in reducing the 

amount of spray necessary.

364 

However, severing D£ high-climbing vines m~y ~sually be necessary 

'before spraying. 

Timing 

i~commendations by Brender and Hodges (3) on the timing of repeat 

treatments do not seem to fit Northeastern conditions. They 

recommend second treatments of #CF-~77 later in the same surr~er, of 

;.mitrol later in the summer or in the following spring. Under our 

growing conditions these se~mtoo soon. since areas treated with '~CI' 

977 may by then have had little regrowth, and the full effect of the 

initial Amitrol treatment may not have developed. So for Northeastern 

conditions a second treatment with ~CP-977 should probably be made a 

year atter the first. one; wi,th ,1Imit~l, 1 or 2 years after the first one. 

Type of 

Carrier 

,. 

:Vater seems preferable to oil as a carrier. At least there is 

n«i~dication to date that the use,of,oil, either alone or in mixtur.e 

with water, i~~ more effectiv~,carrier :than water. 

Amount of Carrier 

Desirable amounts of c~rrier seem to vary, although the differences 

are relatively sl~gh:t and do..not agree with recommendations 

by SoutheasternStation.pers9n~~~! Though they hav~.recoDllilended about 

250 gallons per acre as the carrier,.~or. J~CI'-977 (!, ~)., our results 

show consistently that the slUll~;amoun~; of ACI'-977 is.slightly 

fective when applied in 125 gallons of water per acre. 

more ef 

'. "'. ",'1' :'. 

In contrast, there is no

On the basis of their growth, and of the recovery of honeysuckle 

cover in plots treated with AC~-977 or 2,4-D only in 1957, the 

logical objective in preparing sites for tree reproduction would be 

elimination of honeysuckle, not partial control. The author estimates 

that tree reproduction may need a lO-year period for establishment 

and growth before it is beyond appreciable damage by this vine. If 

so, the scattered springs .till living in the best of our treated 

365 

burned, another growing season will usually be needed to permit the 

cover to reach its original density in the ACP-977 and 2,4-D plots. 

Of course, where a third treatment with these chemicals ~a~ 

made in June 1958, there is as yet little new growth. On first ' 

glance, these plots appear almost devoid of honeysuckle. However, 

close inspection shows a few living sprigs, usually 3 to 15 per plot, 

although in one plot none were noted. Just how important these will 

be, and how many treatments will be necessary to eliminate honeysuckle 

with these chemicals, are still unanswered question. 

Amitrol plots that were scheduled for another treatment were 

not given it in June 1958 because there was little living growth--and 

most of that was chlorotic. Whether the delayed effects of Amitrol 

will be sufficient to eliminate honeysuckle without additional treatment 

is very questionable. In September 1958 new honeysuckle shoots 

with normal foliage were seen developing in these plots. 

A?

366 

COSTS 

Since none of the treatments have been effective as yet, their 

costs are rather immaterial. However, none of the treatments tried 

has been cheap. For exampl'e, chemicals used in the 19~7 treatments 

would cost $10 to $14 an acre for 2,4-D, $24 to $40 for 1l.CF-977, and 

$24 to $34 for Amitrol 

Perhaps one saving feature is that costs per tract would usually 

be far less, because in most sect·ions honeysuckle occurs in spots, not 

throughout Whole. tracts. 

CONCLUSIONS 

The three principal chemii:als tried in our tests--Amitrol, 

2,4-D, and the combination of 2,4-D and 2j4,~-T known as ACP-977--all 

greatly reduce the honeysuckle cover, but the reductions tend to be 

temporary. On none of the plots, even those treated 2 or 3 times, 

have we as yet eliminated honeysuckle. 

Foresters need a treatment that, applied preferably only once, 

will eliminate honeysuckle vines at a reasonable cost, say $25 or less 

per acre. On that basis none of our trials can as yet be called successful. 

de will welcome any suggestions on materials or techniques 

that offer possibilities of meeting that goal. 

LITERATURECITED 

1 • 1l.nonymous. 

19~8. Getting rid of honeysuckle. Agr. Res. 7 (3)1 14. 

2. Bond, A. R. 

1956. Maryland's fifth column. ~er. Forests 62 (10): 46-47, 

88-90. 

3. Brender, E. V., and Hodges, C. S. 

1957. Honeysuckle or trees? U.S. Forest Servo Southeast. 

Forest Expt. Sta., Res. Note 103. 2 pp. 

4. Walker, L. C. 

1956. Controlling undesirable hardwoods. Ga. Forest Res. 

Council Rpt.3. 24 pp.

367 

A ProGRESS 'lEPORTON S n~z INP.FO~ a,t-rr11DLLING 

W~;'~DS IN ~'OPFJST & NU'"'SE.RYPLi\NTINGS 

. By 

E.dwinO. Sohneider (1 

Simnzino (2-ohloro-4,6-bis(ethylnmino)-s-tri&zine) wos 

introduoed experimentally to experiment station and other workers 

in 1956. Outstanding performnnoe as a pre-emergenoe weed oontrol 

chemi cn I in 00 III was reported in 1956 and aguin in 1957. Wood 

oontrol in other agronomio and hortioulture orops appear promising. 

Besides the agronomio orops, weod. oontrol in woody speoius and 

aque td cs were investigated. 1'1ios and Watson (4) reported 2 and 4 Ibs , 

per co re effeotively oontrolled weods for. tho entire season without 

oausing any injury to Taxus media hioksi, Cotoneaster aoutifolia, 

To.xus ouspidata o.nd Syrfngarotii"fnagen8Is.-'l:le-rronT!)'-o.ppTfed'i' 

2-ff:: banif07l)imnzine-~4 ilnd -8~por acr e to niJWly tro.nsplanted 

3 YGfH' old sugar mnple liners for weed oontrol on M'lroh 12, 1957. 

Weed oontrol wus exoellent wi th no injury for the season. Walker (5) 

in 1957 roported a 10% aotive ingrodient pellet showod promise o.s a 

herbioi'de for oontrolling aquatio sp'3oies of weeds without injury 

to several speoiosof fis:) or fish food organisms at soil sterili- 

. zation conount rvb Lons , Following tho label cccoptunco for oorn 

by the United states Depo.rtment of Agrioulture on April 19, 1958, 

o.nother LaboL was uco epbo d for weed oontrol in speoifio ornamonto.ls. 

This puper will deal wit h weod oontro 1 in forest and ornnmuntul 

tree plqntings and in other oonservation uses of Simnzine. 

TOXI01LQGICALPROPErTIES 

The acube oral toxioity of Simazine haa bo'.l!l determined in 

both ruts and mi.oe und was found to have an L1)50 in exoos s of 

5g/Kg. No irritr.tion to skin, oyes or muoous inombro.nes has bosn 

reported in ovor two yocirs of field and laboretory testihg. 

Simuzino is c white, orystallinJ substo.noo whioh hns a 

solubility of 5 ppm in water, 400 ppm in mothyl o.lohol, 2.0 ppm 

in petroleum ether rmd 900 ppm in ohloroform. Tho puro ohemioel 

has 0. 1W1ting point of 226 0 C. The 50% oommeroJ.n.l wettr,ble powder 

is whitish in oolor, virtually ordorluss and has extI'€JJn(,ly low 

toxioity to mo.n and animal. 

(l Geigy .tIgrioulturc.l Chomioals, Division of Goigy Chemioal Corp.

368 

Tusts huv

369 

PERFO~ANCE 

Simuzine hus been used in many tusts by oxporimunt station 

r·,s,; roh wor kc r a and oonsorv'.'tion personnel for oontrol of woods 

in corn (oonsorv[.tion uso) and in forost and ornamvntnl troe 

pl'lntings. DUel to tho m~ny faotors involvod, onch of tho above 

usos wi 11 be disoussed individu"Uy. 

Consorvation usc in growing corn - Corn for usa o s wilo 

lif8 fOc;ij-potohesuiiitnlfyhfs' p"lsnto-cCin ino.ooossi bLe a rons , 

'IN',S who·" oultiv·.tion is diffioul tor orons whf: l"L tho weod 

popuL:tion is v·Jry hi gh , Bo.yor cn d Buohholtz (1) found Simazine 

"ffaotive for qU£lokgrass and e nnua L wend oontrol wh-m upplioations 

we 'oJ mad" 3 woaks prior to pkntinl'; co rn in sod cul.burc , Th"y 

reported v0ry slow quaokgrass Gontrol whioh ooused stunting of 

tih s oorn from oompotition teforo thCl quookgrnss was killed. Th' 

oorn made 0. good reoovory and produoed 0 modorote yield. The 

onnuo I weods woro oontrolled for the so&son. nates used wore 

4 end 8 Ib s , lloti-vv per c cr-o e s cr. OVbra.ll hpplioation. 

ANo,s tillod prior 10 plunting ruther than plr,nting in sod 

usunlly roquires loss of th

37) 

Th" 'Hlplior..tion gave oxo oLl.onf oontro 1 of 

no rrn-il oost of hand weeding was from ~200 

Culti V"tion was us od prior to applioation 

compc cbd on; 

thus" '¥~ods whGru th.) 

to ':300 per no ro , 

to reliovo soil 

DonUyl (2) used 2 and 4 Lbs , Simo.zino in 0. 2 ft. bo.nd 

over nowly planted lX Sootoh Pine treos in an abandoned fiuld. 

Th,; troos war') p lr n tud in April whon tho gro.sses wor-e just 

sto.rting to 'Jmorgo. The o.pplication controlled tho vegot!1tion 

thnt would compcbo for moisturo or would smother thu amol.l, 

troe during tho winter when snow po.oks the dead vngetation do,~. 

Applioctions of Si~Qzin~ o.t 2, 4 and 6 Ibs. per r.ore on 

newly plr ntud Sootch Pino in the spring of 1968 in Hissouri gavo 

fair control at 2 lbs. por o.ore o.nd oxoellont oontrol of annual 

weeds rmd grassEs at tho 6 lb. por ao r e ruto. Those treatments 

o.l1owod obhor low growing woody speoies to nfford shndo and 

pro taotion duri.ng tho summer. SC1otoh Pin') o.nd other ncr-row Loaf 

or-namcntinLs in a nursery for replr.nting on Ohio ror.ds were kopt 

fr-;o of interfering weeds when applioation at 3 Ib s , pur c or o 

was madu in 0. 2 ft. b~nd over the row in early May. Roduotion 

of competition from woeds rosulted in additiono.l growth of the 

trr:f,s. Simr,zine at 3 Ib s , per aor-e o.pplied on april 28, 1958, 

in a wood infestod urea improved the survivlll of tho lI'/hito Pinos 

in 0. very dry year by eliminating oompetition. NonQ of tho treos 

sur vi vod in tho untronted ur ou wher-eas 66% wor o living on 

Soptembnr 17, 1968, in the tro~ted o.ren. 

SUMMARY 

Simazine h:ls been us ed for the c on tr'o I of annun L wo.sds and 

gr'lss:iS in corn pInrrt e d in sad oulture or with minimum tillage 

in r emot o loc",tions fo r bird food. In quo.okgrnss infestod ur-en s 

tho rota must be incroasod from 3 lbs. to 6 to 6 lbs. por acre 

for oontrol. 

Most ~ody speoios of plants smw rusist!:.noe to Simazine 

wh,m USGd for weed oontrol either as a dirooted or ov orn l L 

spray for pre-omergenoe weed oontrol. Many speoies show 

toleranoe. However, only Applo (non-bonring), Balsum Fir, 

Burber ry , Boxwood, Cotonuaster, Douglas Fir, Frnser ~'ir, Juniper, 

Norway Spruoo, Privet, Rod Pine, Red Spruoe, Roso, Sootoh Pine, 

White Pino, Yow (Tnxus) ",nd 1Vhite Spruoe aro oloared for use.at 

the presunt tim,l. AdditionEll spco Ie s of forost tr.;os nnd 

nursery p1E.nting will bo added as do.tn is roocivod on tolorano

371 

Litaratur~ 

Citod 

(1) 

(2) 

(3) 

BnyJr, n. E. und Buoholtz, K. P. Tho use of Horbioidos 

for tho Produotion of Corn in Sod CultuN, (abstraots), 

"ToJd Socivty of Amerioa pp.l '1958 

Don,Uyl,D. Purdu~ University, Lafayetto, Indiana 

Per acne I Communi~.tion 1958 

Horron, J. W. Control of Woods in bods of Taxus modia 

hioksi and Sugar Maple Plantings. Rosoaroh Roport 

North Control Wood Control Conf. 14:146 1957 

(4) Ries, S. K. and Watson, D. P. W(jed Control in lining-out 

stook of Four Speoies of Ornamontnls (libstraet) 

North Control Wood Control Conf , 14: 49-50 1957 

(5) Wfllker, C.~. Results of Somo Exporiments in thu Control 

of Certain Aquatic Weeds in Misouri Ferro Ponds (Abstract) 

Pro o , North Contra 1 Woed Control Conf. 14: 30-:n 1957

The repeated cuttinG of the vee;etation t'lith hand tools,or by 

mo",ho.,.".Jj"o.1 r'''''~oY\a "y'hlCltoY'O ~nY"\'{"'!:IIh'~ hoc:! ~"'OOYl r.ho .Rr",...o'n+_~n r.1~t:ht"u·~ 

372 

"l'he Use of )cn~])icides in Nature Sanctuary ;lanacement' 

2u;.)ene Decker, Resident Director 

1.'estraloreland sanctuary 

r:lount Kisco,New York 

As our ur-ban areas lTith their spral1line; sueur-be continue to 

;rOl1 Ilith our explodinp; population, the necessity of setting aside 

na tural tracts ,'rithin them is becoming more evident and popular. 

f', discussion of the need for and purposes of these natural areas 

has been the subject of many publications, and I am sure that an 

of us are aympat.het f c with the movement. These "open s pacea' 

Iii thin the populated sections may take the form of par-ks , sanctuaries, 

natu.re preserves, \'!ildlife refuees, or other similar operations. 

The terrn"nature sanctuary" as used in this paper refers to 

t r-oae tracts uhich are retained in a natural state and are also 

ut Ll Lzed for nature study and conservation educat.Lon activities. 

'1.'hese acti vi ties [~enerally consist of tours alone; trails trhf.ch 

lead through the various communities uhere the relationships or 

tr-e plant and animal life are explained by e;uldes, siens, or ~~tl1c1.e 

uoolca , 

The purpose of this paper- is to describe the usef'ul.neas of 

cheru ca I herlJicides as tools in the manac;ement of nature sanctuaries. 

I'BED AjTDrillQUIIilll\1EHTSOr. FEIIDICIDES. 

Since the operation of a nature sanctuary is centered around 

its use by the public, the maintenance of the trails \'!1thin the 

area is a major concern. These paths wind through various C01l1 

num.t.Lea and shouldiJe leept as natural 1001

373 

involves many manhours of labor and upkeep of equipment during a 

period of increased activity on the sanctuary. The resulting 

trails often tend to be artificial in appearance with the fresh 

cut stumps and sprouts. 

The development of chemical herbicides has provided promising 

tools for the management of these trails. The simplicity of 

the equipment involved and the labor-oaving factors of their use 

are both favorable considerations for their adoption. The herbicides 

also appear useful in other sanctuary management operations 

such as the elimination of grass from parking areas and drives, 

and the initial clearance of new trails. 

The requirements of herbicides for use in nature sanctuary 

management are probably more restrictive than those for other 

operations. First, the materials must be non-toxic not only to 

the public but also to any wildlife which may come in contact 

with the treated vegetation. The volatility of the herbicide 

must be low in order to safeguard desirable growth near the 

sprayed sections. Other considerations are the selectivity of 

the herbicide to species involved in the various operations, and 

the ease of application. 

HERBICIDESUSED. 

Chemical herbicides were tested on Westmoreland Sanctuary, 

Westchester County, New York, during the spring and summer of 

1958. This project was conducted with the cooperation of the 

Agricultural Chemicals Division of The Dow Chemical Company, 

which supplied the chemicals tested. 

Four materials commonly referred to as systemic hormone type 

herbicides were used. They are various formulations of 2,4-D, 

2,4,5-T, and similar materials. The commercial formulations used 

are known as Veon 245, Garlon, Kuron, and Baron. 

Trade Name and Active Ingredients 

(CommonName) 

Veon 245 Triethylamine salt of 2,4:r5-trichloro- . 

(Amine salt of phenoxyactic acid, minimum-----------------56.7% 

2,4,5-T) 

Garlon 

Diet~ylene glycol bis, 2,2-dlchloropropric~ate, 

minimum--------------------------50.8% 

(Dalapon ester 

plus low volatile 

ester of propy..L2M glycol(C'1H60 to C H 00 ) butyl 

2- (2, '+,5- t!'ichlorophenoxy )propionic a cLd, 

silvex) 

eth8r esters, minlmum-----2-l~-3---------~- 7.7% 

Kuron 

2-(2,4,5-trichloroph~noxy)propionic acid,' 

(Low volatile propylene glycol(C3Hh9 to C HI ° ) 

ester of silvex) 

2-(2,4,5-trichlorophenoxy)propionic aCid, 

butyl ether esters, ~in1mum2--a_3 64.5% 

equivalent, minimum------------------------35.5% 

Baron 

2-(2,4,5-trichlorophenoxy) ethyl 2,2-dichloropropionate---------------------------30.5% 

(erbon) 

Related compounds--------------------------]().8%

374 

Recommended I'lixtures 

Veon 245 

Garlo" 

Kuron 

Baron 

Used: 

- 1 part Veon 245 to 100 parts water. 

- 1 part Garlon to 30 parts water. 

- 1 part Kuron to 100 parts water. 

- 1 part Daron to 6 parts v~ter. 

These materials were chosen as they have been proven non-toxic to 

man and animals in the dosages recommended for application. The 

toxicity of the materials involved h!Ve been a~equatelY tested 

and discussed ty Gl'igsby and Farwell • t!illard , Fertig3, and 

Rmle and Hymas. The Vlestmoreland sanctuary has a high population 

of Hild 1Jirds, mammals, and reptiles, and no evidence of 

any adverse effects on any form ~'18.s noticed even though the treated 

areas t'1ere round on all communities. 

These sprays Here also selected because of their lOll volatility 

and no damage to adjacent vegetation Has observed after 

their use. Tbe dan2;er of wind drift was eliminated by controlling 

the droplet size of spray rJy adjusting the nozzle. 

The materials chosen all form mixtures readily with Hater 

Hh:i.ch greatly facilitates their use in the field. A three-gallon 

~)ooster tank and pump Hith a back sling \'las used for all spraying 

treatments and proved to ue quite efficient. 

Fi~ures for the amount of spray needed for a definite length 

of trail to be treated are difficult to calculate as the application 

varies according to the density of the species sprayed in 

the various communities. 

IIJ\IHTENANCEOF TRAILS. 

A. ,:ooded Communities. Hoody vegetation in the paths can be adequately 

controlled with the application of a suitable herbicide 

in late spring. ~aple-leaf vi0urnum was a major problem 

in these trails and it was easily controlled by application 

of Veon 245 spray. Other growth in the paths l{illed by 

this spray Here spice bush, red maple, floHerinc; dO(;1.'IOOd, 

White oak, chestnut oak, and Virginia creeper. lIhite ash 

t'~s found to be particularly resistant to this spray. The 

vegetation in the paths is especially Vigorous and gersistent 

as it was mostly sprout gr-ovrth resulting from the initial 

clearance 1:Jycutting. One spraying t'~s successful in eliminating 

the woody gr-ovrcb and only a folloll-up of spot spraying 

for later c;rm-lth t'laS necessary. The killed vegetation 

dried out rapidly, was easily Imocked dOt'm, and the resulting 

path "as quite natural looking.

375 

Poison ivy was completely eradicated alone; the ede;e of the 

trails HHh Veon spray. This spr-ay wae applied so as to,' 

pr-ov ide a lane t hr-ough the large patches so that users of 

the trails would not corne in contact ~'lith it. No attempt 

was made to completely eradicate these communities as they 

ha\e a definite influence on keepin('; the sanctuary visitors 

from \'Ianderlng away from the trails. Also. the po Lson iVy' 

fruits produced in these patches are \'ridely used for food 'q 

~'ri1cl :;irds. ' , 

Open Communities. Grasses and broad-leafed Heeds present 

pro',Jlems in the trails tihrough the old fields and throuGh 

opendrigs in the vroodj.anda , The application of Oar Ion spr'ay 

to these trails provided cessation of gro\'lth and an open 

clear trail. 

C. Initial Clearance of Trails. The development of a nature 

sanctuary necessitates the location and clearance of trails. 

Once the heavy material has ~)een removed, the s:9ra~rinG of a 

brush lcil1er on the remaininG gr

376 

i1eferences. 

1 Cric;sby, B.H., and1't'arlfe11, E.D.: Some effects of Herbicides on 

Pasture and on GrazinG Livestock, l'tlchi~n J\e;ricultural Experiment 

Station 0.uarterly Bulletin, 32, (1950): 37[1-3:35. 

2 Hillard, C.J.: The Status of Perb1cidal POisoning. Proc. Eighth 

Annt~l ~~etinG~ North Central Weed Control Conference, (1951): 

3~-09. . . 

.J 17ertiG, S.N.: Herbicidal Poisoning of Livestock. Supple Proc. 

Seventh Anm,18.1f1eeting, Northeast \leed Control. Conference (1953): 

J~lj· .. 47 • 

J~ 

HOl,re, V.K., and Hymas, T.A. :Sul1llllary of Toxicological Information 

on 2,4-D and 2,4,5-T Type 1~rb1cides and an Evaluation of the 

Hazards to Livestoc!< Asa.oc1ated \'lith the1rUse, American JOUl'· 

nal Ve-ter1,na.ry Re&eaI'Oh, Vol. xv , No. 57, Ooto.l>er 1954: 622-629.

377. 

WEEDCONTROLON GLADIOLL'S1958 RESUL'lS 

Arthur 

Bing 

Cornell Ornamentals Research LaboratoI7 

Introduction 

:S"udies on weed control for gladiolus cormel plantings have been 

carried on at the Cornell Ornamentals Rl'lsearch Laboratory on Long ErLand 

for several "ears (1) and on flowering stock at other station. (2,3). 

This report covers the 1958 results on Long Island. 

:!2:~ 

The cormels were planted on May 20. There were 11 rows and each row 

contained 20 lots of lOCO cormels, 10 lots of the variety Friendship 

alternating with 10 lots of the varietjr June Bells. Each lot of 1000 

was planted 2 inches deep in a space ~ inches x 4 feet with 1 foot of 

blank row between varieties and 2 feet bet~Teen treatment",. The rows l-rere 

36 inches apart center to center. A treatment consisted of one lot of each 

of the two varieties. There vlere 22 treatments replicated five times 'with 

the {irst t1.rOtreatments in each row block A, the 'second Block B I etc. 

All treatments were replicated once in each block." Cormels were covered 

with a hill of soil "hich was raked level on June:3. The field was irrigated 

June 5. Granular treatments with S1ma.zin, Diuron, and Chloro IPC were 

applied with a fertilizer srreader on June 6. Int~rmittent sh~.rers held 

up further applications until June 11 .Then the remaining treatments were 

applied. 

Results 


1-leed growth in the plots 1.TaSrated on July 11 by' two observers. 

Results are shown in Table I. Nutgrass was quite prevalent in most plots 

and as no materials showed control it is not included in the ratings. 

j~fter rating all plots were weeded. Values in the the table were on 

the basis of 0 for no weed gror,Tth to 5 tor full of weeds. The best 

weed c011trol was from 4%CIPC-W' SES granular 

Soli/A,Diur

378 

of yields showed no significant differences bet1,reen treat11l3nts. 1Tariety 

Frtendsh1p grEl"Ywell and Table II ShOlol"S the yield data. All treated plots 

had an averap:e ,r1e1d bi~her than all the untre,.tedexcept G3OO31which 

was also very 10t0T ~rieldin\< 1'1 variet~r June Balls. No treatments were 

significantl', hannfu1 to the yield of variety Frie'1dshlp. Actua1l;v' 

Bevera1 treahe'1ts yielded ili'r'1i.fiOF.n,t13rh·.'her than the untreated. The 

lower ,rield of untreated plots is due to the weed oanpetition before 

rating and subsequent weeding of the weedy plots. tater regrmfth of 

weeds after the weeding was probably not so ser tous to 'the crop. 

On the basis of ere» yield, the best treat'rents wOl'ld be rated 

roughly in the follOl.r..nr; order. Karmex W1 1/2#, Neb"ron fill, CIPC ell, 

CIl'O 6%-5ES'4% loci1,CIR: 4%-SES4%at 15a;, Karmex IXY1 1/2tr, Silnaz:1n 

2# granular, Diuron 2f,! granular, 1'ollowed ~r :nost of t 11e other treatments o 

Good weed control makes it much easier to dig the younr: corms. Crabgrass 

is the most difficult to co~tend with when dig~ng. 

S'llIIIlIIar;r 

Many treatments gave ~ood weed co,1trol B.11dproduced crop 

yields greater than from the untreated plots. On the basis of crop 

yield and weed control the following treatments per1'ormed best, 

Karmex W 1 1/2#, Neburon 6#, Kal'llflX 

IXY1 1/2#,crro 1S-sES4%at 

150 lbs ~nu1ar, CIPC PI!liquid, CIro 6%-5ESI.l%100 Ibs granular am 

Diuron 2%granular at 100 1bs. 

Acknowledgment 

Cormels for this exreriment were sup"'Ued by" "The House of Spic 

and Span", Newfie ld, N81.Jersey. 

ReferenMl!' 

1. Bing, A. 1956 Gladiolus Weed Control Exr-eriment. The Gladiolus 

i1: 207-211. 1957. " 

2. Butterfield, N. W. and E. C. Gasiorkiewicz, Chemical "leed Control 

of Glad:\."llus. Mass. Flower Gror·rers ,~ss In. Bul. 40: 5-6 

March 1957. - 

3. Gasiorkiewicz, E. C. Comparism of Granular and Liquid Applications 

of Herbicides in Gladiolu8, Northeastern T'1eedControl Conference 

121 119-121, 1953.

379 

Table 

I 

Weed Growth 

*(Scale 0-,) 

Tree:.tment June 6 CJ!' 11 

Untrea ted if1 

Untreated #2 

Untreated #3 

SOO zin ]fr Gran 

S:iJnazin2# 

Gran 

S:iJnazin 3# Gran 

Simazin ]jf 1iq . 

Simazin '2#LX 

Kamex !IN 1 1 2# Liq 

Karmex W 1 1 2 # Liq 

Karme:x:Diuron J# Gran 

Karmex Diuron 2#Gran 

Neburon 6# Liq 

CIPC 8# Gran 

CIPC 8,1Liq 

G300312# Liq 

Sesone '4#Liq 

** C6S4 ,ri!Gran 

** C6S4 100 Gran 

** C6SL.1~ # Gran 

***C4S4100 # Gran 

***04S41,0 # Gran 

Block 

Weed Gr01rt.h J~r 11 

A B C D E Average 

,. " 

, 

1., , 4., S " 40 2 

s ," , S· 

4 

, 4., 4 " 

4., .4~4 

:3 3 2 1~, :3 2;, 

4 .3 2., 2", 2' 2..8" 

1 0 2" 1., 2., 1;4 

1 0 o~, 1 1 00 7 

0 1 O..S 0 1 0., 

1 1 0 O.S 0 0., 

1 2.., 1 0 1., 1~2 

1 0 O.S 0 1 0., 

1 0 1 0 0., O~, 

3 

, 1., 1., .3 2.8 

0 1 1 1~, 2., 1.2 

2.5 I 2 1", 2 , 0 1.9 

1.5 1 2 2 .3 1.9 

.3 2 4 2 2.., 2~7 

1 2 .1 1., 2 1~, 

1 1 1" 0 0 0.6 

, 1 1., 1 0 1~7 

0 0 1 1 0 0.4 

Required Significant Difference between averages 1.1 

* Scale 0 

1 

No weeds 

1Tery few weeds 

2 Few weeds 

.3 Some weeds 

4 Ha'lY weeds 

, VeIY weedy' 

** Chl0r0!PC 6%-Sesone 4%granular at '!I>#/Acre 

*** Chloro I1'C 4%-Sesone 11%granular 100#/Acre

380 

Table II 

~.., 

Treat1nent June 6 or 11 

Gladiolus CormYield Variety Friendship 

(From1000 oormels) 

Yields in Grams 

A B' 0 D E AVBrage 

Untreated #1 720 680 1130 680 730 798 

Untreated #2 930 490 890 690 1130 826 

Untreated f,~3 980 700 1700 650 1180 10tl2 

Simazin 1"1Gran 860 910 930 1050 710 872 

'3imazin 2 f. Gran 980 1290 1650 1430 1030 1276 

Simazin 3 if Gran 990 850 1340 1350 1230 1152 

Simaztn 1 If Liq 1050 1320 730 1130 1240 1.094 

Simazin 2 {,~ Liq 880. 1150 1040 1030 1510 1122 

KarmexIJ.:11 ,%2 ;:1 Liq 1210 1220 1750 1330 880 1278 

KarmexT'11 1 2 Ii Liq 1090 1010 1540 1610 1350 1320 

Karr.lexDiuron 1 # Gran 1020 840 1110 1200 1120 10,8 

KarmexDiuron 2 .J! Gran 1310 980 1430 1510 1100 1266 

Nebm>on6 # Liq 860 1290 1300 1490 1560 1300 

C!FC 8;~ Gran 1040 730 1300 1490 1430 1198 

CIPC8 # Liq 1070 1400 1340 1630 1000 1288 

G 30021 2 If Liq 980 1170 870 700 910 926 

Sesone 4 # Liq 830 1160 1280 920 920 1022 

** C~4 ,0 # Gran 930 1400 1000 1440 930 1140 

*l~ Ce 4 100 # Gran 1290 950 1430 1530 1220 1284 

,f* C6S~ 1,0 # Gran 1010 910 1060 16eo J3$0 1186 

*If* Ctl4 100 f,~ Gran 730 1180 1160 1300 1510 1176 

:Hf* C434 1,0 # Gran 1360 1000 1300 1420 1260 1288 

" ** 

*** 

~equired ~ignificant Differe~ce between averages 222 

Chloro IPC 6%-Sesone~ granular at 5cij{Acre 

Chloro IPC 4%'3esone 4,'1;granular 100 # Acre

Evaluation of DNBPand Sesone for 

Control of Weeds in Gladiolus 

L. L. Danielson and Neil W. Stuart- 

Abstract- 

2/ 

1/ 

Weed control investigatianliJ in gladiolus under field cond itions were 

initiated in 1957 and continued through 1958 to obtain data on the effect 

of DNBP(4,6-dinitro ortho secondary butylphenol) am sesone (sodium 2,4-dichlorophenaxyethyl 

sulfate) on yield and qUality of fiollers and corms of 

gladiolus and on date of flollering. 

Pre-emergence applications of 6 pounds of DNBPper acre were used 

alone and in combination with pre- and post-flowering applications of 

3, 4, and 5 pounds of sesone per acre. Plots were irrigated before each 

application. 

Corms were weighed and counted at planting and digging time. Corms 

treated in 1957 ware stared and planted again in 1958 to study the possibility 

of carry-over of herbicidal effects from season-to-season in the 

corms, Total length of each flo'Wer stalk and the length of its flowering 

portion were measured. Numbers of flower stalks, florets per stalk, side 

shoots per stalk and date of opening of first floret on each stalk were 

recorded. Treated plots were compared with hand-weeded plots. 

Annual grasses and broadleaved weeds war e con trolled for the entire 

growing period with a l1'e-emergEnC8 applicaticn of DNBPfoUolled by preand 

post-flowering awlications of 3 pounds of sesone per acre. 

None of the treatments had any effects on flowering or corm production, 

and there was no evidence of carry-over effect, when using single 

applications. There were indications of injury from double applications 

of sesone at the higher rates. 

1/ Plant Physiologists, Crops Research Division, Agr1.cultural Research 

Service, U. S. Department of Agriculture, Beltsville, Maryland. 

y Paper to be offered for plblicatian in the Journal of the Weed Society 

of America.

1~E;'\ 

C(WTRO:r.. FOR:PEC'NYPL

Table I 

1ieed Control 

on Peonies 

.tl::.~e.!:~l Il!t,! ia..=t~y~'- ]~a~i.2.n_o! ,£O!!t!:0t: ~_ 

Karmex IJo1 2#/loo gal Clean unt1.l time of fl~rer cutting 

Karmex IJo1 '4#/100gal Clean until al'tUl1ll'1 

Karmex Diuron 1%granular ?iI Clean until. time of flOl·rering 

Kar'1lElxDiuron 2%granular L# Clea.n until &"tumn 

GIro 8#/i00 gal Poor control by spring 

CIrc 5%granular 8# Poor control ~r spring 

U..t..reated 1'1ee

Gr~nular Mylone -- A Preplanting Measure for Control 

of Perennial Weeds of Nursery and Ornamental Plantings 

A. M. S. Pridham, Cornell University 

Screening tests to determine the effectiveness of granular Mylone formulations 

at several rates and temperatures was ~one in the greenhouse. Unsterilized 

soil units of 1 pound at approximately 30i moisture (iry weight 

basis) served as test units to which weed seed or root pieces of Artemisia 

vulgaris, Agropyron repens, Amaranthus retroflexus and Digitaria sanguinalis 

were used as test weeds. 

Thirty pounds of soil were spread on polyethylene sheeting and the appropriate 

amounts of Mylone added. It is assumed that 50il a furrow slice deep 

will weigh 2 million pounds per acre. Mylone was used at 300 pounds of 

active ingredient per acre. After table mixing, the sample was placed in a 

Leverpak drt~ and rolled for 5 minutes to complete the mixing of the Mylone 

with the soiL 

Culture samples of 1 pound were weighed out into polyethylene bags. Weed 

samples were added and the bags closed, labeled and stored for a week at 

selected controlled temperatures of 35°, 40°, 450, 500 and 60°F. 

Treated soils were then removed from storage and transferred to flower pack 

paper containers. Soil was firmed, moistened and the surface sown to redtop, 

Agrostis ~, grass seed carrying yarrow, Achillea millefolium, as an 

impurity. Soil samples were placed in a greenhouse at 50°F night temperature 

and 50-55 0 day temperature. Germination of seed and gro·wth of root 

parts w~s noted at intervals and records concluded after 6 weeks. 

The formaldehyde-like odor of Mylone was present in the storage chambers and 

faintly so in the greenhouse where the cultures were placed. Germination 

was normal in rate and amount in control cultures from all temperatures from 

35 0 to 60 0F. Mylone treatments of 30C pounds of active ingredient per acre 

were not detrimental to germination or growth of redtop, Agrostis ~, 

when treatment temperatures were 50 0F or more. Germination was usually 

slower where treatments were made at 35 0F or where amounts of Mylone exceeded 

300 pounds of active ingredient per acre. The weed count includes 

those weed seed added to the soil as well as those present in composted 

soil but excludes yarrow. Weed counts are given in Table 1. 

Under the conditions of this test, weeds were controlled as seed or seedlings 

when Mylone was used at 150 to 300 pounds of active Mylone per acre 

and where soil temperatures of 45°F or higher prevailed for 7 days following 

application of the Mylone. 

Artemisia vulgaris and quackgrass, Agropyron repens, failed to grow 

Vigorously in the controls and did not appear in any of the treatments. 

These weeds were gathered from below frost line in frozen &oil. A second 

series was set up later and treatment confined to the 30°F soil temperature.

'rable L The effect of Mylone on germination of weed seed sown in 

soil prior to treatment with Mylone. 

Total number of seedlings - 5 reps. All seedling weeds 

after 5 weeks. 

Temperat:lre 

.nadrrta fned 

during 7 day Pounds of active' 

treatment of Untreated 5C bran formula 

soil sample control ~OC 150 IL 

35 0 F 91 4 10 54 2 5 21 

40 104 0 10 5() 3 1;1 51 

45 112 2 2 35 0 4 7 

50 174 0 8 64 j 3 3 

60 .u: .2- .2- ~ 0 0 0 

557 11 35 235 8 31 82 

385 

Table 2. Number of shoots of Artemisia vulgaris from 20 stolons, 

5 each in 4 replicates following treatment with Mylone 

at 30 0 F, 7 days. 

Pounds of active Mylone/Acre 

Formulation 0 38 75 ~ 300 

Mylone 25;' 

bran 

8 9 6 0 0 

Mylone 10;. 

vermiculite 

11 5~ 4t 0 

These results confirm earlier ones of 1957 under field conditions with sandy 

loam at 40-45 0 F and where wettable powder formulation of Mylone was compared 

with Vapamfor elimination of Artemisia vulgaris. Present tests suggest 

that early spring treatments could be made successfully. 

In April 1958 treatments were made as soon as the soil was dry enough to 

rototill. Soil temperatures ranged from 40 to 42 0 F at 4" depth. 25;' bran 

formulation and year old 10;' vermiculite formulations were used. Half of 

each plot was covered by plastic; half remained open. No heavy rains fell 

during the perio~ ~t a week after treating. Whenthe plastic cover was removed, 

test Plantfewere made. Pe.cELs_~~ terminalis and Vinca ~ were 

planted and redtop grass seed was sown on the soil surface. 

Randomsamples of soil (1 square toot) were taken in November and the root,a 

of Artemisia sorted out, washed free of soil and air dried, then w~ighed. 

The results are given in Table 3.

386 

Table 3. Effectiveness of soil sterilization treatments with Mylone 

and with Vapamfor control of Artemisia vulgaris in sandy 

loam during early spring prior to planting out bare root 

nursery stock. Results in terms of grams of green weight 

of surviving stolons in 1 square foot soil samples taken 

at random in duplicate. Fall 1958, 6 months after treatment. 

Treatment 

and rate 

Date of treatment 

April 29 June 3 

Undisturbed soil 

Rototilled - untreated 

Rototilled Mylone 25%bran 

300 pounds Active/acre 

150 II II 

300 lbs. Acti velA, Vermiculite 

Rototilled Vapam 

82 grams 

63 98 grams 

o 0 

17 

5 

5 1.0 

Mylone and Vapamused at manufacturer's recommended rates drastically reduced 

the stand of Artemisia vulgaris in sandy loams. 

Plant survival in the potted ground cover materials ~~and Pachysandra 

is reduced if planting is dona 7 days after treatment but established Forsythia 

plants adjacent to treated plots did not show injury from treatment. 

Table 4. Survival of Pachysandra terminalis and of Vinca minor set as 

bare root plants in sandy soil 7 days after soil-rreatments 

were made. Soil 40-42 0F. Plot covered No cover 

7 days 14 days ~s 7 days 

30il treated with Pachysandra Pachysandra Vinca Pachysandra 

Mylone 25'!obran 

300 lbs. Active!A 100'/0 100'/0 100'!o 30'!o 

150 lbs. Active/A 80 100 100 70 

Mylone 10% vermiculite 

300 lbs. Acti velA 80 100 100 70 

Vapampt/lOO sq. ft. 0 100 100 40 

Untreated - rototilled 70 100 100 100

Effectiveness of granular Mylone treatment of silty clay during early siring 

Treatments were begun on May 12 as soon as t~e soil had dried s~fficiently to 

permit rototilling. In the first soil test, temperatures were 43-45 0F, plots 

were 100 sq. ft. in size and bordered on two sides by established plants of 

Forsythi-3. intermedia variety Spring Glory. Plots extended between the rows of 

Forsythia. One series was covered by black mulching polyethylene and another 

left uncovered. No heavy rains followed during the week. On May 1:;1the 

series was repeated but both replicates were covered. Heavy rains occurred. 

Tables 5 and 6 indicate the rates and treatments as well as the survival of 

test crops. 

Table 5. Survival of ~~planted at the conclusion of a 

7 day treatment with Mylone - no period for aeration. 

rate of Mylone 

treatment 300# aelA 150#ae/A 75#aelA Untreated Vapa.m 

and formul""tion B.R. Pot B.R. Pot B.R. Pot B.R. Pot B.R. Pot 

---- 

May 12 

25'%bran - open 4 4 4 4 4 4 4 4 

- covered 2 4 4 4 4 4 4 4 4 4 

May 19 

covered 

1010vermiculite 3 2 4 4 3 4 

3 4 

2510bran 1 4 4 4 

0 4 

13 14 24 16 8 8 II 12 4 4 

~ Ib ~ 10 S' S' 12 12 4" II 

Table 6. Survival of Pachysandra terminalis planted at the conclusion 

of'a 7 day soil treatment with Mylone - no period for aeration. 

Date of 

Mylone 

treatment 300# aelA 150# aelA .75# aelA Untreated Vapam 

ann formu:i.ation B.R. Pot B.R. Pot B.R. Pot B.R. Pot B.R. Pot 

---- 

b'Ai 12 

25 bran - open 1 4 3 4 4 4 4 4 

- covered 2 4 3 4 4 4 4 4 4 4 

May 1;1 

covered 

1010vermiculite 4 2 3 4 4 4 

1 3 4 4 

2510bran 0 1 2 2 

1 0 4 ..J. 

;I 

* 

19 21 8 8 12 12 4 4 

~ 21+ 21+ S' S' 12 12 4" 4"

388 

nther test plants 

Plant 

Euonyrnus fortunei coloratus 

Chrysanthemum morifolium vars. 

Rose Better Times 

Survival 

Control 

B.R. - 50% 100% 

Pot - 80% 100% 

B.R. -~ 100% 

Other treatments 

Granular Nemagon applied May 26 resulted in no mortality in Pachysandra, Rose 

Better Times, Chrysanthemum, Vinca minor, or Caryopteris. 

Mylone used at manufacturer's recommended rates resulted in reduced stand of 

bare rooted nursery stock set out in treated soil 7 days after treatment. 

Pachysandra, Euonyrnus and Rose were more susceptible to injury than was Vinca 

minor. Potted plants set out without disturbing the root ball survived ---- 

better than bare rooted plants of the same age and species. 

Re-establishment of weeds in sterilized plots 

Following treatment of soil with Mylone, the plastic cover was removed and 

soil walked on in the process of planting. This occurred twice once at the 

time of taking off the cover and the second time a week later. No hand weeding, 

hoeing or chemical weeding was done during the summer. 

In October weeds were cut off at the soil surface, sorted and weighed. Count 

was made of large weeds beyond seedling stage. The number of large weeds reflects 

the relative amount of hand weeding needed to keep the plots clean 

through the summer till early fall growth of seedling weeds. 

Untreated plots had Canada thistle, Cir'Gium arvense, Malva rotundifolia and 

~onchus arvensis as commonperennial weeds. Plots were:rree of Agropyron 

repens and Artemisia vulgaris. Pigweed, Amaranthus retroflexus, and lambs 

quarters, Chenopodium album, were commonas was groundsel, Senecio VUlgaris. 

Weeds of treated plots were mainly pigweed and some Canada thistle and later 

groundsel in quantity. 

Tables 7 and 8 indicate weed populations of treated plots in comparison to the 

untreated control in terms of number of large ,{eeds dnd total gram weight of 

weeds per plot. 

The use of a plastic cover in these tests leads to more effective weed control 

in terms of reduced number of weeds growing during early to mid-summer. This 

is especially true where manufacturer's rates were used though some reduction 

in weed population also occurred at lower rates. Reduction in total weight 

of weeds leads to similar observation and reaffirms the value of using adequate 

amounts of material as well as a plastic cover.

Acknowledgment is hereby given Carbon and Carbide Co. of NewYork City for 

Mylone wettable powder and to the Miller Chemical and Fertilizer Corp. of 

Baltimore, and the Vermiculite Corp. for formulations; also to the Stauffer 

('l"hom-t ....ol ("I" ("11-10'".·\",.0. ...,. 1\1 V .p,..._ 'tTa'l"\I':'IWI ,,

390 

PREwANDPOST-PLANTINGTREATMENTS FORWEEDCONTROL 

IN 

NURSERYLININGOUTSTOCK l 

By 

R. L. Ticknor, J. R. Havis, P. F. Bobula 

University of Massachu~etts, '~altham 

One of the most expensive weed control jobs in the nursery is 

in beds where plants are grown until large enough to be planted in 

the field. Because of the close spacing of the plants hand labor 

must be used to control weeds. 

A major hope to alleviate this situation is by the use of 

prewplanting herbicides. These materials usually control soil 

dissaaes and 80il insects as well as weeds. 

Previously we have reported on use of five materials as 

prewplanting treatments. The three most effective materials,w 

methyl bromide, DMIT, and SMOC• were used in the trials this year. 

In addition, pilot work was started this year with another material, 

EPTC. 

Since none of the plots remained free in previous years, postplantin~,treatm£nts 

were added to suppress weed growth. Mulches 

of bark and sugar cane 3 and granular CIPC were applied after the 

stock was planted. 

METHODS 

Each pre·planting treatment, applied on June 6th, was replicated 

three times in S' x 20' beds. Soil temperature was 660F. at treatment 

time. Methyl bromide was applied under a plastic cover at a rate of 

one pound per 100 equare feet. DMrT90 percent in pelleted form wae 

applied at 3/4 pound per 100 square feet and rotary tilled to a 

depth of five inches. SMDCwas applied with a ."hozon" proportioner 

at one quart per 100 square feet and thorough!y watered into the 

soil. EPTCwas applied to the dry soil surfaca at a rate of 10 and 

20 pounds per acre on a granular carrier and was rotary tilled to a 

depth of five inches. Check beds were left untreated at this time. 

lContribution Number 1178, Massachusetts Agricultural Experiment Station. 

2Screened bark from the paper industry. 

3sugar cane bagasse sold in bales for poultry litter.

391 

Post-planting treatments were applied on June 17th, the day 

after setting the plants. Each 5' x 20' bed was divided into four 

5' x 5' areas. The first was left untreated, the second was covered 

with two inches of bark, the third was covered with two inches of 

sugar cane, and the fourth was treated with 5 percent granular CIPC 

at a rate of 8 pounds per acre. 

Plants used in this experiment were growing in two inch bands 

prior to planting in the beds. Five plants each of the followlng 

varieties were set in each 5 I X 5' area of the beds: Euonymuspatens, 

Rhododendron yedoense poukhanense, .!!!!!!!!!.!!!! browni, Thuja . 

occidentalis, and Viburnum juddi. An exception to this was EPTC 

plots where a few plants of each variety except Viburnum juddi were 

used. 

RESULTS 

Survival of plants was markedly influenced by the chemical used 

as a pre-planting treatment. The effect of post-planting treatments 

generally did not produce as marked an effect. Total plant survival 

in the Methyl Bromide treated plots, 293 out of 300 plants, was greater 

than the check, 274 of 300 plants. Casualties were greatest in the 

DHrTplots where only 96 of 300 plants lived. SMDCalso had losses 

greater then the check as 243 of 300 plants survived. In the DMTT 

plots. more Euonymusand Taxus survived when mulched than not mulched. 

More even soil moisture conditions under the mulches probably enabled 

these plants to survive with damaged root systems until an adequate 

system was regenerated. 

Ten days did not prove to be sufficient time for the DMTTto 

dissipate, as evidenced by the plant loss. Survival results with 

SHOCpossibly also would have been better had a longer time elapsed 

between treating the soil and setting out the plants. 

The vigor of growth parallelled the number of plants which 

survived. Thus, generally better growth occurred in the Methyl 

Bromide and check plots than in the DMITand SMDCplots. Again, 

this was probably due to the damage to the root system at the time 

of setting by the herbicidal residue. 

Growth of plants on plots treated with EPTCat a rate of 

10 pounds per acre was equivalent to the check. The 20 pound 

rate caused inhibition of growth but did not cause any casualties. 

Weed control effectiveness is given in Tables 2. 3, and 4. 

Readings were taken at approximately monthly intervals. July 10, 

August 8. and September 15, after treating on June 6. The check 

plots were weeded on July 11, and all plots except EPTCwere weeded 

on August 11.

392 

During the first month little weed growth took place except 

on the check plots. Sugar cane mulch proved to be the most 

effective secondary treatment on these plots followed by CIPC and 

bark mulch. 

By the second month the check areas of all plots except those 

treated with EPTCneeded hand weeding. The EPTCplota were completely 

clean at this time. Sugar cane mulch continued to be the 

most effective post-planting treatment. On a rating scale of 

, area covered by weeds CIPC looks superior to the bark mulch. 

Actually, fewer large weeds covered the surface.in the bark mulch 

while,many smaller weeds grow in the CIPC areas~ It is easier to 

eliminate a few large weeds than it is many small ones. 

The third reading was taken on September 15, approximately 

one month after all plots except EPTChad been weeded. At this 

tima, the EPTCplots were still weed free. The amall amount of 

weed growth that occurred on the mulched plots following weeding 

is the molt notable feature of the results of this date. Any, 

residual effect of CIPC appears to have disappeared by this time. 

During October some henbit and chicl~eed began to develop on 

the ,EPTCtreated plots; however, the growth still was not as heavy 

al on plots treated with other materials. 

CONCLUSIONS 

EPTCappears to be a very promising pre-planting herbicidal 

material when applied to dry soil. A pilot study set up August 5 

indicated that this chemical in liquid and granular form was less 

effective on moist soil. 

Methyl Bromide continues to besomawhatsuperior in herbicidal 

effectiveness to Dl1rT and SMDC. Better groWth also resulted where 

it was used, possibly due to its shorter residual life in the soil. 

Sugar cane mulch proved to be the most effective of tha 

post-planting treatments. 

llEPERENCES 

1. Ticknor, R. L., and E~C. Gasiorkiewicz (1958). Pre-planting 

Treatments for Weed Control in Nursery and Herbaceous Ornamentals. 

Proc. NEWCC12:114-8. 

Acknowledgment is made to the Stauffer Chemical Companyfor 

financial aid and chemicals; to DowChemical Companyand Union Carbide 

and Carbon Corporation for chemicals; to Brown Paper Companyfor bark,

( 

TABLE 1 

Average Plant Survival in Pre-Planting Treatments. Treatments Applied June 6. 1958. 

Plants Set Out June 16. 1958. Record Taken September 15. 1958. 

CHECK BARK CANE CIPC Total 

Number 

E R TA TH V E R TA TH V E R TA TH V E R TA TH V of Plants 

Methyl 

Bromide 5 4.6 5 5 4.6 5 4.6 4.6 5 5 5 4.3 5 4.3 5 5 5 5 5 5 293 

DMrT 2.3 0.3 1 0.3 0 3.6 0.3 3.3 2.3 0 4 0.3 3.3 2.0 I 3.6 0 1.3 2.3 0.3 I 96 

SMDC 4 3.6 4.6 4 3 /4.3 4.3 4.6 4 2 4 3.3 4.6 3.6 3.6 4.6 4 5 4.6 4.6/ 243 

CHECK 5 4.3 4.6 4.6 4 4.3 4.6 5 4.6 4.3 5 4.3 4.6 4.3 4.6 4.6 3.3 5 5 4.6 274 

Total Number 

of Plants 211 229 230 235 

E - EuoL)ymuSpatens 

R - Rhododendron yedoense poukhapense . 

TAnI!!!!!. media browni 

TH-'~huja occidentalis 

V - Viburnum juddi 

VJ 

-0 

""

394 

Table 2. Results of Pre-Planting Treatments. 

Treatments Applied June 6. Results July 10. 

~ ~ £!!l! ~ 

Methyl Bromide Rep 1 2 0 0 0 

Rep 2 0 0 0 0 

Rep 3 0 0 0 0 

DMl'T Rep 1 0 0 0 0 

Rep 2 1 0 0 0 

Rep 3 0 0 0 0 

SMDC Rep 1 2 0 0 0 

Rep 2 0 0 0 0 

Rep 3 0 0 0 0 

EPTC 10 lbe. clay 0 0 0 0 

10 lbs. verm. 0 0 0 0 

20 lbs. verm. 0 0 0 0 

Check Rep 1 8 4 1 3 

Rep 2 6

395 

Table 3. Results of Pre-Planting Treatments. 

Treatments Applied June 6, Results August 8. 

~ ~ ~ .ill£ 

Methyl BroDlide. Rep 1 9 8 0 3 

Rep 2 5 1 0 0 

Rep 3 8 4 3 0 

DMTT Rep 1 8 9 0 7 

Rep 2 10 4 4 2 

Rep 3 3 4 3 0 

SMDC Rep 1 10 4 3 2 

Rep 2 6 7 4 4 

Rep 3 9 2 3 3 

EPTC 10 Ibs , clay 0 0 0 0 

10 Ibs, verDI, 0 0 0 0 

20 Ibs. verm. 0 0 0 0 

Check Rep 1 10 4 3 4 

Rep 2 7 3 5 6 

Rep 3 7 4 6 6 

Plots weeded on August 11. 

The ratings are based on a scale of: 

o - 

less than 4 weeds per square foot 

1 10 percent of the 1I0il surface covered by weeds 

It 

2 - 20 " " " 

" 

It 

3 - 30 

4 - 40 " " " II 

5 - 50 " 

" II 

II 

6 - 60 

" " " 

7 - 70 " " 

II It 

8 - 80 

II II 

9 - 90 

II II 

10 - 100 

II 

II 

" " " "

396 

Table 4. Results of Pre-Planting Treatments 

Treatments Applied June 6, Results September 15,195S. 

Check 

~ ~ ill£ 

Methyl Bromide Rep 1 3 2 0 4 

Rep 

., 

2 .J 0 0 3 

Rep s 0 1 0 0 

DMIT Rep 1 5 2 1 9 

Rep 2 7 2 1 7 

Rep 3 10 4 2 10 

SMDC Rep 1 8 2 0 8 

Rep 2 6 2 0 7 

Rep 3 8 0 1 6 

EPTC 10 Ibs. clay 0 0 0 0 

10 lbs. verm. 0 0 0 0 

20 Ibs. verm. 0 0 0 0 

Check Rep 1 10 2 2 10 

Rep 2 5 1 1 6 

Rep 3 10 3 3 10 

The ratings are based on a scale of: 

o - less than 4 weeds per square foot 

1 - 10 percent of the soil surface covered by weeds 

2 - 20 " " " " " " " " 

3 - 30 " " " " " " " 

4 - 40 " "/I 

5 - 50 " " " " 

It· 

/I 

6 60 7 - 70 8 - SO " " /I 

/I 

9 - 90 " " 

/I 

10- 100 " " " " " "

CIIE1:~ICAL 

WEEDCONTROLIN ElTljRGRE1'NURSERIES 

397 

John F. 

Ahrens 

The Connecticut Agricultural Experiment station, New Haven, Conn. 

Increasing labor costs make it imperative for commercial nurserymen to 

adopt ne~rer methods of controlling weeds. Elimination of hand hoeing is desirable 

from the standpoint of plant injury as well as the labor cost 

consideration. 

Two preliminary experiments were conducted in 1958 to evaluate the effects 

of several herbicides in certain evergreen shrubs. In one trial the 

herbicides were applied to 3-yr. old Taxus liners which had been field grown 

for 1 year. In another, the herbicides were applied to 2-yr. liners of Taxus, 

Tsuga and Pieris one week after transplanting to the field. 

, Liquid formulations were applied overhead i~ 84 gal. of solution per 

acre with a knapsack sprayer. Granulars were applied with a 24" lawn Beauty 

fertilizer spreader. Treatments were replicated 3 times with 4 control plots 

per replication. 

The first experiment was conducted on Hartford sandy loam soil using 

Hicks, Hatfield and compacta yews as the test plants. Plots were 15' ( 6 

plants) long and 54" ( 4 plants) wide. The area between the 2 center rows 

was evaluated. Applications of treatments sho~~ in Table I were maae on 

April 19 and aLain on June 4 after clean cultivation and hoeing each time. 

About ~" water was applied with irrigation immediately following application. 

Dominant weeds during early spring were chickweed and pineapple weed and dur- '; 

ing the summer were crab-grass, annual bluegrass, smartweed, lambs quarters, ," 

amaranthus species, pineapple weed, chickweed and vrild carrot. Evaluations 

of plant injury shm1ed the following: 

1. DNBPliquid at 12 lb./A applied to dormant yews in April resulted in 

some leaf burn. Growth in September was normal even after an additional 

treatment was' made with a granular formulation of DNBP. 

2. Neburon at 8 lb./A. caused some leaf injury and stunting in Hatfield 

yews after 2 applications. 

3. Two applications of' Na,trin at 6 lb./A caused definite stunting in all 

yews. 

4. Alanap-3 liquid caused stunting in Hatfield and compacta yews while 

Alanap 2Q-Gr. did ~t. 

5. Two 4 lb. applications of Simazin caused slight stunting in Hicks 

ye'l"lS. 

6. No stunting or other injury was observed ~~th CIPC, Sesone, CIPC plus

398 

Sesone, CDAAand CDECat the rates shown in Table I. 

The second experiment was conducted on Merrimac sandy loam. Plots consisted 

of 3 plants each of Pieris japonica, Tsuga canadensis, Taxus capitata 

and Taxus cuspidata. The 2-yr. old plants were lined out at 18" on May 8 

and the treatments shown in Table II were applied on May 15. Dominant weeds 

were lambs quarters, pigweed, axalis, crab-grass, purslane and carpet-weed. 

Injury evaluation on June 24 showed: 

1. No injury was obtained in the T. cuspidata or Pieris with arv chem 

treatment. 

ical 

2. T. capitata was injured by all chemicals except CDEC, CDAAand 

Alanap. Inconsistent response of injury to rates of Simazin and.Neburon 

indicate possible interaction of transplanting injury with herbicide rate. 

3. Hemlock (Tsuga) seedlings were injured by CIFC, sescne , CIPC plus 

besone, EFTC, Simazin, and CDAAat the rates applied. 

,!Teedcontrol obtained with the herbicide treatments used in the two experiments 

can be summarized as follows: 

1. In early spring DNBP, Simazin, Neburon, Alanap and CIFC plus Sesone gave 

fairly good control of chickJeed and pineapple. 

2. vJhen applied again on June 4, good to excellent control of broadleafed 

weeds and grasses was obtained withall chemicals except Sesone, Alanap and 

CDM. ~Jhen applied on May 15 in a simil1r SOil, however, single treatments 

of Sesone. 6 Ib./A and Alanap, 4 lb./A. gavegood weed control for 4-5 weeks. 

3. EFTC. CDAAand CDECwere more effective after June application than 

after April or May application, but this may have been due in part to residual 

activity from the April treatment. Rainfall in the 2-week period following 

the May treatment was 1.6" compared to about 1.2" following June treatment, 

including the 0.5" of irri~ation water applied. 

4. Simazin. neburon and natrin gave longest residual weed control. 

5. The 10% granular CIPC was more effective than the 5%formulation. 

- 

6. eIPC, 4 Ib./A, plUS Sesone, 4 Ib./A was more effective than CIPC. 

R lh f~ " .... q""",.,.. h lh /«.

TABLE1. 

PRE-ELERGEHCE ".'EEJ) CONTROL IN ESTi-.BLISHElJ ThAUSLU~__S 

'!'REA'lEDAPRIL19 ANDJUNE4 (a) 

TrL.:,tm",nt active May28 July 7 July 24 July 30 Comparative growth (b) 

rate Ball Grass Sept. 5 

Ib./A . 

- - - - - - - -, _.- - 

Control 1.4 1.3 1.1 1.1 100 nonnal 

5'tor.CIPC 8 4.7 6.7 7.0 3.0 

II 

12 7.0 808 8.7 6.0 n 

10%Gr.CIPC 8 6.3 8.5 8.2 5.0 n 

399 

5%Gr.CIPC .j. 4 

liq.Sesone 4 

8.3 8.0 7.3 4.0 

II 

Sesone 3 5.3 2.7 3.3 1.7 

11 

4 4.7 4.0 3.0 2.0 n 

6' '" 

5.0 5.3 4.3 1.7 

11 

Neburon 4 8.3 9.8 9.3 9.1 8.3 

11 

8 9.7 9.7 9.1 8.7 sl.stunting Hatfield 

Alanap-3· 4 6.7' 2.3 1.3 1.0 al.stunting Hatfield 

and compacta 

Alanap 20-Gr. 4 8.7' 1.3 1.7 1.0 normal 

Gr.EP'IC 4 6.7- 9.0' 1000 8.3 7.5 sl.stunting Hicks 

8 6.0 9.5 10.0 9.3 9.0 

11 II II 

Natrin 3 4.3- 8.7 9.2 7.8 6.8 sl.stunting Hatfield 

6 7.7 9.8 10.0 9.3 8.4 stunting-al1 varieties 

Gr.Simazin 2 7.7 9.7 8.0 6.7 nonna1 

4 8.7 10.0 9.5 9.3 8,9 sl.stunting Hicks 

DNBPliq. 6 7.7-' 9.3- 7.7 4.5 nonnal 

then Gr. (c) 12 9.3 10.0- 9.2 8.8 7.9 

11 

Gr.CDEC 8, 6.0- 8.3 7.7 3.7 -' 

11 

Gr.CDAA 8 3.7- 6.7- 7.7 3.3 

11 

(a) 1 is no weed control, 

10 is complete weed control. 

(b) Taxus hatfieldi, T, hicksi and T. compacta included. 

(c) liquid DNBP·first treatment, 10%granular second treatment.

400 

T./(BLZII. PF.E-EME}~GENCE WEEDCONTROLm 2-YEARLINEIcSOF TAlCUS, 

PIERIS AND1SUGA,T.RA.NSPLANTED MAY8 AND'lRE/('!'EDMAYlS. 

WeedControl (a) Injury June~ 

Treatment active June 23 Juli9 July 16 Taxus Taxus Tsuga pier is 

rate 30 days 46 days S3 days capi- cuspilb./A 

tata data 

Control 1.S 1.2 1.0 1.3 1.1 1.3 1.2 

S%Gr.CIPC 4 4.2 3.0 1.3 1.6 1.0 1.& 1.4 

8 7.4 6.0 S.3 1.8* 1.1 2.1* 1.2 

12 9.7 8.0 7.3 1.7 1.1 1,& 1.2 

10%Gr.CIPC 8 8.2 7.S 7.3 2.3* 1.2 1.3 1.2 

(12%Gr.CIPC 4 9.7 8.S 7.8 2.0i~ 1.3 2.0* 1.1 

plus Sesone) 4 

Sesone 3 6.S 4.7 3.0 1.3 1.1 1.7 1.3 

6 9.3 7.2 6.0 2.~ 1.4 1.8* 1.2 

lIeburon 2 9.0 8.0 7.S 1.8* 1.0 1.2 1.0 

4 9.9 9.7 9.S 1.3 1.0 1.4 1.3 

Alanap-3 4 8.9 5.3 . 3.3 1.6 1.0 1.2 1.2 

Alanap 200 4 7.5 4.8 3.3 1.4 1.2 1.3 1.1 

Gr.EPTC 4 5.4 3.2 1.3 1.3 1.0 1.2 1.1 

8 5.9 4.7 3.3 2.3* 1.2 1.8* 1.2 

Natrin 3 8.0 7.5 7.1 1.6 .1.1 1.2 1.6 

6 9.0 8.8 8.9 2.~ 1.2 1.6 1.2 

Gr. Simazin 2 7.7 5.3 3.3 2.3* 1.0 1.3 1.0 

4 9.2 8.5 8.0 2.2* 1.2 1.9* 1.3 

6 9.9 9.2 8.7 1.7 1.0 1.6 1.2 

Gr.CDEC 6 5..7 3.3 1.3 1.3 1.0 1.1 1.2 

Gr.CDAA 6 S.2 3.7 2.3 1.2 1.1 2.2.* 1.4 

(a) 1 is no weed control, 

(b) 1 is no injUry, 

10 is complete Wbedcontrol. 

4 is dead rlAnt 

~

Arthur 

Bing 

Cornell Ornamentals Research Laboratory 

Introd'.\ction 

Several herbicides ha.ve bee': found to be quite useful in nursery 

~feed control acd ~ave bee" reported at :.:-reviaus 'r.eetinp;s of the 

Northeastern I'TeedControl Conference (1, 2, 3,4, , )•. Some herbicides 

are now used by commercial nurserymen. The "ur.."'o,se,of these experiments 

is to test severalof' the older chemicals for both crop tolerance and 

weed control. The experiments extend over a per-Led of several vears to 

stu~r ryossible cmnmulative effects of the herbicides. 

Methods and Results 

In the first series of tests, fifty fo,;)1:;r01fS of' nurser' r,lants 

were.c 1ivided drrto four treatment areas across the rows. Treat'lle'1ts ~fere 

Karnex TM,at 1 1/2 nounda in 100 gallons of "rater r;er acre in 1957 and 

an equivalent amount of' Diuron granular in 1958, Chloro IPC emulsifiable 

8 pounds in 100 gallons per acre, twice each year, Chloro IPC % granular at 

8 pounds actual ner acre twice a year, and a!" untreated lot. "Teed and 

crop growth were -r:eriodicall·· observed. After two ~r('T,7ing seasons the 

plants are removed as in re~ular nureerv nract:i.ce. The treated areas are 

replanted the followin~ s"Jril'lf! a nd the treatments cont'.nued .. 

Plants tested for two years and showing no injury from Chloro Il'C 

were Rhodode'1drom carclinianurn, Rhododendron catawbiense, 'laxus cllspidata 

capitate, Leucothoe cate:Cbaehand ~ ~pfer!. Plants tested for one 

year mewing no injury were ~ crenate cOl1vexa.. Enkianthus campanulatus, 

~ sem,.,erviens J and Rhododendron catawbienRe q ~ Hindogeri gram in 

Chloro IPC treated soU were much snaller than the controls. Galinsoga 

parvif'lora which was net controlled by Chloro IPC ha s become more of a 

problem each vea r in the Chloro !PC plots. Erigeron also ,o/&s110t c~ntrolled. 

There was r:ood control of most other weeds esrecially purslane, chic!cweed J 

and seedlu1g grasses. Untreated plots were overrun with Galinsoga, pt~slane, 

henbit, chic~,eed, and Erigiron unless freque~tly cultivated. 

The Karrrex plots ,,,ere weed free the fir~t sea son Ejxcent for an 

occasional TJlc:.11tof Barnyard grass. In the second season the Karmex "llots 

were essentiall'r weed free. The follc)T.Tin'- cro"s ',rare t'.nill,j'U"E!daf.t~r two . 

seasons: Rhododendron carolinianum, .Rhododendron cata~Tbie.,s.e, ~ kaempferi, 

~ HinodeRiri, and teucothoe catesbae1. ~ capitate showed injuryon 

se-ne plants. lIfter' one season,; Iiex crena'ta convexa showed some yellow. 

leaves but Enkianthus,BUXus,semiirvIreiis,andRhododendron catawbiense 

showed no in,jurv and grew noma ]Yo

402 

In the second series two rows of establ-l.shed Taxus Cus"l~"r1ata 

were treated one ro·! with Chloro !PC at 12 rounde YJer-acre ell3 the :>ther 

at 16 ",oun'P ~er acre, Treat'1lents were Madet"r.ce a year far three years 

u!"iM liquid a..,r:licati:>ns the first "ear and ~nula.r the second and third 

years. There was no cro" injUlT but Gal1n!"oga became a real problem. 

Ever" other TaxUBwas removed in the 1&te sm'in"( of 19,7 and 

pl,.nted Ln bit) ne~T x:c;;s:One row was treated on Ua3' ·27with 2 pounds 

of Karmex rJJ oer aore the other at 4 pounds per aore. Appli.cati"tls 

were repeated on June 3, 19,8. There was severe injUI7 at the 4 pound rate 

the first season but there was only slight injury on some nlants the 

second season. Injury from the 2 pound rate was only sl ight the first "ear, 

none the second season. The injury was a severe chlorosis and about ,r'of 

the plants ~rerekille(' from the 4 pound per acre ap,?lication. 

Discussion am Summary 

Karmex diuron granular shows great promise as a herbicide 

far nurserv sbock but may be harmful to !lex crenata ccnvexa and 

newly planted "81-78. chioro IPC injured Azalea Hinodedri but none of the 

other plants tested. Galinsoga becO"I1esquite a problem in Chloro rro 

plots. The colored slides show the effectiveness of Chloro IPC in a 

comraercial nurseIj1'. 

References 

1. Bin~, A. Tolerance of ~OIIIe Perennials and T!looc:tvPlaritsto '3esone 

(Crag 1)1) and Chloro IPC. !-T.TI:."l.C.C.12, 124-129. 19S8. 

Pridham, A.M.S. Granular Herbicides for Weeds in Ground Cover 

Plantings, !-T.E.W.C.C.. ~t 108 -110. 19S8. 

Pridham, A.M.S. Granular Herbicides tor Weed Control in NurlSElr,y 

Pla·1t i.ngS, lJ.~.H.C.C. 3lIllO-111. 19~. 

4. Ticknor, R.. L. and P. F. B'obUla. Tolerance or Taxus and 

Juniperus to "!elected Herbicides, N.E.l>T.C.C."TfiiJ.2-113. 19$8. 

Ticknor, R. L., and P. F. Bobula. Chemica.lWeed Control in 

Miscellaneous Nursery Stock.N.E.vT.C.C. 11' 69-72.. 19,8

4C3 

EVall~tion of Simazin in the Control of Seedling and Established 

Perennial Weeds in Nursery and Ornamental Plantings 

A. M. S. Pridbam, Cornell University 

Field tests with Simazin in 1956 and 1957 demonstrated consistent and prolonged 

residual control of seedling weeds following application of spray or gr~nular 

formulations of Simazin. 

A test was run under the controlled environment of a greenhouse. Simazin 

granular formulation on attaclay was used to control the iElrmioa.tion of 

redtop, Agrostis alba. Watering was ione through time clock controlled 

misting system equipped with Florida nozzles. Under the favorable conditions 

maintained for germination, 1 pound of active S~zin per acre prevented 

emergence and growth of redtop seedlings. A second test was run in August 

1958 with simi~~ results. In both tests CIPC prevented germination at 

~ to t pound pe~TA~tive. Jiuron and Fenuron were also effective at ~ pound 

active per acre levels, Neburon at 4 lbs. active per acre. 

Field tests were made during 1957 and 1958 at selected intervals when the 

following situations prevailed. 

1. Environment favorable for weed germination: - this ~ften follows 

CUltivation, either to prep~re soil for planting or to remove existing 

weed growth by rototilling and/or hoeing. It is preferable that crop plants 

be dormant or have mainly mature tissue in stems and foliage. 

2. Weed seedlingS small growing ril.pidty, with little or M mature 

tissue in stem leaf or bud. Crop plants preferably dormant or have mature 

tissue in stems and foliage. 

3. Perennial weed, Agropyron repens, in first flush of regrowth in 

spring or following later cutting or cultivation. Crop plants should not 

be in their main growth period, May 1 to June 15. 

4. Weeds of all 

August. Crop plants 

types at summer maturity, 

also at summer maturity. 

e.g. late July an~ early 

Sprays used directionally for 

"in row" treatment. 

Control as used in this report means that on a rating basis by 2 or 

more observers, a plot remained free of all weed growth for a period of at 

least 3 months after initial action following treatment. When2t or more 

individual small weeds (t~tf") survive in a pl.ot of 100 square feet, then 

control has not been reac~ur has been lost. Untreated or check plots 

typically contained more than five individual weeds per square foot and 

average from 500 to 2,00·' grams of green we1gb.t of weeds in 3 months. 

Weed populations in plots treated with 

Fall 

ChICkweed, Stellaria me,ia 

AIinual blu.egrass, Poa annua. 

Groundsel, Senecio vulgaris 

Simazin (MlJor) 

~ 

Lambs quarters, Chenopodium album 

Pigweed, Amaranthus retrClflexuB 

Purslane, Portulaca oleracea

4:)4 

Others frequent but not predomi~nt 

Yellowroeket, Barba.rea vulglris 

Quo.ckgrass, ~ropyron repens 

re.nliel1.n, 

Pla.nta.in, 

Taraxicum off1ci~le 

PLmtago major 

Herbicides Used in Addition to S1mazin 

Herbicide ~ Rate of doctive ingredient per ,J,cre 

Amino tr1e.zole granular 5 

Atr:1zine spray 4 - 6 - 8 

CIPC granular 4- 8 - 12 

spra.y 4-8-12 

CIPC-SES granular 4-8-12 

Diuron " 2 - 4 

DN -" 4 

Endoth3.1 " 2 - 4 

Carlon so;ro.y 4- 6 - 8 

Neburon granular 4- 6 - 8. 

" spray 4 - 6 - 8 

Propazine " 4 - 6 - 8 

S1mo.z1n granular 1 - 2 - 4 - 6 - 8 - 1(') - 12 

spray 6 - 8 - 10 - 12 

Triet

Situation 2. Small weed seedlings to 3-6 inches in height 

4('5 

d~tes 

Treatment 

9/57 

11/58 

9/5'7 

7/58 

Orn~ental plant 

ground covers &liners: 

Euonymus fortunei 

Hedera helix 

Iberia sempervirens 

Juniperus horizontalis 

Pachysandra terminalis 

Vinca minor 

Buxus sempervirens (inj.) 

Taxus cuspidatu. 

Thuja occidentalis (inJ.) 

Taxus cuspidatd. 

(Senecio 

m

406 

SUIllIllation 

Situ~tion 1, germi~tion weeds. Twenty-two plots of Sim~zin were in 

this group. One hundred per ceritcontrol w~s present in all but 1 case - 

gr~nul~r Simuzin at 4 pounds or more of active per acre. 

Situation 2, Weed see~1ngs young and active. ThertJ :lore 12 plots in 

this group. Ten ~re classed as satisf~ctory control. All plots at the 

8 pound level resulted in control'but granular formulations were only 

p~rtly effective at the 4 pound level. 

Situation 3, Young growth in Agropyron repens. Five plots were in 

this category and all received Simazin as a spray formulation. Treatments 

were made in cool weather, spring or fall, at 5 to 12 pound levels of 

407 

AFFBO'l'Sclli'serlE HERBICIDESON Ntm.~ERY 

STecK 

Arthur 

Bing 

Cornell Ornamentals Research Laboratory 

Introduction 

The experiment reTJOI"tedin this paJ:Elris a continuation of ~ ) 

''forle reoorted in t he 'Tevious paper: "TwoYears Tests with Diuron and 'Chloro ° 

IFC on Nuraery "'tock." This series was started in the spring of 19,8 to . ° 

att~dy" crop tolerance and weed control in areas treated with some older 

and some eX'1erimental herbicides at several concentrations. ,seventeen rOlfS 

of nursery stock were Dlanted in late May. In thirteen rows 100 plants were 

set out at two foot intervals. In 4 rous, plants of smaller ultimate 

:size l~ere :set out 200 per row 201ter"& ti.ng two variet1e s. The rows were 

three feet a\"1l.rt center to center. Individual treatments were 'Jade across 

the rows covering one plant each of 21 varieties except gladi"lus 1~hich were 

plc.nted 6 corms for each treatment. Materials and rates are ShCMl 

in Table I o The field was raked June 3, irrigated June S, and granular 

Simazin, Diuron, and Ohloro !PC apo,-Ued on June 6. Rain held up other 

treatme11ts until June 11 'fhen the reminin::: treatments were ap"Ued. 

In late .'l.uc-ustthe ':'lants were rated for injUZ1'b1 two obwervers. 

In table IIa and lIb are shown the minimUlllrate of each herbicide that 

caused serious injury' to the crop. A clash (-) indicates no 

apparent injury at that time. In cases ,7herethere was inj'U1'1'at 

a lower rate of a herbicide but not at higher rates no injury is shOlfO in 

Table II. There i" a very" much greater tolerance of lllBI'ly T'llants to 

granular Karmex diuron than to the liqllid ap"pU.cations. The Simazin 

granular wa~ ~ot harmful to the "'lants but also did not leill the weeds 

so the results 1)robab1y were d1l8 to a !loar foraulat1on. Enkianthus was 

injured by rates as 1001as 2 pOlmds "'81" acre oJ: liquid 5imazin ar liquid :"' 

Diurcn. Armeria was adverse~ affected by most herbicides at lOW' 

rates oJ: ap',l:l.ca.tiOt'.s. Pieris, Privet, Taxus, Forsythia, Rhododendron, 

and Leucothoe l~ere rather tolerant to 'IIost herbicides exceTlt KarmexIW 

liquid. 

On Ju1;y"15, a nursel'7m&n, a county agricultural agent, and the authcr 

rated all the plots for weed co"!trol. The field had a «ood native stand 

of nutgrass, (cYPerus esculantus , red root (Amara"o1thusretrofiexus), 

lambs quarter ~odium a mustard.and ragweed (Ambrosia artemill1it'ol1a) 

Table III Sh01'f1l the 'n:tnUnUlllrate ,,1' each herbi.cide that produced satisfactory' 

cootrol. of the major weeds. The out eta l'Xiing result was the control of 

nutgrass by Geig 30027. At UfO nounds j':Sr a.re there was partial control 

(2P) while at the 4 and 8 pound rates there was wr r good control. Nutgrass 

in the higher rate Karmex IW plots was Nortia1J:y' contro1'.ed a. 

evidenced by redueed growth later flowering, and considerable root injU1T 

which made it easy to !,ull the Brass.

408 

-/ 

In late July all weeds in al 1 plots were pulled and 

the space bet~feen rows lightly rototilled. On August 19, all granular 

treatments were repeated. In addi ticn three plots across the rows 

'ljeretreatedwith granular !trlone at.2!!, 128, and m, pounds per 

acre. In November,the Karmex diuron granii'.iAr plots were all clean and 

practically all plants in good condition. !Wlone granular at all rates 

killed all the weeds many of whi.ch were up 3-4 inches but there was crop 

inj1,lZy at the higher rates to all crops but ~ucothoe. Other 

granulars were not too effective. The plat.s that received only the 

original higher liquid ap"Ucations of Karmex Jlo1and S1mazin were still 

weed free in November in spite of the rototilling in July. 

Discussion 

and Summart 

Karmex diuron granular shows great promise as a herbicide on 

nursery stock While the liquid is quite harmful. Karmex granular may not 

be safe on nex crenata convexa. S1mazin and Karmex have a long lasting 

effect, in the soil at sufficient rates and should require only one 

ap"lica.t~on during one growing season. Geigy 30027 shows promise for nutgrass 

control even though it is harmful to some ornamentals. This:l 

series is only intended ssa quide to further studies on weed' 

control of ornamentals. The present stuqy- is being' continued .. 

Acknowledgments 

The author wimes to thank the following for furnishin" the plants 

used in these exnerimentsc Hicks Nursery, Martin Viette Nurserv, 

gtto Muller Greenhouses, and the State University ot NewYork, Agricultural 

and Technical Institute at Farmingdale, NewYork. The assistance given by 

the Nassau Oounty Agricultural Extension Service was an1mportant 

factor in the planting and rating phases (of the eX!8rirrsnt.

409 

Table 

I 

Herbicides Used in Nursery Tolerance Study 

Material 

Simazin 8.5% granular 

Kannex Diuron granular 

Simazin 50%WP 

Karmex rJiI 8Ct'WP 

Geigy 30026 WP 

Geigy- 27901 WP 


Gei.gy 30031 emulsifiable 

Geigy 31L!35emul'::,itiable 


Sesone 90%soluble pO'Tder 

O:c'C emulsifiable 

CEO 5%granular 

aIFC6%-Sesone 4%gra."1ular 

CIFC 4%-Sesone 4%granular 

Neburon 180$%WP 

EPTC5%gran ul,ar, :, 

Rates 

used in Ibs actual/A 

1, 2, 3, 4, 6, 8 

1, 2, 3, 4, 6, 8 

1, 2, 3, 4, 6 

1, 2, 3, 4, 6 

2, 4, 8 

2, 4, 8 

2, 4, 8 

2, 4, 8 

2, 4, 8 

2, 4, 8 

3, 6, 9 

6, 8, 16, 24 

, 8, 16, 24, 32 

3t 2, 6+4 1 946, 12+ 8 

2+-2, 4+4, 6 ....6, 81'"8 

2, 3, 6, 8, 12 

3, 6

) 

) 

Table 

CroP Tolerance 

IIa 

to Herbicides 

.MinimUll1rate .in ~oun(l" ;.ar acre era" does not tolerate (See Table I for rates used) 

,. 

SIN Irarmex SimadD ' !annex Geigy Geigy Geigy Geig 

Gran .. DiurOl1 Liq. I.W 30026 21901 30028 3003 

Gran. 

------------------------------------------------- 

Gladiolus var. Snow Princess .. - 6 6 

Enkianthus cam~ulatu~ 

* 

~ 2 a 8 ~ 2 

Tsyg,a canadensis - - - 1 8 

~ieponica 

Ligustrum ovalifolium - - - - 81 - - 4 

nex crenata convexa - - 3 1 - 8 - 8 

Taiiis cUEddata ca!li_tata - - - 4 

Taxus media Hi-cksil - - - 3 

Forsy~termedia ... - - 3 - - 41 

Rhododen~ron catawbiense .., - - 4 

Leucothoe catesbaol - - - 6 

felphinium HYbrids .;.' 

- 1 2 4 - 2 2 

Philadelrhus coronarius - - - 4 8 - 4 

Azalea HinOdegirl - - 2 1 2 8? 2 2 

Azalea Coral Bells - - 2 I 2 87 4 2 

&edum snectabile - 2 - 1 4 - 8 8 

Hedera helix - 3 - I 8 - - 4 

Sedum sP;- - 2 - 1 - - 8 8 

C1edumsp. - 2 2 2 2 - 4 2 

Armaria la ucheana 3 4 1 2 2 8 2 2 

Iberis se1"l'-ervirens 3 I 2 - - - - 2 

* No serious cro» injUl"'" at aIT'T of t'" ~ ra tes used is shown by a dash 

C 

rl 

...j-

( 

( 

Table 

IIb 

Crop Tolerance 

to Herbicides 

MinilllUlllrate in pounda per acre cro;"' does not tolerate (See table I for rates used) 

____________ _ 1J4!32 

Gladiolus var , SnOW' . 

Princess 2 

*- 

Fhkianthus ca~nulatus 8 

1m .ec..nadensis 

~ "aponica 8 

I.1p'ustrum ovali£oli'Ulll 141 4 

nex crena ta conve:xa 

Taxus ctlsTJidata ~itata 

Taxus media Hicksii 

Forsy-mntermedia - 4 

Rhododendrm catawbiense 

teucathoe ca tesbaei 

Lel phiniUII I&brids ? 4 

PhiladelPhus coronarius - - 

Azatea Hinodegiri 4 4 

Azalea Coral Bells 4 4 

Sed'UlllsEectabile - 4 

Hedera helix - 4 

Sedum sp.-- 4 

SedtD'llsp, 4 ? 

A:nneria laucheam - 

Iberia ~erlrcervi.rens 4 

orro £fI, ere 14- 

Geig)r Geigy eIFC CIFC Sesone 11% Sescne 14 

_1~21_ ~e.:!0Ee__ ~ig. __ G~ __ !!~ Ql'!Jl N~~2'!. 

24 

8 

16 

16 

6 

9 

9 

9 

16 

16 

l~O 

* No seri"us crop injury at an"of the rates used is 

mownby a dash. 

!b 

1 

1 

6 

6 

2 

2 

8 

6 

2 

~ 

I-' 

I-'

412 

Table 

III 

Herbicid2.l •.etion on '-Teeds 

rli!1.imumrate in r:>Ui:'lCS actual tha t prodi'ced satisfa.ctOlY '·reed control in 

troublesome weeds G 

Nut Red Iambs Rag Orab 

Material Grass Root Quarter Weed Grass Mustard 

Simazin 8.% gran -llNO. NO NO NO NO NO 

Kannex diuron 'Zf, gran NO 1. 2 1 1 1 

Simazin 50%WF 8P 1 1 1 2 1: 

Kannex rJN80%WP 41' 1 1 1 2 1 

Geigy 30026 ,a> 8 2 2 2 6 2 

Geigy 27901 WP NO 2 2 -2 8 2 


*** 

2 2 2 NO 2 

Geigy 30031 ernul. liq. NO 2 2 2 6 2 

Geigy 31435 ernul. liq. 81' 

Geigy 30027 WI' 21' 2 2 2 4 2 

Sesone 90%soluble powder NO 9 9 9 9P 6 

crro ernul. liq. NO 16 6 16p 16 6 

CIFOGran NO 8 8 NO 24 6 

OIPC 6%-Sesone4% Gran- NO 12+ 6 12t 6 NO 12+& 3t 2 

CIPC 4%-Sesone 4%Gran NO 4...4 4-1-4 6+6 6t 6 414 

Neburon 180% Gran NO 2 2 2 8 2 

EPTC% gran 3 NO NO 3 3 

* No oontrol at rates ueed. For rates see table I. 

** 81'particle centrol at 8 -powds. -- 

*** Insufficient weed population or other reason for not rating. 

"1' • '·i 

0' ',. l,

--~., __ 

'- 

CHEMICALWEEDCONTROLIN MAPLE SHADE NURSERIES 

John F•. Ahrens . 

The Connecticut Agricultural Expertment Station 

New Haven, Connecticut . 

413 

The successful control of weeds in orchards has indicated 

that hand labor may be v~rtuallye11minated in deciduous nurseries 

as well. This report is of a preliminary experiment in 

which several herbicide treatments were evaluated for their 

effects on weed control and tree growth. 

The trees used were Crimson King maples ranging from 1/2 

to 3/4" in diameter ( at 3' from sol1 ) and grown in a Hartford 

sandy loam soil. Plots consisted ot6 'trees and were 18' long. 

Treatments were replicated three times and two controls were 

included per replication. 

The post-emergence treatments were first applied on May 19 

to eXisting stands of bro$dleafed weeds and grasses which included 

chickweed, pineapple weed, downy brome-grass, curled 

dock, and annual bluegrass~ Sprays were directed in an 18" 

band ·over the row with a knapsack sprayer. The lower bre':lches 

.f the t r-eea were pruned so that no foliage was hit. Two 

rates of amino triazole and two DNBPPlus Dalapon combinations 

were applied a,s contact sprays in 84 gal. per treated acre. 

Table I indicates the percentage weed kill observed 2 

weeks after treatment (June 3). A second treatment was applied 

at that time. Excellent kill of all grasses and broadleafed 

weeds was obtained with the two applications of either 

2.5 or 5 lb./A of amino triazole. Annual bluegrass persisted, 

although stunted, in the DNBPplus Dalapon plots. Tree growth, 

as measured by average increase in diameter, was not affected 

by the treatments and no foliage injury was observed. 

The pre-emergence treatments were applied in 18-20" bands 

over the row on May 19 after hoei~. A rainstorm occurred 

shortly after application, and 1.8 of rain fell in the follOWing 

2 weeks. 

Weed growth fnllowing initial hoeing was slow even in 

control plots. Best residual weed control was obtained with 

diuron at 3 or 6 lb./A or Simazin at 4 lb./A, as shown in 

Table II. 

Summary 

~ 

..3"__ .. __~ ...._~

414 

grass weods was obtained with 2.5 or 5 Ib./A of amino triazole. 

Annual bluegrass appeared somewhat resistant to DNBP 

plus Dalapon. 

2. No growth inhibition or foliage injury of trees was 

obtained with any 0 f the herbicides tested. 

3. Diuron and simazin were very effective for long time 

weed control following ho edng , 

4. Great possibilities exist for the use nf combinations 

of amino triazole or dalapon with residual herbicides to eliminate 

hoeing. 

Table I. Effects of Contact Treatments on \~eed Control and 

Growth in Crimson King Maples 

Chemicals applied May 19 and June 3 in 18-20 11 band • 

Treatment 

--------- 

weedy 

control 

active 

rate 

Ibs./A 

(a. ) 

Weed Control Tree Growth 

Percentage Kill diameter . 

- 'June -~ - - - 'June -2~. . increase (rom) 

Grass ~ ~ 1i.ll - - - - - 

o 0 0 0 8.1 

Amino 205 70-80 80-90 95-100 95-100 7.7 

triazolo 5.0 75-85 85-95 95-100 95~100 8.9 

DNBPplus a·OPIUS 40-50 60-70 70-80 95-100 6.8 

Dalapon .0 

3.0plus 45-55 70-80 80-85 95-100 8.1 

8.0 

(a) On treated band.

Table II. Effects of Pre-emergence Herbicides on ~ebd Control 

and Growth in Crimson King Maf.les 

Chemicals applied May 19 in 18-20' band 

after clean cultivation and hoeing 

Treatment Active (b) Weed control Tree Growth 

(a) rate diameter 

______ l£s~! ___ lu!.Y_21 _ ~e.Et..!.2g __ In.£.r~a~e_(.!!!!lll _ 

415 

Control 1.8 1.5 6.5 

Diuron 3 9.2 8.7 7.6 

6 9.5 9.7 8.0 

Gr.Simazin 4 7.4 7.0 6.5 

Sesone 4 4.7 1.0 5.5 

Gr. CIPC 8 6.0 1.0 5.0 

Sesone 4 plus 4 6.3 1.0 8.1 

plus Gr.CIPC L~ plus 8 6.0 3.0 8.1 

(a) Treatments not mentioned as granular (Gr.) were applied as 

sprays. 

(b) On treated band. 

(c) 1 is no weed control, 10 is complete control.

(1- Geigy Agrioultural Chemioals, Division of Gei~y Chemioal 

Corrr":l""'7'1,t~.~"" 

4.16 

A DISCU9SIcm r>'1:Ra MOD!OF AC'DION, TOLF:PANC~ 

JU~T) 8/HL TYPB EFPFlCTSOF TH."lTRIAZIJIlES 

By 

Edwin O. Sohneider (1 

Sima~ine (2-ohloro-4,6-bis-(ethylamino)-s-triazine) was 

synthesized by Gysin and Knusli in the laboratories of J. R. Geigy, 

Basle, Switzerland. Simazine was released for herbioidal 

evaluation to experiment station and other workers in this 

oountry in 1956. Outstanding results, partioularly in oontrolling 

weeds in oorn with pre-emergenoe applioations, led to an expansion 

of researoh aotivities in the oontrol of weeds in oorn as well 

as in many other agronomio and hortioultural orops. Other 

triazine herbioides olosely related to Simazine were introduoed 

in the f?llowing years for evaluation on agronomio and hortioultura~ 

crops , The general herbioida1 aotivity of Simazine, when applied 

at rates substantially higher than for seleotive oontrol of weedS 

in orops, led to its oommeroial sale for this purpose in 1967. 

Label aooeotanoe for the use of Simazine for weed oontrol in oorn 

was granted by the United States Department of ~rioulture on 

April 19, 1968. Claims £Or weed oontrol in ornamentals were 

subsequently aooepted. 

This paper will disouss phases of the mode of aotion, orop 

toleranoe and soil type effeots of the triazines. 

TBE TTiIAZINJi',s 

------- 

A group of triazine oompounds related to 

released to numerous researoh workers and other 

Simazine 

workers 

have been 

in this 

oountry for study of the herbioidal properties. These ohemioals 

have been evaluated on many crops and aquatio weeds. Table I 

presents the ohemical struoture of the oompound along with the 

names and the solub~lity in water. 

c 

/\ /r 

I' 

( C 

":\ 

STPJCTU"EANDWAT~ SOLUBILITY:W SIMAZINF.: 

AND T"'R T{ELATSDC:1l1!'OUNDS 

--- _.-.. __...- ---,,---- ---_._------- 

Solubility 

in water 20-22 

-------- 

0C 

6.0 

70.0 

8.6 

20.0 

40.0

41'; 

Th'" aoute ,oCTI11to:tiottdesllof ilhe .trillUneloompounds. in 

Table I have been determined on both rats and mioe. The LD 0 

for Simazine against both test animals is in exoess of 5,OOgmg/Kg. 

The other oompounds are in the same :-a'nge of toxioity although 

the LD 50 ar-e scmewhab lower than for Simo.z1ne. 

Tests have demonstrated that oorn will tolerate rates of 

8imazine much i~ exoess of those neoessory for the oontrol of 

annual broadleaf weeds and grasses. Applications either before 

the corn appears or applioation to the emerged plant has resl~lted 

in no injury to young oorn plants. Roth (1) working on the 

metabolism of Simazine in corn found that the enzyme peroxydase 

probably oatalyzes the hydrolysis of Simazine within the plant 

shortly after absorption from the soil. Plants menti0ned below 

in Table II and many woody speoies of plant s have demonstrated 

toleranoe to Simazine. Probably these plants are able to deoompose 

3imazine.in the same manner as oorn , 

Apparently susoeptible plants cannot deoompose the absorbed 

ohtlmical or do so at a rate 80 slow that death of the plant ocours 

before decomposition of the ohemioal occurs. Tests have 

demonstrated that oorn, wheat and Coleus blumoi take up Simazine 

in about equal amounts but the latt~o-wi-rr-die when approximately 

5 PlO~{ on a green weight basis has been absorbed from nutrient 

solutions. Studies using radio aotive C 14 Simnzine have oonfirmed 

th~t the uptake in susoeptible.and resist~lt plants is very rapid 

and in about the same umount. 

Reoent experiments indioate Atrazine is deoomposed in oorn 

pIerrcs in the same manner as Simazine. Comoon tolerate all of 

the ohloro-triazines listed in Table I. 

Table II lists the orops that demonstrate toloranoe to the 

ohloro-triazines. These orops in generul do not show as hil!:h a 

tol~runoe to the oh10ro·triazin~s as does corn to Si~Azine. All 

of these compounds have suffioient herbici,hll aotivity to be of 

inte ··est.

41~ 

Tr j t.z1n

417 

The moet ou~standinf, one i8 Atr~zind whloh is oqual to Simazine' 

as a pr~-emerge chemioal in corn yet domonstrates exoellent ' 

contaot kill of small s,Hldling emerged weeds. Sevoral of ;me .,' 

other tria~inos are leaf absorbed to varying degrees but do not 

exhibit the spoed and thoroughness of kill as does Atrazine. 

Atrazine has demonstra~ed oomplete 'kill of tho common 

annual broadlaaf weeds and grasses in oorn when ~pplioations at 

2 and 4 lbs. aotual were made to oorn 4 inohestall with weeds 

t to 1 inoh in height. In, another test, oorn 12 inohes tall was 

treated at l~ and 2 lbs. aotual with weeds and grasses from ' 

2 to 6 inohes in height. The smaller weeds were oontrolled at 

both rates, however, velvet leaf (Ab~~~o~ ~eo~hrasti) was not 

oontrolled when 3inohell high or tnller.Grneses under 2 inohes 

we,'e oontrolled while the taller foxtail (f:etaria sP)J.) o.nd barn 

yard (Bohinoohloa orusgalli) esoaped with only stuii"tTng. No 

in.juryWa'Si1o-te"d'on any of -the co rn , 

FACTO~S ~FF~CTING TrmlretBICI AL ACTION 

_____ ..2.~T.r1!'l T".IAZINES' . 

"re-emorge .applio,tionsofSilIinzineund thu othllr trinzines 

ar e effeoti ve throu6h the roots, therefore lIIGisture must be present 

in,suffioient.amount in·one or more !"'!lins to ·oorl'Y the herbioide to 

the root zone of the weeds. To obtain the bast results moisture 

should be present in tho soil before and at the time of anplication 

o.s well llS fo Howing the treatment. Rain or overhead irri!!;stion 

must ooour to remove the ohemio~l from the dry surfaoe soil and 

leaoh it down into the root zon~. Usu~lly i inch of rUin is 

required in one shower to move tho Simazino downwar-d, although 

tho rapidity of evaporation at the surface and the amount of 

soil moisture at the time of the rain may affeot the requirement. 

Atrazine being more soluble then Simazinein the soil, may reqUire 

1 eee moi'stUl'e for movement into tho root zone. Moisture for 

th~se chemicals which are leaf absorbed is not oritioal. 

studios underway on the effeot of soil temperature and 

fixation by the oluy and organio mattor of tho soil are not 

ccno Iue rvo ,lt the presont timtl. Obeervnta one on the growth of 

plants indioate a rapidly growing plant under ideal conditions 

is killed more rapidly than one growing unde r low t emper-abur-e or 

drought stressed. Apparently the plant is able to abeorb more 

ohemfca l, us the root syetem will spread rflpidly in tho treated 

zone and aooumulate the Simo.zine o.t a muoh fuet.er rate'. 

Soils having a high organic matter ar high olay oontent 

require rates of the ohemioal in exoess of tho ruquirGmant for 

sandy soils. In sand the low affinity of the sund for the ch~mioal 

allows movemonf of Simo.zine into the root zone IOOreeasily. In

hUclvi,3r ~,~ils, th« (\l~y adsorption rno.kds 1\ high",,- rut" nvousso.ry 

in o~d3r for an nmpld amount to pcnotro.to to tho germino.ting 

ZOnJ. 

RESIDUALACTIVITY 

S ime.zin" is 0. v

SOIL INCORPORATIONOF SELECTIVEHERBICIDES 

By: 

An;;ogn~ni, J., D. F. Dye, G. F. ProbandI; & R. Curtis* 

Tne use of selective herbicides a.pplied prior to weed emergence, 

in the past, has been limited primarily GO soil surface sprays. 

Recent experimental and commercial results have shown EPTC(EPtarn) 

and certain other selective herpioides to have increased activity 

and certain other chemicals to have decreased activity when incorporated 

into the soil. 

Research workers as well as growers are well aware of the .variab11hy 

in results obtained with soil surface applications of herbicides. 

This variability has led to the necessity of making recommendation~ 

on the basis of specific cl1Jna~+c factors and farming practices. 

It has been shown by experimental and commercial applications that 

5011 incorporation of herbicides o·ffers the following advantages 

over surface applications. 

Increases 

Activity: 

It has been determined that the .acti'vity of EPTC is much greater 

When it is incorporated into the so11 than when it is merely applied 

to the so11 surface. Thil;! may al so be the case with some 

of the presently known herbicides as well as with some of the 

herbicides of the future. 

Greatly Minimizes Variability Due to Soil Moisture, Tilth, & Type: 

Satisfactory weed control With surface application of herbicides is 

dependent on a specific combination of the above factors. The 

specific combination required varies according to the type of herbicide 

and the weeds and crops involved. 

Reduces Influence of Subsequent Rainfall and Type of Irrigation: 

With surface applications the degree of herbicidal activity, in 

many cases, is influenced by the interval to and quantity of 

moisture. ActiVity can alao be inflUenced by the type of irrigation. 

i.e .. sprinkler vs. furrow irrigation when·surface app~~", 

cations are uaed. Soil incorporation minimizes this influence. 

* Stauffer Chemical Co••. Res ," &; Devel. Dept. 

Tlli _ Eptam i a Stauffer Chemical ComPany'a tre.de~rk for el;hyldi-n-pro.pyl 

thiolc.a.I"bamate'.

422 

\lith So11 Incorporation Time of Application is Not Dependent 

Upon PlantIng Schedules: 

By incorporating EPTC into the soil seasonal weed ,.control is 

obcained. Whether or not seeding is done immediately followin6 

application control is obtained for the growing season. 

Soil Incorporation Minimizes the Need for Special CUltivaclon 

Practices: 

When the entire Boil area is treated with a soil Lncorpor'atd.on 

technique untreated soil is not moved into the crop row during 

normal cultivation practices. 

seedlinf Weed Growth is Eliminated During SOi.l Incorporation 

Appllca ions: 

Certain selective herbicides are effective o~ly prior to weed 

emergence necessitating that seedlings present at time of application 

be destroyed by some means other than the chemical being 

applied. With incorporation ot the herbicide these weed seedlings 

are automatically eliminated. 

At the present time many fertilizers and soil insecticides are 

applied to the soil surface and worked in prior to seeding. By 

combining an herbicide with these materials simplicity and economy 

of farming operations may be obtained. 

Soil incorporation techniques which have been used successfully 

with EPTC ~nfield applications and which can probably be used 

with other herbicides are: 

Preplant Soil Incorporation: 

A.) Incorporation immediately prior to seeding of tolerant crops 

has been accomplished by use of discs, spikecooth harrows, and 

rototillers. 

B.) Incorporation with delayed seeding of susceptible crops. 

Fall applications followed by spring seeding of susceptible crops 

have given weed control durirtg the crop grOWing season. 

Pre-emergence Soil Incorporation: 

This method has been used on deep seeded (2-3") tolerant. crops. 

With this method, application is made immediately following seedlng 

by incorporating to a depth of It'' by discing, spike tooth 

harrowing, or rotary hoeing in the direction of planting. 

Post-emergence Soil Incorporation

DEVELOPMENT OF FOURNEli HERBICIDES 

A. J. Tafuro l 

423 

In 1958, following extensive greenhouse trials, four new chemicals were 

given preliminary field tests to further evaluate their effec.tiveness and 

potentialities as selective or non-selective herbicides. These materials 

were sent to weed workers throughout the counky, and were also tested on 

the AmchemResearch Farm, Ambler. Pa, 

Two new benzoic acid derivatives -- 2,5-dichloro-)-nitrobenzoic acid 

(ACP1"1-460or Dinoben) and 2,5-dichloro-)-aminobenzoic acid (ACPM-629 or 

Amoben) -- show promise for pre-emergence control of weeds in various vegetable 

and field crops and crabgrass in turf. Amoben is of particular interest 

for soybeans. 

In first-year tests, a new liquid formulation of )-amino-l,2,4-triazole 

(amitrol) has appeared superior to other formulations of amitrol now on the 

market for quackgrass control. 

Formulations of 2,),6-trichlorophenylacetic acid as the water-soluble 

sodium salt (Fenac-S) or as a wettable powder of the amide (Fenac-WP) have 

produced outstanding pre-emergence control of crabgrass in turf and look 

promising for .controlling bindweed and quackgrass, and for soil sterilization. 

This material was discovered by Hooker Chemical Corporation research workers, 

and is being developed cooperatively by Hooker and AmchemProducts, Inc. 

Dinoben and Amoben 

These materials were applied to a variety of vegetables and field crops 

as an aqueous spray and in granular form for pre-emergence and post-emergence 

weed control. Pre-emergence application of Dinoben at 4 and 6 pounds per 

acre to field and sweet com produced good commercial weed control with no 

apparent permanent injury to com. Amoben showed more selectivity on soybeans 

and better weed control than Dinoben. 

TABLEI 

Response of soybeans and weeds 6-8 weeks after pre-emergence treatment 

Chemical Rate (lb/A) Weed Control Crop Injury 

Amoben 2 Good None 

Amoben 4 Good None 

Amoben 8 Excellent None 

Amoben 12 Excellent None 

Dinoben 2 Fair None 

Dinoben 4 Good Slight 

Dinoben 6 Good Moderate 

Weeds present - Barnyard grass (Echinochloa E"!sgalli), pigweed (Amaranthus 

retrofiexus), lambsquarters (Chenopodium ~), foxtail (Setaria lutescens 

and faberii), Johneon grass seedlings (~ halespensis) 

------------------------------------------------------------------------------ 

1 Research Specialist, Agr. Chem. DiV., AmchemProducts, Inc., Ambler, Pa,

424 

Table I gives observations of three field tests at rates of 2 to 6 pounds 

per acre and a logarithmic application of 12 pounds per acre downward. At 4 

pounds per acre, good commercial weed control was observed with no injury to 

the soybean crop. lunoben produced. no apparent injury at rates up to 12 pounds 

per acre, whereas Dinoben produced slight injury at 4 pounds per acre and 

moderate injury at 6 pounds per acre. 

Dinoben was the first chemical·tes'ted. ...in the greenhouse and was initially 

field tested on sandy soil in South Carolina and on muck soil in Florida. Later 

in the summer, it was tested in lkw York, Pem,sylvania, Indiana and Cal.ifornia. 

These initial tests with water as the 'carrier were applied immediately after 

planting. Test results indicated that with overhead irrigation weed control 

was good in dry areas, but in Calli'omia, whererurrow irrigation is practiced, 

Ddnoben was not effective. Carrots and peas seem to be the vegetable crops 

most tolerant of Dinoben applied pre-emergence. Other seeded crops which 

showed tolerance of pre-emergence Dinoben application were butternut squash 

and parsnips. 

TABLEII 

Response of crops and weeds'6-8 weeks after pre-E11lergence aqueous 

spray treatment with Dinoben 

Crop (Seeded) Rate (lb/A) Weed Control 

Crop In.1ury 

Upland Soil 

Muck 

Carrot 2,4,6 Good kill None None 

Tomato 2,4,6 Good kill Severe @ 4 & 6 lb/A Slight @ 4 Ib/A 

Severe @ 6 lb/A 

Lettuce 2,4,6 Good kill Severe &4 & 6 lb/A Slight @ 4 Ib/A 

Severe @ 6 lb/ A 

Cabbage 2,4,6 Good kill Severe::} 4 & 6 Ib/A 

Cucumber 2,4,6 Good kill Severe Slight e 6 & 

4 Ib/A 

Peas 2,4,6 Good kill None 

Red Beet 2,4,6 Good kill Plant killed 

-~------------------------------------------------------------------ ---- - -- - - 

'Weeds: Pigweed (Junaranthus retrofiexus and A. spinosus), larnbsquarters, 

foxtail (Setaria spp.), and crabgrass (DigitariaSanFll1inalis) 

These data indicate that crops seeded and grown on muck soil were more 

tolerant of a pre-emergence application of Dinoben than were crops on upland 

soil. Although some of these crops showed severe homone injury early, the 

plants seemed to outgrow the symptoms. 

In mid-summer of 1958, Am6benwas made and tested with Dinoben. Initial 

tests showed this material to have similar herbicidal activity to Dinoben~ but 

indicated' a longer residual control. Alriobenalso gave fair weed control when 

applied post-emergence, whereas' Dinoben was ineffective at comparable rates. 

Since aqueous sprays of both m.a.terials showed similar activity, 10%granular 

fonnulations of Dinoben and Junoben on 24-48mesh attaclay were made. Preand 

post-emergence weed control tests were applied to both RE?edAll And transplanted 

vegetable crops. .lhese data are given in Table m.

.·· . 

TABLEIII 

425 

Response of vegetable crops on two soils to pre- and post-emergence 

granular application of Amobenand Dinoben 


Crop Injury 

Crop Rate (lb/A) Control Upland Soil Muck 

-----------------.-------------_ ..•-------------------------------------------- 

Tomato 2,4,6 (Pre) Good Slight (i) 4 lb/A 

(Seeded) 2,4,6 (Post) Moderate Q 6 lb/.'!. 

Tomato 2,4,6 (Post) Good Slight 0B6 lb/ A 

(Trans.) 

Lettuce 2,4,6 (Pre) Good Slight stunting Slight 

(Seeded) 2,4,6 (Post) stunting 

Lettuce 2,4,6 (Post) Good Slight stunting Slight 

(Trans.) 

stunting 

Cabbage 2,4,6 (Post) Good' No injury 

(Trans. ) 

Caulinower 2,4,6 (Post) Good Slight @ 6 lb/A 

(Trans.) 

Heeds: Crabgrass, pigweed, lambsquarters and foxtail 

Results similar to those stated in Table III were observed on transplants 

such as pepper, Brussels sprouts, eggplant and broccoli. (All applications 

were made post-emergence to the crop and pre-emergence to the weeds.) Dinoben 

and Amoben showed similar action when applied in granular form. Little or no 

crop injury was observed; probably foliage absorption is not a factor with 

granular formulations as it is with sprays. 

Preliminary greenhouse and field tests with Amobenindicate it to be a 

promising herbicide for soybeans. Dinoben and Amoben are promising herbicides 

for post-emergence application in granular form to some transplanted vegetable 

crops. Dinoben looks promising for pre-emergence app;Lication to seeded crops 

such as carrots, peas, butternut squash, and parsnip. 

The performance of Pinoben for crabgrass control in turf is being reported 

to this conference in' another paper. Test data comparing rates of application, 

number of treatments and treatment intervals indicate that two or three treatments 

of 8 to 10 pounds per acre at 4-week intervals gave consistently satisfactory 

control (above 75per cent). 

LiqUid Formulation 

of Amitrol 

The new liquid formulation of amitrol was given extensive trials for control 

of quackgrass (Agropyron repens). In three spring tests, quackgrass 6 to 

8 inches tall was treated, plowed under, and the area planted to field corn. 

A logarithmic test was applied in early summer to regrowth of quackgrass that

426 

had been plowed in the 

spring. 

Results showed that liquid amitrol was at least twice as active on quackgrass 

as the present formulation, and as safe to use when plowing and planting 

corn followed two weeks after application. Four pounds of liquid amitrol was 

equivalent in control of quackg:rass to 8 pounds active of dalapon or 16,'P9\IDds 

of •Teedazol (8 pounds amitrol) • In no case' was corn injured when planted two 

weeks after an application of liquid amitrol, whereas dalapon did produce 

moderate injury to corn planted two weeks after application. 

TABLEIV 

------_.--~----------------------------------------~-~ - - - - - - - - - - - - - - - - - - - - - - - 

Chemical ' Rate Quackgrass Control· Corn InjUry 

~.------------------------------------------------..-----~------------~------- 

Liquid amitrol 2" 60%' '. None 

4 90+ None 

Weedazol 

(50%dry amitrol) 

4 8 

65-70 

85-90 

None 

None 

Dalapon 8 86-85 Slight to 

Moderate 

, Initial tests in California and the East indicate liquid amitrol to be 

twice as effective as :~eedazol on stoloniferous grasses such as quackgrass, 

Bermuda grass, and seaside bentgrass. Work is now in progress to discover 

whether or not this actin ty holds true on perennial weeds such as Canada 

thistle (Cirsium arvense), whitetop (Cardaria draba), cattails (TYRhS latifolia), 

tules (scirpus acutus), ete. Plots were sprayed1ii the summer of 19 8. Initial 

observations indicated liquid amitrol gave a quicker topkill of· these perennial 

weeds than Weedazoldid. Final evaluatitlns on regrowth will be made in 1959. 

Fenac is very promising for pre-emergence. crabgrass control in established 

turf, for quackgrass and bindweed control, for pre-Sllergence control of annual 

grasses and broadleaf weeds in com, and for soil sterilization. 

Extensive tests involving replicated application of eleven crabgrass killer 

formulations at different rates and time intervals to over 350 plots were 

carried out from l1pril 3> to June 26, 1958. Final observations on August 28 

showed that Fenac-Sand Fenac-NP were the most promising. Single applications 

of 3 pounds per acre produced 85 per cent crabgrass control with no turf injury. 

Six pounds per acre produced 97 per cent crabgrass controlw1th only slight 

temporary turf discoloration. 

Quackgrass control tests with Fenac were applied in Niagara County, New 

York, and at State College, Pennsylvania. In one trial in Niagara County, a 

dense quackgrass sod was 'treated July 2, 1957, at rates of 1, 2, 4 and 8 pounds' 

per acre. On ~uly7, 1957, the plots were plowed and disced. Field and sweet 

corn were planted the next day. When the plota were inspected September 10, 

1957, the 2, 4, and 8 pounds rates showed good quackgrass control, along with 

good control of aIllmal grasses and broadleaf weeds. The 1 pound rate gave

427 

only partial quaclcgrass control. Although no yield study was made, neither 

the field nor sweet eom showed apparent i..'ljury at· the 2 pound rate. The!' 

4 pound rate produced sOllIecom injury-, and the 8 pound rate produced severe 

injury-. 

In the spring of 1958, half of each plot was plowed, disced and planted 

to sweet com. The other half of each plot was undisturbed. The 8 pound rate, 

both plowed and undisturbed, continued to give complete control of quackgrass. 

There was no visible damage to the com at maturity. At the 4 pound rate, only 

partial control ot quackgrass was observed during the seoond season. 

At State Co::.J.ege, Pennsylvania, a logarithmic sprayer application of Fenac 

was made to quackgrass. This was a cooperative ElllPeriroent between Dr. S. M. 

Raleigh, AmchemProducts, Inc., and Hooker Chemical Corporation. Chemicals 

were applied to 12-foot-wide plots in 25 gallons of solution per acre. .Two 

weeks after the April 30, 1958 treatment, the area was plowed and planted to 

corn. The half-dosage distance was calculated at 21.6 feet. Quackgrass shoot 

counts were made on October 31, 19.58, following periodic observations during 

the growing season. The counts were made at the half-dosage distance and the 

rates recorded are therefore approximate. Each treatment was replicated three 

tlroes., The degree of quackgrass control is given in Table V. 

TABLEV 

Quackgrass Control 

Approx1roate Rate 

Treatment 16 Ib/A 8 Ib/A 4 Ib/A 2 lb/A 1 Ib/A o.sIb/A 

------------------------------------------------------------------------------ 

Fenac-8 96.7% 95.3% 86.!l% 84.5% 82.2% 

Benzac 354 * 49.0 68.0 35.8 13.9 8.6 

Dalapon 60.0% 71.9 40.2 42.5 0.0 

* Amine salt fonnulation of polychlorinated benzoic acid 

Fenac-S injured corn at a rate between 8 and 4 pounds per acre, although 

the 4 pound rate injury did not appear to reduce yields. No com injury- was 

observed below 4 pounds per acre, and the persistent nature ot the compoun4 

resulted in excellent control of annual weeds do~ to 2 pounds per acre. 

Below 2 pounds pez- acr.'h there was a marked suppression of size and number 

of annual weeds. The 2 pounds per' acre zone showed' annual weed control 

similar to that obtained with 2 pounds per acra of .m.azin in other areas. 

The quackgrass plants counted in the Fenac-S plots were stunted and malformed. 

No com injury- was observed in the Benzac 354 plots. (In 1957, however, com 

was damaged by Benzac 3.54 treatments.) Because of. the short time interval 

between treatment md planting, dalapon caused marked injury in the 16, 8 and 

4 pountls per acre zones.. 

These data indicate that quackgrasa ro~ be controlled by spring applications 

ot 1 to 4 pounds of Fenac-8. Safe planting of corn at various time intervals 

after treatment seems possible. Response of quackgrass to fall application 

of Fenac-S, with or without plowing, has not been detennined" nor has

4~a 

the per81l1tence ot low rates ot Fenac-5 and its l1kel:ihood of dlmaging cl'CpS 

following com in the rotation. 

In one test of 2 pounds per acre, Fenac-Swas applied pre-emergence to 

field corn.Application was Ill.ade:immediately atter planting. Weed control 

in this plot was excellent and comparable to 2 pounds per acre ot S:1Jllallin. 

There was no apparent injury to the com throughout the season and although 

711'1dsw:ere not taken, no apparent injury to the ears at corn was noticed. 

This treatltent controlled both annual grasses and broadleat weeds for a period 

of at le!1st 8 weeks. 

Although Fenac...s appears to be considerably more effective in eradicating 

bindweed*than pol,1Chlorobenzoic acid or 2,3,6-tricblorobenzoic acid (2,3,6-TBA) 

are, its actiClll 18 considerably slower. Prelimina17 tests ind1cate that fall 

applications ot S to 10 pounds of P'enac..s per acre can prevent emergence ot 

bindweed the tollow1ng spring, whereas spring applications of 8S much as 20 

pounds per acre have sOIIl.etimestailed to give complete eradication by' fall. 

The rate of action appears to be related to tbe .aunt of rainf'all. Where 

l\eavy rainf'all occurred illlmediately atter spring application, Fenac..s produced 

90 to 100%tcpldll within two weeks when applied at 8 pouJld.sper acre. Under 

dryer conditions, rates as high as 10 and 20 pounds per acre gave only 25%con... 

trol atter a month, and only 90%control after f'ive months. 

Fenac-\\!' appears to be E!lower act1ng than Fenac..s. Even though mois1ure 

is sufficient, Fenac...wFwiU take from threei;oeb:months after application 

to prowce satisf'acto1"1 control. 

PrOlll1sing results were observed when Fene.c W$S used in cOl1lbination nth 

2,!l...r>and related compounds. In two trials conducted wring the 1958 season, 

under wet soll conditions, 1 pound of 2,4..D per acre gave rapid tcpldll of 

b:lndweed in June, but heavy regrowth was observed by October. Jln application 

of 5 pounds of' Fenac..s plus 1 pound of 2,4-Dgave equally rapid topk1ll but 

there was no regrowth in October. The use of combinat1oJl.s under different 

climatic and soU conditions, particularly in earlT spring and mid-sUJlllller 

applications has not yet been inves~igated. 

Preliminary trials of Fenac..s and Fenac-WP'for complete vegetation control 

were also carried out. In the southern part ot the United States, rates of 1, 

2, 4, 8, and 16 pounds per acrewere awlied in Mev19S8, to heavy vegetation 

consisting of anml&1 broadleat and grass species, ferne, perem1al gruses, 

honeysuckle (Lonloera ~lca), locust (l.ob1n1a pseudoacacia), sumac (Bhus 

spp.), sassa&; (S88S- i!bidulil), ete. These plots were observed ed data 

taleen in August, l~. one poundper aore of Penac was too low, and did not 

give good weed control. At the 2 pOund rate, good control of broadleaf weeds 

and annual grasses and severe injury to the terns and sedge-grass (Anf2oson 

v1rginicus). was observed. At the 4 pound rate, thel'e was gcodcdntroo 

sedge-graBS', 81U1lUl,1 grasses andbroadleat weeds, !Il'ld severe inh1bit1ono£ 

locust, sumac, and sassafras; Poneywckle was killed. At rates of 8 pounds 

per acre, all vegetation was Idlled, except for some brusb species, which 

were injured. To date, no live vegetation has appeared in the 16 pound area. 

CoDlbination of 4 pounds of Fenac-S and 200 pounds of sodium chlorate per acre 

gave good general vegetation oontrol and appears to be as etfective as 16 pounds 

ot Fenac-S alone. 

* (Convolvulus arvensis)

429 

~esting for long-term soil sterilization, the Fenac herbicides were 

applied in December 1956, in the northeastern United States to a heavy clay 

soil. Vegetation consisted of annual grasses and broadleaf weeds l wild 

carrot (Daucus carota) and wild strawberry (Fragaria virginiana). Little 

difference in results was observed throughout 1957, as well as throughout 

the 1958 growing season. Fenac-HP at 8 pounds per acre gave substantially 

100% control with about 95% control of wild carrot. Fenac-S gave pl"or control 

at 8 pounds, but was effective at the 16 pound level. The least favorable 

results observed to date on long-term soil sterilization were obtained 

on a heavy clay soil which was plowed and disced before mid-summer 1957 application. 

Inspections one year later showed the following rates of Fenac 

herbicides necessary for complete control. 

Fenac-S 

(1) 

(2) 

(J) 

Fenac-HP 

(ry 

(2) 

0) 

Annual broadleaf weeds - 2i to 3 pounds 

Perennial broadleaf weeds and perennial grasses - 10 to 20 pounds 

Perennial bluegrass - 20 to 40 pounds 

Annual broadleaf weeds - under 2 pounds 

Perennial broadleaf weeds and grasses - 3 to 40 pounds 

Perennial bluegrass - 20 to 40 pounds. 

At the other extreme, Fenac-\JP was applied at 6 pounds per acre in 

September 1957, on a sandy area containing annual grasses and broadleaf 

weeds and perennials including wild carrot. The treated area remained completely 

bare of vegetation throughout 1958 with sharp boundary lines along 

adjacent heavily infested control plots. 

These four nciv materials are promising herbicides and will be evaluated 

further' in 1959. The data indicate new tools for quackgrass control, weed 

control in corn, soybean, vegetable crops and a new material for total vegetation 

control. Liberal supplies of these chemicals will be available for 

extensive trials in 1959.

430 

STATUSOF SPRAYING 

A Summary of Six Years of Spraying for Weed and Insect Control in Vermont 

T. R. Flanagan 1 

SPRAYING 

From 1953 through 1958, we kept track of the acreage of the' various cr6p~' 

sprayed and the numbers of low-pressure, low-volume sprayers in use. Figure 2 

shows how the use of spraying has increased each year. No record exists of 

farmer use of 2,4-D in the state before the early 1950 1s, however, it was used 

experimentally in 1945. vie can estimate that less than 1,000 acres of crops 

were sprayed with ar.y chemicals before 1952. 

lAssistant Agronomist, University of Vermont, Burlington, Vermont

I 

I 

i 

I 

-;» 

.'..j 

CD 

FIGURE1 

VERMONT IANDIN FARMS 

:~/ ...... ) I ',. 

.' l' \('1-" ;"fJ' / 

l, I) (IJ/~, \ \"-\ l - ' ..- /- », / 

I {; \- '~'j', ~ \~~ ( . :u~~ 

- -''I I 

lather '1- -.-. I 

1-.-- 1~~76,oOO-" - _ , I 

CroPl~d idl;~QQo- _--..:- _ ~ __ } _ 

-~o~ 5 8 ,000 ""1"\ _ - _;:;~",,\- -- ) 

- -':l.o.~ 

G!!l-1Ds .....~- ---- \ 

100 , 

- '\ _J- cl'O~s U, 00 I \ 

,-' t\01't. s S,~OO Other Pasture 

'01'cn8--c

;'iost of the spraying in 1953 was for cornfield weeds with a little on 

unclerseeded oats, a fel., pasture weeds, and some brush. The following year, 

1954, saw invasions of forest and field insects, hence a tremendous increase in 

spraying. The corn acreage sprayed almost doubled; more than twice the cropland 

acreage was sprayed for weeds than the year before. It was estimated, but unreported, 

that over 10,000 acres of forest land were sprayed by air for forest 

tent caterpillars anc1gypsy moths. For the first time ground "weed sprayers" 

were also being used to combat insects. Some 450 acres were sprayed with tractor 

mounted equipment for armTwormcontrol, and several acres of forage crops for 

spittlebug and leafhopper. 

The year 1955 saw a steady increase in acreages sprayed and the advent of 

airplane spraying of cropland for insect control. In 1956, over 9,000 acres 

were sprayed, one wa;r or another. Some 200 acres l were sprayed with insecticides, 

about half of which were airplane sprayed. 

, The fifth year of the survey (1957) again saw an increase in the amount of 

spraying done. Almost 6,000 acres of corn were sprayed, over 2,500 acres of 

small grains, mostly underseeded to legumes, and more than 200 acres of pastures. 

In addition, over 600acres of potatoes, beans, and other horticultural crops 

were sprayed for weed control. Almost the entire potato acreage (some 2,500 

acres) was sprayerl for disease and insect control, as usual, but increased use 

of low-pressure, low-volume equipment was noted. 

lThe 5,000 or so acres of orchards are excluded from this report.

433 

FIGURE2 

USE OF SPRAynm IN VERMONT 

1953 - 1958 

12,000 - 

11,000 - 

10,000 - 

9,000 .. 

9049 

Insec:t 

2 

Air 

Insect 

12 8 

I 

Insect 

Other. 

.Weeds 

.3560 . 

8,000 - 

7,000 .. 

6,000 - 

8024 

T,."' ..... t. 

other 

:weeds . 

'3 047·: 

other 

.: 

Weeds 

. Other 4016· 

Heeds 

3685 

5,000 - 

4,000 - 

3,000 .. 

2,000 - 

1,000 - 

o - 

1953 1954 1955 1956 1957 1958 

Annual total acreage sprayed for weed and insect control by low-pressure, lowvolume 

ground sprayers, and by air. Orchards, and high-pressure, high-volume 

potato spraying excluded. 

., 

':., 

'> 

'" 

Corn 

4905 

\ 

.'" 

.:,: 

.,:,(

434 

Over 1,600 acres of cropland were sprayed for insect control in 1951, about 

half by air and more than half by tractor-mounted sprayers. A few acres of corn 

were also weed-sprayed by airplane. This last year saw increases again for all 

weed spraying. The use 'of insecticides decreased slightly. 

The total acreage sprayed in Vermont climbed in just six years from less 

than' .:1.,000to over 12,000 acres. The figures for cropland sprayed each year in 

each county are listed in Table 2. Not shown ...re the numbers of lawns treated 

for weed control, an item which has been increasing each year, but difficult 

to obtain accurate figures for, nor the amount of poison ivy sprayed, nor 

brushland, fencerows, and roadsides sprayed by the farmer. 

TABLE2 - ANNUAL SID1!'lARY OFSPRAYINGIN VERMONT 1953 - 1958 

County Total acres sprayed each year* 

1953 1954 1955 1956 1957 1958 

Addison 40 611 337/1 520# 1,291,1 522/1 

Bennington 500 805 100 600 140 613 

Caledonia 300 330 510 1,190 1,180 900 

Chittenden 150 326 1,300 1,300 1,400 800 

Essex 100 430 850 660 740 418 

Franklin 100 15# 500 550 550 782 

Grand Isle 22 64 328 323 292 452 

Lamoille 76 580 275 300 1,150 819 

Orange 300 1,000 875 665 565 1,320 

Orleans 75 300 325 330 730 735 

Rutland 100 250 800 1,001 870 1,415 

Hashinp,ton 29 200 314 475 660 2,144 

Hindharn 250 500 350 610 530 400 

'/indsor 350 515 500 525 810 908 

State total 2,392 5,986 8,024 9,049 11,526 12,348 

*AIl weed and insect spraying on crops, oats, pasture, potatoes, 

beans, sweet corn, and other horticultural crops except orchards. 

#Includes both ground and air applications. 

PERCENTAGE OF LJID S~YED 

The above figures, although showing yearly gains in total acreages sprayed 

and also for the various crops treated, must be compared with the actual acreages 

of these croplands that are being farmed in Vermont. 

Table 3 shows the actual acres sprayed as percentage of total acres county 

by county, and for the state as a Whole, at the beginning of the survey for the 

best year and for last year. The acres sprayed have been compared with the 

cropland acres listed in Table 1, and the percent of the acreage actually 

sprayed calculated. Percentages are used to place counties on a fair basis 

for comparison. The acreages sprayed have increased tremendously in the last 

six years, but the percentages could be muchgreater.

435 

l'ABLE3 - PERCENTOF TOTALCPOPACF.EAGESPRAYEDFORWEEDSJl.NDINSECTS* 

B est percentage 

accomplishment 

County 1953 1958 of ideal goal. 

Addison 0.03 0.37 4 

Bennington 1.60 2.05 10 

Caledonia 0.41 1.23 7 

Chittenden 0.17 0.90 6 

Essex 0.48 2.34 25 

Franklin 0.08 0.64 3 

Grand Isle 0.08 1.73 7 

Lamoille 0.18 2.04 12 

orange 0.41 1.81 7 

Orleans 0.07 0.68 3 

Rutland 0.11 1.51 6 

Washington 0.04 3.36 13 

Windham 0.62 1.00 6 

YJindsor 0.46 1.22 5 

State total 0.24 1.24 5 

~rcentages based on acreages in Table l~ and acres 

sprayed, Table 2. 

To make the picture realistic, we have suggested a "goal of optimum 

sprayinr,", or lIideal goal". This, for total farm land, is equivalent to onefourth 

of the total acreage of all crops. The maximumarea of land we expect 

to be sprayed annually for weeds and insects would be 250,000 acres of hay, 

pasture, and cropland. Another way one could look at this is a goal Where 

every acre gets treated once in some way every four years on the average, or, 

when one out of four acres is being sprayed. 

Comparing the actual acreage sprayed against this one-quarter "ideal goal" 

we find that the state average is just 5 percent of completion. 

B 

CORNSPRAYING 

GOAL: 250,000 ACRES 

~---------I 

Let us look at Vermont's principal cultivated crop, corn. In Table 4 

census figure acres are again compared with reported data for weed spraying, 

county by county, yearly since 1953. The acreages sprayed have gradually 

increased in most counties, and the state totals show a gradual but steady 

increase in corn weed control for each year.

436 

i'ot~ 

TABLE4 - WEEDCOUTROL IN CORN~~ 

Best percentage 

Acres Acres spra~ed accomplishment 

County Corn# 1953 1954 1955 19 0 1957 1958 of ideal t goal 

Addison 10,905 35 140 130 180 95 125 3 

Bennin~;ton 2,589 500 600 600 500 600 600 46 

Caledonia 2,715 300 200 400 500 550 570 42 

Chittenden 7,555 150 225 300 300 400 550 15 

Essex 364 100 95 200 250 200 75 41 

Franklin 7,163 100 50 500 450 450 670 19 

Grand Isle 2,345 22 40 175 73 40 150 13 

Lamoille 2,210 76 300 200 250 500 755 68 

Oranrse 3,329 300 800 600 500 400 550 33 

Orleans 3,653 75 200 250 250 250 350 19 

Rutland 6,132 100 250 500 650 700 1,200 39 

vlashington 2,667 17 100 200 350 500 1,400 100 

Windham 2,777 250 300 350 400 400 300 22 

\riindsor 3,449 350 500 500 500 750 900 52 

State total 57,8S3 2,380 3,800 4,905 5,153 5,835 8,195 28 

*Includes silage corn, grain,corn, grazed com • 

.¥Census of 1954. 

Over 8,000 acrea were sprayed in 1958. However, this is only 14 percent 

of the total corn acreage. fullY half of the 57,000 acres of corn grown annually 

in Vermont are weedy, some only moderately so. Unfortunately many fields 

are almost too weedy to be harvested. Let us establish a goal for corn where 

all of the weedy fields are sprayed. Thus, there are 25,000 to 30,000 acres of 

corn which could and should benefit from chemical weed control. Howwell we 

have done to date is shown below. 

GOAL: 28,500 ACRES 

As we can see, 14 percent of the total corn acreage, or 28 percent of this 

separate goal for corn .Teed spraying has been accomp'lLshed, Spraying corn 

should and can be the most probable weed control effort that will show immediate 

economic gains for the Vermont farmer. vJeeds in the cornfield cost money. 

SHALLGRAINSPRAYING 

Table 5 gives a picture of the weed spraying work done on oats and other 

small grains. It is a picture somewhat different from that for corn. Acreages 

sprayed have increased over the five-year period of the survey but not consistently. 

Possibly more acres are sprayed than reported.

437 

TABLE5 - WEEDCONTROL IN SEALLGFlAINS* 

Total 

acres 

Acres Sprayed 

County grain# 1953 1954 1955 1956 1957 1958 

Addison 7,437 + 45 35 55 5 

Bennington 1,572 + 100 100 100 50 50 .! 

Caledonia 1,996 + 90 ~.SO 160 100 120 

Chittenden 3,835 100 1,000 1,000 1,000 85 

Essex 513 + 122 400 300 400 200 

Franklin 7,072 + 25 0 100 100 110 

Grand Isle 1,654 + 20 150 250 250 275 

Lamoille 786 + 50 50 50 75 60 

Oran!§.e 1,789 + 200 125 75 125 120 

Orleans 4,292 + 75 75 75 90 100 

Rutland 2,482 + - 300 350 150 200 

WashLl'lgton 1,316 12 75 100 100 100 700 

Windham 546 + 100 300 200 100 0 

1Ilindsor 1,086 + 15 0 25 25 0 

State total 36,376 132 1,017 2,785 2,840 2,565 2,025 

*Includes grain grown together and threshed as a mixture, oats threshed 

or combined, other grain threshed or combined, and small grains cut for 

hay. #CensUBof 1954 +Approximately 10 acres -no report 

About half of the small grain fields concerned are underseeded to grasslegume 

mixtures resulting in hay or improved pasture lands of several years' 

duration. These should be economically important to the farmer, and be treated 

for weed control. However, with presently available spray materials such acreages 

will probably be sprayed, on the average, one year out of four. On the 

other hand, good hayland can be profitably treated for insect control, which 

could conceivably be on an annual basis. 

A goal of one-fourth the small grain acreage to be sprayed is then not too 

far out of line. About 22 percent of such a goal was averaged last year. 

22% GOAL: 9,000 ACRES 

Such a goal is not too much to expect for the future. v!ith the anticipated 

advent of safer chemicals and those more efficient for direct use on 

seedings, better legume and grass stands can be established than ever before. 

HAY AND PASTURE 

Accurate figures for hayland and pasture land sprayed for weed or insect 

control do not exist. Since such lands are involved in the large blocks of 

relatively extensively farmed hay and pastured cropland (Figure 1) it might be 

well to assume such fields would be treated, on the average, no more often than 

..... - _- _ -~ ~_ _ u _ _ ~""_ 'A lo. _+ _4' ,...'_ " ,.._~, _OP I)C

Hay and pasture spraying can take many forms, from insecticides, general 

broadleaf weed control, spot spraying of thistles and milkweed, brush patch 

eradication, to land renovation, quackgrass control for pre-crop planting, and 

even the possibility of fungicides and hay preservatives. Such will be contributions 

to the over-all goal of 250,000 acres treate0 annual~ for weeds, 

insects, ..and disease. 

USEOFSPRAYERS 

The numbers of low-pressure l~l-volume sprayers were counted annually. 

The numbers of such spray rigs in use in 1958 are listed in Table 6. From only 

a handful (less than 30 in 1952), these have increased in number to over 200. 

Last year 212 sprayers were in operation. This figure includes all types from 

boomless to tractor-mounted boom-type rigs. In addition, about 13 commercial 

outfits are being operated. Also not counted in this total is a half' dozen 

airplanes and helicopters spraying brush and forage insect control by contract. 

Over 70 of the farmers owning weed sprayers did some custom work. 

TABLE6 - PERCENTOFFARMERSCWNINGTRACTORS THAT"HA VESPRAYRIGS 

Percent of 

Numberof Numberof Numberof tractor owners 

County tractor owners* sprayers 1953 sprayers 1958 having sprayers 

Addison 1,118 2 12 1.1 

Bennington 484 4 10 2.1 

Caledonia 701 2 13 1.8 

Chittenden 882 2 25 2.8 

Essex 166 3 4 2.4 

Franklin 1,158 2 9 0.8 

Grand Isle 245 1 10 4.1 

Lamoille 515 1 11 2.1 

Orange 949 0 25 2.6 

Orleans 1,037 4 20 1.9 

Rutland 963 3 20 2.1 

Washington 648 3 25 3.8 

tiindham 650 6 10 1.5 

Windsor 1,089 6 18 1.6 

State total 10,120 39 212 2.1 

~4 Agricultural Census data for farmers owning one or more tractors. 

Here also a similar situation exists, akin to the corn spray picture. 

Over 10,000 farmers in Vermont own one or more tractors. Only a little lUore 

than 2 percent of these tractor owners have sprayers. Many more could and 

should be so equipped at a likely profit to themselves and a gain in weed 

control efforts for the state. 

ACRE SPRAYEDPERRIG 

It might be conceivable that with the steady increase in numbers of

439 

sprayers that the use of each sprayer would diminish. However, the reports are 

to the contrary. In 1953, atout 39 acres Were sprayed by each operator. In 

1958, the state average increased to 58acres of weed and insect control per 

spray rig (Table 7). Many counties did better than this. 

TABLE7 - ACRESOFCROPIANDSPRAYEDPERRIG 

Possible net Possible 

profits per net per 

Acres rig at $lS0 rig with 

County 195j 1958 net/A 1958 goal* 

Adc'tison 13 36 $ 54.00 $189 

Bennington 71 67 100.50 102 

Caledonia 50 69 103So 156 

Chittenden 33 32 48.00 150 

Essex 33 119 178.50 186 

Franklin 11 87 13OSO 159 

Grand Isle 76 45 67.50 160 

Lamoille 300 74 111.00 117 

Orange 75 53 79.50 116 

Orleans 25 37 55.50 156 

Rutland 33 71 106.50 146 

Washington 10 86 129.00 147 

~·Jindham 36 40 60.00 93 

Windsor 50 50 75.00 102 

State total 39 58 $ 87.00 $147 

iGOal: i of tractor-owner farmers having sprayers and 

spraying t of total farm land acreage (Table 1). 

It is interesting to note that at an estimated net profit for custom work 

of $1.50 per acre, the average gain to the owner of a sprayer in 1958was $87.00 

(Table 7). Hany operators, judging by the county figures, did better than this. 

If we set up a goal of one-fourth of the farmers spraying one-fourth of the 

cropland acreage, the average net profit per spray rig could be almost ~150 per 

year. These net gains were calculated over and above all costs of operation, 

labor, materials, and depreciation over a 10 year period. Ignoring depreciation 

it would conceivably be possible to buy a $300 low-pressure, low-volume sprayer 

and pay for it by two years of custom operation. 

INFORYJATION 

To provide impetus to Vermont's spray program considerable use has been 

made of farmer meetings and of the newspaper, radio, and television. Brieflets, 

'-" pamphlets, a periodic weed spray bulletin to county agents - "Spray Tips", and 

annual \veed Control Recommendation Charts have been widelY' distributed. Local 

"" __ \0,.'; -.';A,... A ......,,' ....._e ha ........ e.1 eo"",.."Y"l.+_ .... 04....n+..o.~ +.1"\+.ht) ;n""""A!:Ii!r::tina !r::tnr">-I":A!=I~ nf TJ~Arl anrl

4'..0. 

TEMPERATURE, LIGHT, ANDSEEDSIZE ANDTHEIR EFFECTSON 

GERMINATIONOF DOGFENNEL 

R. D. Ilnicki 

l 

and M. W. Johnson 2 

ABSTRACT 

Dog fennel (Anthems cotula), is classified as a winter 

annual and sometimes as an annual. This weed causes serious 

losses in small grain production and is also a pest in other 

crops and pastures in the Northeastern states. Dog fennel 

seeds apparently germinate throughout most of the growing 

season. These extensive germination periods increase the 

difficulty of developing control practices. In order to 

obtain good control of this species by the proper timing of 

herbicidal chemicals, it is imperative to know when dog 

fennel seeds germinate and what factors enhance germination. 

Seeds of dog fennel were introduced into thermostatically 

controlled dark germinators operated at 500 , 59 0 , 68 0 , 

770, 860, 950, and l04 0F. in order to determine what temperature 

regimes were most favorable for germination. Temperatures 

of 500 and 680 were most favorable for germination, 

however, many seeds failed to germinate. 

Greater numbers of seeds germinated when they were introduced 

into an alternating dark-daylight germinator operated 

at 68 0 in the dark and 86 0 F. in daylight. At this point in 

the study it was observed that only small seeds germinated. 

The relation of seed size to germination was studied. 

Two sizes were made by screening seed through a 6 x 24 mesh 

screen. Seed that p~ssed through were called smallj the ones 

retained were called large. These two sizes or seed were introduced 

into dark-daylight germinators. Many more small 

seeds than large ones germinated. Large seeds germinated when 

their seedcoats were removed. This behavior is contrary to 

the late germinating small, hard seeds of legumes. 

The first seed supply was made on the College Farm Campus. 

An additional seed harvest was made near Jamesburg, N. J. in 

order to determine whether this peculiar characteristic of 

seed size was typical of all dog fennel seed. Similar data were 

obtained with the new seed harvest. 

Additional seedings made in pots, in the greenhouse and 

out-or-doors, and in field plots inQicated that the marked 

difference in germination percenteges of large and small seeds 

is a characteristic of this species. 

lResearch Agronomist, Crops Research Division, ARS, USDA, 

in cooperation with the New Jersey Agrioultural Experiment 

Station, Rutgers-the State University, New Brunswick, N. J. 

2Seed Analyst, New Jersey Agricultural Experiment Station, 

Rutgers-the state University. New Brunswiok. N. J.

*Authorized for publication on December 1, 1958, as paper No. 2322 in 

the journal series of the Pennsylvania Agricultural Experiment Station. 

Quackgrass Control* 

S. M. Raleigh 

Penn State University 

441 

It is relatively easy to control 85-95% of the quackgrass by chemicals 

when compared with non-treated checks. Some of the 5-15% of the 

plants which were not controlled, come from seed. The control of 

quackgrass is influenced by cultural methods. We achieved better control 

on the lower slopes of a fi.eld where the plow turned the furrow 

down the hill, than where the furrow was turned up the hill. Control 

was poorest where the soil was hard to plow and cultivate. 

Since Dalapon must be handled in a diffe£cnt manner than amino 

triazole, two experiments were set up for dE.1apon, and two tests 

handled for the benefit of amlno,triazole •. 

Thefirst dalaponplot8 were 6 rows wide and 150 feet long. They 

were sprayed April 14. The second plots were sprayed April 23, and 

the last on April 30. The plots were all plowed May 1st and 2nd and 

planted May 23 to corn. 

spray date, The results 

The best control 

were: 3.3/;,80%; 

was obtained 

66/;,89%; 

with Ap~il 23 

11.1/;, 95% and 

22.211, 94%. 

The control of quackgrass on the first and last dates was about 

5 to 10%poorer than on the April 23 date. There was some injury to 

the corn crop on..all treated plots with this 2l-day interval between 

plowing and planting. 

The second,dalapon experiment was sprayed by hand using 10, 20 'and' 

40 gallons of water per acre, each with 3.3, 6.6 and 1141 pounds of 

dalapon. The plots were sprayed May 12 waen the quackgrass was about 

6-8 inches tall. There were 3 replications. There was no visible 

difference in control with the different water rates. The 10-gallon 

of water per acre plots were somewhat bTowner than the 20 or 40 gallon 

per acre plots when the sod was plowed. The control for each rate 

was; for 3.3#-67%, for 6.6#-83%; and for 11.1#-91%. There was some 

injury to the corn on all treatments early in the season. The corn 

plants on the check plots was taller than on the dalapon plots for 

about 3 weeks; later, when competition with quackgrass became severe 

the corn on the check plots were smaller taan the treated plots. 

Greenhouse tests by AmchemProducts, Inc. last winter indicated 

that amino triazole activity could be increased by combinations 

of 2 or more herbicides so 69 plots were sprayed in the field with 

a "log" sprayer in the spring of 1958. The applications were made 

April 28-30 when the quackgrass was 4-6 inches tall, plowed May l5.'" 

and planted May 16. The treatments were 1, 2 and M;amino triazole 

respectively, with 12# ACP 604 (PCPE), 12# ACP605 (PCNA)and 12# 

ACP655; 2# amino triazole with 12# Ammate, 12# thiourea, 12# ACP354 

(PCB) and 4/1 dinitro, respectively. In each case, the last material 

was "logged". 81; fenac (2,36 trichlorophenylacetic, Na salt) 16# 

dalapon and 4# dalapon with 8# ACP569 logged. 

, . 

.... '\. 

I ., 

, '. ~} 

.,

442 

The addition of compounds 604, 605 and 655 increased the activity 

of amino triazole at the lower rates (1-2 pounds); but at the 12# of 

these compounds rates there was no benefit. The addition of ~mate, 

thiourea and dinitro had no beneficial effect on action of amino triazole 

at any of the rates tried. Liquid amino triazole controlled 

quackgrass at rates down to 2 pounds per acre. 

Fenac is an efficient compound, when applied to quackgrass 4-6 

inches tall, treated areas allowed to stand 2 weeks, then 'plowed and 

planted •. All·gTcwth including corn, was killed by this material at 

the rate of 8 lbs. 

There was little injury to corn at the 4# rate and lower levels •. 

Quackgrass was controlled at 1,or 2 pounds per acre. 

In another experiment, (table 1) twenty-one treatments with 4 

replications each were applied May 8 to quackgrass 5-7 inches tall. 

The plots were plowed and planted May 27. Four plots in each replication 

had been treated with 50# of N April 17. There were 5 plots 

in the second replication where the control was rated rather low, 

(70% control); there were 6.6# of dalapon and 4# ACP354 with and without 

nitrogen, and ACP569. The average control is given in table 1. 

Areas where 2, 4 and 8 pounds of amino triazole was applied to 

quackgrass were treated with 1 and 2 pounds of Simazin and 2,4D ester 

at planting and at emergence. In no case was there injury to the corn 

and in no case was there any improvement in quackgrass control over 

that achieved with amino triazole alone. 

In summarv, it is necessary to wait 4 weeks after plowing before 

planting corn where dalapon has been applied. 

Cultivat.ion of corn is helpful and desirable where quackgrass 

control has been applied. It is essential with spring applications 

of amino triazole. 

Where amino triazole is used, sfter waiting 2 weeks after herbicide 

is applied it is desirable to plow, prepare the seedbed and plant 

corn the day of plowing.

443 

Table 1. Percentage Quackgrass Control in Relation to Cultivated Check. 

Rate in pounds 

per acre Treatment %Control 

2 Amino triazole 92 

4 94 

4 ~ 501FNitrogen 88 

8 " " 91 

II 

2 " 

.;. 141ACP604 94 

II 1/ 

2 I- 2il ACP604 93 

2 

,. II 

.;. lIF ACP605 94 

1/ 

2 " 

~ 1/1ACP655 97 

1 Liquid amino triazole ACP569 84 

II 

1/ 

2 " 

ACP569 94 

6.6 Dalapon 85 

II 

6.6 ~ 50/1 Nitrogen 84 

11,1 " 89 

4 S1mazin 87 

4 " I- 501FNitrogen 85 

8 

1/ 

94 

4 ACP354 86 

4 ACP354 .;. 50# Nitrogen 88 

8 ACP 354 96 

4 Fenac 89 

8 

tI 

96

444 

Effect of Soil Reaction, Moisture, and Fertility on the 

Response of Northern Nutgrass to Monuron 

R. S. Bell, E. J. Bannister, Jr. and T. Tisdel1 2 

When the northeastern regional weed control project to study 

the influence of environmental factors on the effectiveness of 

herbicides was activated, a greenhouse study with monuron, (3 

(p-chlorophenyl)-l, l-dimethylurea) and northern nutgrass (Cyperus 

esculentus L.) was begun at the Rhode Island Agricultural Experiment 

Station, supported in part by the regional project, N,E. 12. 

The purpose of this investigation was to determine whether variations 

in soil moisture, soil acidity, and fertility affected the 

herbicidal and residual toxicity of this herbicide. 

Hill anc his co-workers (2) published an extensive report 

on the fate of substituted Urea herbicides in soil. They found 

that the toxicity of 1 to 2 pounds of chemical per acre disappeared 

in 4 to 8 months. Loss by leaching was not a major factor 

under field conditions, Some decomposition by light was ,possible 

where the material remained on dry soil. They concluded that the 

loss of substituted ureas was principally due to microbial activity. 

Loustalot and co-workers (3) showed that high temperatures 

and moisture facilitated. the loss of monuron. Rahn (4) found 

less monuron with an oat bioassay test than by chemical tests, 

which suggested that non-toxic degradation products were present. 

Sherburne, Freed and Fang (5) determined that the leaching 

of monuron increased with increasing water percolation. Leaching 

was greater from a sandy than from a clay loam soil. 

Field tests in Rhode Island (1) showed that 10 pounds per 

acre of monuron reduced markedly the numbers of nutgrass plants 

but its residual toxicity lasted for several months. 

Upchurch (6) working with diuron found that this material 

produced plants having nearly equal amounts of growth under all 

soil moisture levels. This indicated that moisture had no absolute 

effect but a large relative effect on the phytotoxic 

properties of diuron. 

Materials 

and Methods 

The investioation was conducted in a greenhouse during the 

winter of 1955-56 and 1956-57. Soil having pH levels of 5, 6, and 

7 was prepared. The original pH of the Bridgehampton silt loam

445 

was 5. Calcium hydroxide was used to produce pH 6 and '1. The 

fertility was supplied with a soluble fertilizer with a 19-28-14 

guaranteed analysis applied at rates of 250 and 500 pounds per 

acre for each pH level. 

The source of monuron was Karmex \IT (80% active). The rates 

of Karmex Wused were: none. 2~, and 5 pounds per acre, respectively. 

The herbi"ide was suspended in water and applied to the 

soil surface. 

Sufficient numbers of pots were used so that the effect of 

monuron, pH, and fertility could be tested at 2 moisture levels, 

35-50%, and 80-100% available. The soil was placed in 6-inch 

pots. Six 6-inch clay pots were used for each treatment. 

Nutlets gathered from a nearby potato field in October 

were started in flats of soil in a warm greenhouse. When 2 

inches high, three uniform plants were transplanted into each 

pot. Incandescent lights were used from transplanting until 

January 1 to afford a 16 hour day, which favored top growth. 

They were grown with normal daylight during January to promote 

nutlet formation. Yields were taken in early February, after 

which ~ats were planted frbm time to time i~ these pots to 

test for the residual toxicity of monuron. Harvesting of the 

nutlets brought about a mixing of the herbicide through the 

soil. 

Results 


Several visual toxicity symptoms appeared on the nutgrass 

10 days to 2 weeks after the application of monuron. There was 

a yellowing or browning of the leaf tips, a collapse of the 

leaf sheath sufficient to allow the blades to droop, and some 

sticking together of the tips of new blades. A small amount 

of pitting was found along the veins. 

Dry weight 

of tops, 

The average oven dry weights of nutgrass tops in grams 

per pot are shown in table 1. The total average yields for the 

0, 2~, and 5 pounds per acre of Karmex W were 1.06, 0.73, and 

0.55 grams in 1956, and 1.87, 0.97, 0.71, respectively, for 

1957. This amounts to an average decrease in yields of 22 and 

49 percent in 1956 and 49 and 63 percent respectively, in 1957. 

These data show that the toxicity of the monuron in Karmex W 

is of such magnitude that the effects of soil reaction, soil 

moisture and fertility are of little consequence. 

In 1956 no differences in yields of tops were attributable 

to pH variations. In 1957, as is fairly commonin plant 

tests where complete control .of environmental factors is not 

attained, the yields of tops from the check plots were s~mewhat 

greater at pH 5. Again, however, at 2~ and 5 pound per 

acre, respectively? no significant difference in yields were 

ft'lllnrl ft'lT' th ... +.h,..",... nH l",vl'll s ;

) ) 

Table 1. Avera

447 

Each year both high fertility and moisture promoted significant 

increases in yields of nutgrass tops from the untreated 

soil. The yields were significantly reduced in direct proportion 

to the amount of monuron added. In 1956 in the presence of monurcn 

the yields of nutarass were similzr at both low and high moisture 

levels. However, win 1957, a significantly lower yield was obtained 

from the interaction of 5 pounds of Karmex Wand high moisture. 

Monuron nullified the favorable effect of adequate fertility and 

moisture. 

Green weight of nutlets. 

The total average green weights of nutlets in grams per pot 

are shown in table 2. They were 4.04, 0.89, 0.08 grams for 1956, 

and 5.01, 0.85, and 0.24 in 1957 for 0, 2~, and 5 pounds of Karmex 

W per acre. This amounts to an average decrease in yield of 78 

and 98 percent in 1956 and 83 and 94 percent in 1957. Monuron 

caused a greater percentage reduction in nutlet production than 

in top growth. 

Yields of nutlets from the check plots were significantly 

greater at high moisture and fertility. The soil reaction made 

no significant difference to the check in 1956 but in 1957 yields 

of nutlets were higher at pH 6. A study of the interactions shows· 

a direct depression of the growth by increasing amounts of Karmex 

W. Variations of interactions of this herbicide with pH, moisture, 

or fertility fo= the 2-year per~od showed that these variables ' 

were of little consequence compaFed to the effect of monuron. At 

the 2~ pound per acre rate of Karmex W, the yield of nutlets was 

significantly higher at the higher moisture content in 1956'but . 

significantly lower in 1957. Since less top growth was produced 

in 1957 by the high moisture + Karmex W combinations, it is likely 

that the lowered yield of nutlets is also related to the reduced 

growth of nutgrass tops. 

Residual 

tOXicity •. 

In the residual toxicity tests oats grew better at pH 6 or 

7 than at 5. Th~ monuron toxicity was first shown by whitening 

of the tops of the lowest leaves, followed by reduced growth or 

death of the plant. In 1956 the toxicity of monuron was reduced 

more qUickly in the pots of soil at pH 6 or 7 and high moisture 

content. In the dry soil ~hese differences did not occur. In 

1957 low acidity and high moisture did not produce this effect. 

One possible explanation is that in 1956 a microbial population 

may have developed in the less acid, moist soil which favored a 

more rapid degradation of the monuron. New soil was brought in 

for the 1957 tests so there was no microbial carry-over from the 

previous year. Hill and co-workers (2) have found that microbes 

playa definite role in the decomposition of SUbstituted urease 

In the winter of 1958 soil formerly treated with Karmex Wand 

adjusted to 3 pH levels was placed in plastic bags. Fresh soil 

'ttf~e e';",,"; 1 ::...,..1" +"".c.~+6A ~M:a1 1 ~ml"'\l1""+c:. t"l.f mnf'\11'rnn UIO""C) m;y~rI in+n

) ) 

Table 2~ Average green weight of nutlets in grams per pot 1956 and 1957. 

--------------------------------------~m~--~~~; 

Karmex W pH Level IVioisture_ Fertilizer W Percerr 

_LQ.sLA 5 6 7 ho~ __ !:!igh__ -' hbil~ _ .!:.bij~ Ay. fieQ.u£t; 

1956 

0 4.14 4.13 3.85 3.32 4.76 3.76 4.31 

212 0.92 0.75 0.99 0.65 1.13 0.76 1.02 

5 0.05 0.07 0.11 0.13 0.03 0.08 0.08 

4.04 

0.89 

0.08 

78 

98 

AV. 1. 70 1.65 1.65 1.36 1.97 1.53 1.80 

1957 

0 4.99 5.49 4.54 3.42 6.59 4.29 5.72 

212 1.22 0.78 0.57 1.11 0.60 0.83 0.88 

5 0.22 0.20 0.29 0.40 0.07 0.22 0.26 

5.01 

0.85 

0.?4 

83 

·94 

rl.V. 2.14 2.15 1.79 1.64 2.44 1. 78 2.28 

L.S.D. at 5 perce~t level. 

1Xl 

-.:t 

-.:t 

Karmex Vi 

pH 

lVioisture 

Fertility 

Karmex !Ii x pH 

Karmex W x Moisture 

Karmex W x Fertility 

1956 

0.25 

NS 

0.20 

0.18 

NS 

0.31 

0.:'\1 

1957 

0.41 

0.24 

0.33 

0.23 

0.40 

0.36 

0.36

samples of these soils during the spring and summer gave no indication 

that either pH or former applications of monuron was 

effecting the disappearance of monuron. 

C2nclusion~ 

449 

The initial toxicity of monuron is such that soil reaction, 

fertility, and moisture have no practi.cal effect on it. Karmex 

at 5 pounds to the ccre reduced top growth of nut grass by as 

much as 63 percent and nutlet production by 98 percent. undoubtedly 

under field conditions the disappearance of monuron 

from the topsoil is due to combinations of microbial decomposition 

and leaching. 

Literature 

Cii2~ 

Bell. R. S. anu Bannister, E. J., Jr. Chemical control of 

northern nutgrass in potato fields (progress report fl). 

Proc. NEWCG,p. 231-234. 1955. 

Hill, G. Do, McGahan, J. W., Baker. H. M., Finnerty, D. W. 

and Bingeman, C. W. The fate of sUbstituted urea herbicides 

in agricultural soils. Agron. Jour. 47:93-104. 

1955. 

3. Loustalot, A. J., Muzik, T. J., and Cruzado. H. J. A study 

of the persistence of CMUin soil. Agr. Chemicals 8:52-53. 

97-99, 101. 1953. 

4. Rahn, E. M., Baynard, R. I., Camp, J. F. A bioassay for CMU 

in soils. Proc. NEWCCp. 12. 1957. 

5. Sherburne, H. R•• Freed, V. H' i 

and Fang, S. C. The use of 

C14 carbonyl labeled 3-(p-ch orophenyl}-l,l-dimethyl urea 

in a leaching study. Weeds 4:50-54. 1956. 

Upchurch, n. p. The influence of soil moisture content on 

the response of cotton to herbicides. Weeds 5:112-120. 

1957.

*NATIONALAGRICULTURALCHEMICALSASSOCIATION, 

450 

SPECIFICATION OF HERBICIDE MATERIALS 

FOR PUBLIC AGENCIES 

JACK DREESSEN* 

ADEQUATESPECI~ICAT'ONS ~OR PURCHASINGVARIOUSHERBICIDE MATERIALS 

HAVENOT BEEN DEVELOPEDFOR MOSTHERBICIDES COMMONLYUSED TODAY. THIS 

LACK O~ SPECIFICATIONS HAS CREATEDPROBLEMSFOR THOSE WHOSELL THESE 

MATERIALSAS WELLAS THOSE PERSONS WHOARE RESPONSIBLE ~OR BUYING 

THESE MATERIALSFOR USE BY PUBLIC AGENCIES. 

THE FEDERALGOVERNMENT,RECOGNIZINGTHE NEED FOR PURCHASESPECIFICATIONS, 

HAS ADOPTEDAN INTERIM FEDERAL SPECI~ICATION ~OR USE BY FEDERALAGENCIES 

IN PROCURING2,4-0 ~ORMULATIONS. THIS SPECI~JCATION WASREVIEWEDBY 

SEVERALMEMBERSO~ THE AGRICULTURALCHEMICALSINDUSTRYANDMANYSUGGES 

TIONS OFFEREDBY MEMBERSOF THE INDUSTRYARE INCORPORATEDIN THE 

SPECIFICATION. 

THE INTERIM FEDERALSPECIFICATION ~OR HERBICIDE 2,4-0 IS PRESENTED 

HERE IN FULL IN THE HOPES THAT IT WILL SERVE AS A GUIDE ~OR OTHERPUBLIC 

AGENCIES. SOMECHEMISTS HAVERESERVATIONSAS TO THE ADEQUACYOF 

METHODSOF' ANALYSIS SET FORTH IN THE SPECIFICATIONS, BUT AS OF THIS TIME 

THIS SPECIFICATiON FOR 2,4-0 IS THE BEST THAT HAS BEEN DEVELOPED.

PPP-C-96 

PPP-D-723 

-CANS, METAL28 GAGEAND LLGHT~R 

-DRUMS. fIBER. 

4til 

O-H-00200 (AGR-ARS) 

AUGUST6, 1956 

INTERIM FEDERALSPECIFICATION 

HERBICIDE, 2, 4- DICHLOROPHENOXYACETIC ACIO 

(SALTS ANOESTERS) 

,·'1 

THIS INTERIMFEDERALSPECIFJCATION WASDEVELOPEDey THE AGRICUL,TURERESEARCII 

SERVICE, DEPARTMENTOF AGRICULTURE,BASEDUPONCURRENTLYAVAILABLETECHNICAL 

INFORMATION. IT IS RECOMMENDED THATFEDERALAGENCIESUSE IT IN PROCUREMENT 

ANDFORWARDRECOMMENDATIONS 

CHANGESTO THE PREPARINGACTIVITY AT THE 

ADDRESSSHOWNABOVE. 

1. SCOPE ANOCLASSIFiCATION 

1;1 SCOPE.- 2,4-0ICHLnROPHENOXYACETICACID (2,4-0) IS AN ORGANICACID 

RELATIVELYINSOLUBLEIN WATERnR niL. IT IS NORMALLYC~POUNDED BEFOREBEING 

USED AS AN HERBICIDE. 2,4-0 IS A SELECTIVE HERBICIDE. WHENAPPLIED AS A POST 

EMERGENCESPRAY IT WILL KILL MANYBRnADLEAVEDWEEDSANDWOODYPLANTS, WITH 

LITTLE OR'NO INJURY TO MANyGRASSES, SEDGES, ANDOTHERMONOCOTYLEDONOUS PLANTS. 

HOWEVER,WHENUSED AS A PRE-EMERGENCESPRAYOR AS A FOLIAGE SPRAYON SEEDLINGS 

2,4-0 CANALSO BE USED TO CONTROLMANYANNUALGRASSES. THIS SPECIFICATION 

COVERSTHREEGENERALTYPES nF 2,4-0. 

1.2 CLASSIFICATION.- FORMULATIONSOF 2,4-0 COVEREDBY THIS SPECIFICATION 

SHALLBE OF THREE GENERALTYPES AS SPECIFIEDl 

TY~E I - DRYPOWDER,SODIUMSALT, FORMSWHICHARE THE LEAST TOXIC TO 

PLANTSPER POUNDOF 2,4-0 ACID EQUIVALENT. 

TYPE 1/ - LIQUID AMINE SALT rOAMS WHICHARE INTERMEDIATEIN TOXICITY TO 

PLANTSPER POUNDOF 2,4-0 ACID EQUIVALENT. 

TYPE 1/1 - LIQUID ESTER rORMS WHICHARE THE MOSTTOXIC FORMSOr 2,4-0 Tn 

PLANTSPER POUNDOr 2,4-0 ACIOEQUIVALENT. 

CLASS 1.- VOLATILEALKYLESTER OF' 2,4-0. 

CLASS 2.- 

Low VOLATILEESTERS. 

2. APPLICABLESPEC/FICATIONS, STANDARDS,AND'OTHERPUBLICATIONS 

2.1 THE FOLLOWINGSPEClrlCATIONS ANDSTANDARDS,OF THE ISSUES IN 

En'EeT ON DATEOF INVITATION FOR BIDS. FfIIRMA PART OF TH1SSP£CIF"lCA'T10NI 

rEDERAL SPECI~I~ATIONSI

3.1 TYPE 1.- THE DRYPOWQER~ORM SHALLCONSIST OF' THE SODIUMSALT Or 

2,4-DICHLOROPHENOXYACETICACID MONOHYDRATE ANDSUCHMODIFYINGANDCONDITION- 

452 

PPP-D-729 -DRUMS: METAL, 55-GALLON 

(FOR SHIPMENTOP NON-CORROSIVEMATERIALS). 

PPP-D-760 -DRUMSANDPAILS, METAL(5 AND16.64 GALLON). 

PPP·P-31 -PRESERVATION, PACKAGING,PACKING, ANDMARKINGOP MATERIAL, 

ANDSHIPPING INSTRUCTIONS(DOMESTICSHIPMENTANDSTORAGE). 

FEDERALSTANDARD, 

FED-STD 

NO. 102 - PRESERVATION,PACKAGING,ANDPACKINGLEVELS. 

(ACTIVITIES OUTSIDE THE FEDERALGOVERNMENTMAYOBTAIN COPIES OP FEDERAL 

SPECIPICATIONS ANDSTANDARDSAS OUTLINEDUNDERGENERALINPORMATIONIN THE 

INDEXOP FEDERALSPECIF'ICATIONS ANDSTANDARDiSANDAT THE PRICES INDICATEDIN 

THE INDEX. THE INDEX, WHICHINCLUDESCUMULATIVEMONTHLYSUPPLEMENTSAS 

ISSUED, IS POR SAl.E ON A SUBiSCRIPTIONBASIS BY THE SUPERINT£NDENTOP DOCUMENTS, 

U. S. GOVERNMENTPRINTING OF'PICE, WASHINGTON25, D. C. 

(SINGLE COPIES OP THIS SPECIPICATION ANDOTHERPRODUCTSPECIPICATIONS 

REQUIREDBY ACTIVITIES OUTSIDE THE FEDERALGOVERNMENTF'ORBIDDING PURPOSES 

ARE AVAILABLEWITHOUTCHARGEAT THE GENERALSERV/CtS ADMINISTRATIONOPF'ICES 

IN BOSTON, NEWYORK, ATLANTA,CHICAGO, KANSASCITY, MO., DALLAS, DENVER,SAN 

FRANCISCO, Los ANGELES, SEATTLE, ANDWASHINGTON,D. C. 

(f"EDERALGOVERNMENTACTIVITI ES MAYOBTAINCOP IES OP f"EDERALSPECIPICA 

TIONS ANDSTANDARDSANI)THE INDEXOP f"EDEFlALSPECIF'ICATIONS ANDSTANDARDSPFlOM 

ESTABLISHEDDISTRI8UTION POINTS IN THEIR AGENCIES.) 

MILITARY STANDARD: 

MIL-STD-105 - SAMPLINGPROCEDURESANDTABLES F'OR INSPECTIONBY 

ATTRIBUTES. 

(COPIES OP MILITARY STANDARDREPERENCEDABOVE, REQUIREDBY CONTRACTORS 

IN CONNECTIONWITH SPECIPIC PROCUREMENTPUNCTIONS, SHOULDBE OBTAINEDPROM 

THE PROCURrNGAGENCYOR AS DIRECTEDBY THE CONTRAC,!'NGOPPICER.) 

2.2 OTHERPUBLICATIONS- THE POLLOWINGPUBLiCATIONS, OF' THE ISSUE IN 

EPF'ECTON DATEOP INVITATION F'ORBIOS, POFlMSA PART OF' THIS SPECIF'ICATION: 

GOVERNMENTAL: 

f"EDERALINSECTICIDE, f"UNGICIDE, ANDRODENTICIDEACT. 

(COPIES OP THE f"EDERALINSECTICIDE, f"UNGICIDE, ANDRODENTICIDEACT MAY 

BE OBTAINEDF'ROMTH£ SUPERINTENDENTOP DOCUMENTS,GOVERNMENTPRINTING OPPICE, 

WASHINGTON25, D. C. PRICES MAY,BE OBTAINEDF'ROMTHE SUPERINTENDENTOP 

DOCUMENTS.) 

3. REQUIREMENTS

3.4 WOAKMANSHIP,-THE FINISHED PRODUCTSSHALL BE CLEANANDUN'~ORM, AND 

. mEE FROMANYDEFECTSWHICHMIGHT IMPAIR THEIR UTILITY. 

453 

80 PERCENT2,4-DICHLOROPHENOXYACETICACID AS DETERMINEDIN 4.4.1. THE PRODUCT 

SHALLBE SOLUBLEIN SOFT OR HARDWATER(600 PPM. CALCIUMCARBONATE)AT THE 

CONCENTRATIONSPECIFIED IN THE DIRECTIONS FOR USE, NON-FOAMING,ANDCONTAIN 

NO INGREDIENTSWHICHWILL INHIBIT THE APPLICATIONOF THE MATERIALAT THE CON 

CENTRATIONSNORMALLYUSED FOR WEEDCONTROL. 

3.2 TYPE 11.- THE LIQUID AMINESALT FORMOF 2,4-DICHLOROPHENOXYACETIC 

ACID SHALLCONTAINA MINIMUMOF FOURPOUNDSOF 2,4-0 ACID PER GALLONOF FOR 

MULATIONAT saOF., AS DETERMINEDIN 4.4.2 THE A~IINE IN THE FORMULATIONSHALL 

BE EITHER THE ALKYLOR ALKANOLAMINEOR MIXTURESOF THESE TYPES. THE PRODUCT 

SHALLBE SOLUBLEIN HARDOR SOFT WATERAT THE CONCENTRATIONSPECIFIED IN THE 

DIRECTIONS FOR USE, NON-FOAMING,DISPERSE EASILY, MAKINGA SOLUTIONTHATCON 

TAINS NO INGREDIENTSWHICHWILL INHIBIT THE APPLICATIONOF THE MATERIALAT THE 

CONCENTRATIONSNORMALLYUSED FOR WEEDCONTROL. THE PRODUCTSHALLCONTAINNO 

INGREDIENTSWHICHWILL COAGULATEWITH WATER. THE MATERIALSHALLCONTAIN 

SEQUESTER'iNGAGENTSWHICHFACILITATE ITS APPLICATION IN HARDOR SOFT WATER. ; ',', 

3.3 TYPE 111.- THE LIQUID ESTER FORMSOF 2,4-DICHLOROPHENOXYACETICACID. 

3.3.1 CLASS 1.- THE VOLATILEESTERS OF 2,4-DICHLOROPHENOXYACETICACID. 

THE ALKYLLIQUID ESTERS OF 2,4-0 SHALLCONTAINA MINIMUMOF TWOPOUNDSOF 

2,4-0 ACID PER GALLONOF FORMULATIONAS DETERMINEDIN 4.4.3. THE ESTERS IN 

THIS CLASS SHALLBELONGTO THE ALKYLGROUPSUCHAS METHYL,ETHYL, PROPYL, ISO 

PROPYL, BUTYL, AMYL,ANDPENTYL, OR MIXTURESOF THESE ALKYLESTERS. THE FORM 

ULATIONSHALLBE A CLEAR SOLUTIONREADILYMISCIBLE WITH OIL ANDEMULSIFIABLE 

WHENMIXEDWITH WATER. IT SHALLCONTAINTHE NECESSARYSOLVENTS, CARRYINGAND 

EMULSIFYINGAGENTS, SUCHTHAT THE EMULSIONFORM~O REQUIRES A MINIMUMOF 

AGITATIONTO MAINTAiN INTIMATEMIXTUREWITH THE DILUENTDURINGTHE MIXING AND 

APPLICATIONPERIOC. THE OIL CARRIER FOR THE FORMULATIONSHALLBE OF SUCH 

GRAVITYANDVISCOSITY, NOT DETRACTINGFROMTHE KILLING POWEROF THE ACTIVE IN 

GREDIENTS, TO OFFER MAXIMUMPENETRATIONAND SPREADOF THE SPRAYSOLUTION. 

3.3.2 CLASS 2,- THE LOWVOLATILEESTERS. THESE INCLUDETHE GLYCOL,POLY 

GLYCOLANDTHEIR ETHERESTER DERIVATIVESOF 2,4-0, AS WELLAS OTHERHEAVY 

_,MOLECULARWEIGHTESTERS OF 2,4-0 THAT ARE KNOWNTO BE LOWVOLATILE. THE LOW 

VOLATILEESTERS OF 2,4-0 SHALLCONTAINA MINIMUMOF FOURPOUNDSOF 2,4-0 ACID 

PER GALLONOF FORMULATIONAT 68 0 F., AS DETERMINEDIN 4.2.3. THIS CLASS SHALL 

NOT INCLUDEESTERS OF THE LOWERALKYLGROUPSUCHAS METHYL,ETHYL, PROPYL, 

ISOPROPYL, BUTYL, AMYL,ANDPENTYL, OR MIXTURESOF THESE ALKYLESTERS. THE 

FORMULATIONSHALLBE READILY MISCIBLE WITH OIL ANDEMULSIFIABLEWITHWATER. 

THE PRODUCT~HALL BE A cLEAR SOLUTION, ANDSHALL INCLUOETHE NECESSARYSOLVENTS, 

CARRYINGANDEMULSIFYINGAGENTS, SUCHTHATTHE EMULSIONFORMEDREQUIRES A MINI 

MUMOF AGITATION.TOMAINTAIN INTIMATEMIXTUREWITH THE DILUENT DURINGTHE 

MIXING ANDAPPLICATIONPERIOD. THE OIL CARRIER FOR THE FORMULATIONSHALLBE 

OF SUCHGRAVITYANDVISCOSITY, NOT DETRACTINGFROMTHE KILLING POWEROF THE 

ACTIVE INGREDIENTS, TO OFFER MAXIMUMPENETRATIONANDSPREADOF THE SPRAYSOLU 

TION. WHENTESTED FOR VOLATILITYAS DESCRIBED IN 4.4.4. THE PRODUCTSHALL 

HAVEAN AVERAGERESPONSEOF LESS THAN4.0.

454 

4. SAMPLING, INSPECTION, ANDTEST PROCECUREb 

4.1 SAMPLINGFOR LOT ACCEPTANCE. 

4.1.1 INSPECTIQNLOT.-'FOR PURPOSESOF SAMPLING, A LOT,SHALL CO~~i.s.T, OF 

ALL ~ATtRIAL otF~REO FOR INSPECTION AT ONE TIME. IN CASE MATERIALIS PRODUCED 

BY A CONTINUOUS-RUN PROCESS THE LOT SHALLCONTAIN MATERIAL FROMONLY ONE.'CON 

TINUOUSRUN. MATERIALIN tHE INSPECTION LOT SHALLBE IDENTIFIED BY ORDEROF 

PRODUCTION(IN CASE OF A CONTINUOUS-RUNPROCESS~ OR BY BATCHNUMBER(IN CASE 

OF 'BATCHPROCESS) UNTIL ULTIMATEACTION IS TAKENBY THE GOVERNM~NT INSPECTOR 

AS TO THE ACCEPTANCEOR REJECtiON OF THE LOT. 

4.1.2 SAMPLING~OR INSPECTION OF FILLED CONTAINERS.- A RANDOMSAMPLEOF 

FiLLED CONTAII~ERS SHALLBE TAKENFROMEACHLOT By THE GOVERNMENTINSPECTOR, 'IN 

ACCORDANCEWITHMIL-STD-105 AT INSPECTION LEVEL I, ANDACCEPTABLEQUALITY, 

LEVEL (A.Q.L.) = 2.5 PERCe:N1'DEFECTIVE TO VERI/".YCOMPLIANCEW!TH ALL ST1PU,,"A 

TIONS OF THIS SPECIFICATION REGARDINGFILL, CLOSURE, MARKING,ANDOTHERREQUiRE 

MENTSNOT INVOLVINGTESTS. 

4.1.3 SAMPLINGFOR TESTS.- FROMEACH INSPECTION LOT THE GOVERNMENTINSPEC 

TOR SHALLTAKETHREE SEPIIRATE1-POUND OR 1-GALLONSAMPLES, IN CASE THE 

MATERIALIS PRODUCEDBY A BATCHPROCESS, ANCTHE INSPECTIONLOT CONTAINSMORE 

THAN2 BATCHES, THE THREE SAMPLESSHALL NCP-MALL Y Bt TAKENFROM0 I FF'e:'REN~ 

BATCHES, FROMTIME TO TIME; HOWEVER,AT THE DISCREtiON OF THE INSPECTOR, T,WO 

OR ,THREEOF THE S,t.i'1"LESSHALLBE TAKENFROMTHE SAMEBATCH, IN WHICH CASE THE 

SAMPLESSHALLBE OtlTAINED IN A MANNERCALCULATEDTO DISCLOSE ANYNON-UNIFCRM~ 

fTY OF THE MATERIALWITHIN THE BATCH. WHERE~1ATER!AI. IS PRODUCEDDY A CON 

TINUOUS-RUNPROCESS THE THREE SAMPLESSHALLBE TAKENSO AS TO REPRESENT 

RESPECTIVELY, THE FIRST PART, THE MIDDLEPART, ANDTHE LAST PART OF THE RUN 

WHICHPRODUCEDTHE INSPECTION LOT, EACH SAMPl.ESHALl. BE THOROUGHLYMIXEDAND 

DIVIDED INTO THREE EQUALPORTIONS. THE PORTIONS SHALL BE Pl.ACED IN SEPARATE, 

Cl.EAN, DRY, Mf'rAL OR Gl.ASS CONTAINERS,WHICHSHALLBE SEALEDANDCAREFULl.Y 

MARKED. ONE Or- THE PORTIONS OF EACH SAMPl.ESHAl.L BE FORWARDEDTO A GOVERNMENT 

LABORATORYDESIGNATEDBY THE BUREAUOR AGENCYCONCERNED,ONE SHALLBE DELIVERED 

TO THE CONTRACTOR,ANDONE HELD BY THE GOVERNMENTINSPECTORTO BE USED FOR 

RETESTS IN CASE OF DISPUTE. 

4 02 INSPECTION 

4.2.1 INSPECTION OF FILLED CONTAINERS.- EACH SAMPLEFILLED CONTAINER 

SEl.ECTED IN ACCORDANCEWITH 4.1.2 SHALL BE EXAMINEDBY THE GOV~RNMENT INSPECTOR 

FOR DEFECTSOF THE CONTAINERANDTHE CLOSURE, FOR EVIDENCEOF LEAKAGE,ANDFOR 

UNSATISFACTORYMARKINGS. EACHSAMPLEFILLED CONTAINERSHALLALSO BE WEIGHED 

TO DETERMINETHE A~OUNT OF THE CONTENTS. ANYCONTAINERIN THE SAMPLEHAVING 

ONEOR MOREDEFECTS, OR UNDERREQUIREDFILL, SHALLBE REJECTED, AND IF THE 

NUMBEROF DEFECTIVECONTAINERSIN ANY SAMPLEEXCEEDSTHE ACCEPTANCENUMBERFOR 

THE APPROPRIATESilj·\PLING PLIIN OF MIL-STO-105 THE LOT REPRESENTEDBY THE SAMPLE 

SHALLBE REJECTED. REJECTED LOTS MAYBE RESUBMITTEDFOR ACCEPTANCETESTS PRO 

VIDED THATTHE CONTRACTORHAS REMOVEDOR REPAIRED ALl. NONCONFORMING CCNTAINERS. 

4.3 LOT ACCEPTANCETESTS,- THE SAMPLESPECIMENSSELECTEDIN ACCORDANCE 

WITH 4.1.3 SHALLBE SUBJECTEDSEPARATELYTO THE TESTS SPECIFIED IN 4,4 IF ~ 

EITHER S~ECjMEN FA;!.S IN ONE Of! MOREOF THE TESTS THE LOT SHALLBE REJECTED. 

REJECTED LOTS MAYBE RESUBM,ITTEDFOR ACCEPTANr..T.~T _","n.-n TUe-"".,-roA,,""'"

455 

4,4 TEST PROCEDURES 

4,4.1 2,4-DICHLOROPHENOXYACETICACID C~NTENT IN SODI~M SALT O~ 2,4 

DICHLOROPHENOXYACETIC ACID MONOHYDRATE.DISSOLVE A SAMPLEEQUIVALENTTO ABOUT 

1 G. OF 2,4-0 ACID OR 1.20 - 1,25 G O~ THE SeDIUM SALT IN 50 ML. O~ WATER, 

TRANS~ER TO 250 ML, SEPARATORYFUNNEL. NEUTRALIZE I~ NECESSARYWITH 1~ H2S04, 

ANDADD10 ML. IN EXCESS. EXTR~eT THE AQUEOUSPHASE TWICE WITH 75 ML. PORTIONS 

OF ETHER. WASHTHE COMBI NED ETHER EXTRACTSF'REE ~ROM MINERALACI 0 WITH 3 POR- 

". TIONS O~ WATEREXACTLY10 ML. EACH, AVOID SLIGHT EMULSI~ICATION BY EXCESSIVE 

SHAKING. rlLTER THE ETHER SOLUTIONTHROUGHA ~UNNEL CONTAININGA SMALLPIECE 

O~ COTTONPREVIOUSLYSATURATEDWITH ETHER INTO A 400 ML. BEAKER, RINSING THE 

SEPARATORYFUNNELWITH ETHER. ADD25 ML. OF WATER, A FEWBOILING CHIPS, AND 

EVAPORATEOFF THE ETHERLAYERON A STEAMBATHUNTIL APPROXIMATELY25 ML. OF' 

ETHERREMAINS. REMOVETHE BEAKERFROMTHE STEAMBATHANDEVAPORATEOFF' THE 

REMAININGPORTIONOF ETHER AT ROOMTEMPERATUREBY MEANSOF A CURRENTOF' AIR. 

DISSOLVE THE AQUEOUSMIXTURE IN 100 ML. OF NEUTRALETHYLALCOHOLANDTITRATE 

WITH 0,1 N NAOHUSING 1 ML. OF' IND/CATeRS. (LG IN 100 ML. OF' ALCOHOL) • 

• EITHER PHENOLPHTHALEINOR THYM~LPHTHALEIN MAYBE USED IN THE TITRAT/ON 

PROVIDEDTHE ~NE SELECTED IS USED IN STANDARDIZATIONO~ THE SODIUMHYDROXIDE. 

EACHML. OF' 0.1 N NAOHIS EQUIVALENTTO 0.02210 G OF' 2,4-DICHLOROPHENOXY 

ACETIC ACID OR 0.02610 G OF' SODIUMDICHLOROPHENOXYACETATE. REF'ERENCE. METHODS 

OF ANALYSIS, ASSOCIATIONor OFF'ICIAL AGRICULTURALCHEMISTS, 8TH ED., PAR. 5.133 

(C), PAGE 75. 

4.4.2 ~-DICHLOROPHENOXYACETIC ACID CONTENTIN AMIN SALTS OF' 2 4-DICHLCR 

ClPHENOXYACETICACID" TpANsrER A SAMPLEEQUIVALENT OR A SUITABLE ALIQUI"TOF A 

'SAMPLEDILUTEDWITH WATER)TO ABOUT1 G OF 2,4-0 ACID TO A 250 ML SEPARATORY 

F'UNNEL. DILUTE TO 50 ML. OF WATERANDPROCEEDAS DIRECTED IN 4.4,1. CALCULATE 

THE PERCENT2,4-0 ACID FOUNQTO THE SPECIFIC AMINEPRESENT IN THE SAMPLE. 

4.4.3 

CHL~INE. WEIGHANDMIX 1,5 G OF BORIC ANHYDRIDE 

',#2685 OR EQUIVALENT), 1 00 G F'INELY POWDEREDPOTASSIUMNITRATE, AND0.4 G F'INELY 

'\ pnWDEREDSUCROSE. TRANsFERAPPROXIMATELY"NE-FOURTH'OF'THIS MIXTURETO A 42 ML. 

PARR BOMBELECTRIC IGNITION TYPE, ANDADDFROMA SMALLWEIGHINGBURETABOUT 

0.25 - 0.30 G OF SAMPLECONTAININGFROM0.030 - 0.034 G CHLORINE, (WHENA SAMPLE 

LARGERTHAN0.30 G IS REQUIRED, 2.5 G OF BORIC ANHYDRIDESHOULDB..E 'USED, IN NO 

. CASES SHOULDA SAMPL~ L~RGER THAN0.6 G BE TAKEN.) MIX WELLWITH A THIN STIRRING 

. ,ROO. ADDTHE REMAINDEROF' THE BORIC ANHYDRIDE,POTASSIUMNITRATE ANDSUCROSE 

MIXTUREIN SMALLPORTIONS ANDTHOROUGHLYMIX AFTER EACHADDITION. MEASURE15 G 

OF CALORIMETRICGRADESODIUMPEROXIDE I~A STANDARDMEASURINGDIPPER, ADOA 

,SMALLPORTIONTO THE CONTENTSOF' THE BOMB, ANDSTIR. ADOTHE BALANCEOF S'ODIUM 

PEROXIDEANDTHOROUGHLYMIX BY STIRRING WITH THE ROD. WITHDRAWTHE ROOAND 

BRUSHFREE OF ADHERINGPARTICLES, QUICKLYCUT OR BREAKOFF THE LOWER1t INCHES 

Or THE STIRRING ROD AND IMBED IT IN THE FUSION MIXTURE. SPRINKLE ON THE TOP OF 

THE ~USION MIXTUREA SMALLQUANTITYOF rtNELY GROUNDSUCROSE. PREPARETHE HEAD 

BY HEATINGTHE FUSE WIRE MOMENTARILYIN A FLAMEAND IMMERSINGIT INTO A SMALL 

QUANTITYOF SUCROSE. ONE MILLIGRAMOF THE SUBSTANCEIS SU~FICIENT TO STARTTHE 

COMQUSTION. ASSEMBLETHE BOMBAND IGNITE IN THE USUALMANNERWITH A SATISFAC 

TORYSHIELD BETWEENTHE OPERATORANDAPPARATUS.

456 

PLACE ABOUT100 ML. OF DISTILLED WATERIN 600 ML. BEAKERANDHEATNEARLY 

TO BOILING. AFTER COOLINGOF THE BOMB, DISMANTLEIT ANDDIP THE COVER IN THE 

HOT WATERTO DISSOLVE ANYOF THE FUSION WHICHMAYBE ADHERINGTO ITS UNDERSIDE. 

WASHCOVERWITH A FINE JET OF DISTILLED WATERCATCHINGTHE WASHINGSIN THE 

BEAKER. WITH A PAIR OF TONGSLAY THE FUSION CUP ON ITS SIDE IN THE SAMEBEAKER 

OF HOT WATER,COVERINGIT IMMEDIATELYWITH A WATCHGLASS. AFTER THE FUSED 

MATERIALHAS BEEN DISSOLVED, REMOVETHE CUP ANDRINSE WITH HOT WATER,COOLTHE 

SOLUTION, ADOSEVERALDROPSOF PHENOLPHTHALEININDICATOR, N£UTRALI'ZEWITHCON 

CENTRATEDNITRIC ACID ANDADO5 ML. IN EXCESS. FROMTHIS POINT, THE'CHLORINE 

MAYBE DETERMINEDBY ELECTROMETRICTITRATION OR BY THE VOLHARDPROCEDUREAS 

DIRECTED IN THE METHODSOf ANALYSIS, ASSOCIATIONOF OFFICIAL AGRICULTURAL 

CHEMISTS, 8TH Eo., PAGE BO, PAR. 5.153 (A) (C). 

NOTE 1.- THE COMBINATIONOF MATERIALSUSED IN A SODIUMPEROXIDEBOMBHAS 

EXPLOSIVE PROPERTIES II'" WRONGLYHANDLED,ANDTHE OPERATORSHOUI.DREM'AIN"FULLY 

AWAREAT ALL TIMES OF THE PRECAUTIONSTHATMUSTBE OBSERVEDANDTHE'STbs WHICH 

MUSTBE TAKENTO AVOID DAMAGETO THE APPARATUSANDPOSSl3LY PERSONALINJURY, 

IT IS SUGGESTEDTHAT THE INSTRUCTIONSANDPRECAUTIONSGIVEN IN THE "PARR MANUAL 

NUMBER121 - PERIOXIDE BOMBAFPARATUSANDMETHODS,· PARR INSTRUMENTCOMPANY, 

MOLINE, ILLINOIS, BE OBSERVED. 

/'lOTE2.- A FLAMEFIRED BOMBMAYBE USED IN PLACE OF THE ELECTRIC IGNITION 

TYPE",BUT IN CASE OF DISPUTE THE ELECTRIC IGNITION TYPE WILL GOVERN. 

4.4.4., VQLATILITY HST - RELATIVE VAPORACTIVITY.- THE VAPORACTIVITY TEST 

IS CONDUCTEDWITH GASTIGHTCELLOPHANECASES AP~ROXIMATELY 3., X 3!- X 16 INCHES 

IN SIZE. YOUNGRAPIDLY GROWINGPINTO BEANPLANTS ABOUT4 INCHES IN HEIGHT ARE 

USED AS TEST PLANTS. A SINGLE BEANPLANT GROWINGIN A 3 INCH POT IS PLACED IN 

EACHCELLOPHANECASE JUST PRIOR TO TESTING THE ESTER. 

4.4.4.1.- Two MILLIGRAMSOF ACID EQUIVALENTAS THE ESTER IS DISSOLVED IN 

10 MILLILITERS OF 95% ETHYLALCOHOLANDA WHATMANo.1 FILTER PAPER (9 CM. 

DIAMETER) IS THOROUGHLYMOISTENEDBY DIPPING IN THE SOLUTION. (DO NOT REUSE 

THE CONTAINERUSED IN THIS IMPREGNATION,) THE ALCOHOLIS THEN ALLOWEDTO 

EVAPORATEANDTHE FILTER PAPER IMPREGNATEDWITH THE ESTER IS INSERTED INTO THE 

CELLOPHANECASE CONTAININGTHE BEANPLANT ANDFASTENEDTO THE INSIDE OF THE CASE 

6 INCHES ABOVETHE LEAVESOF THE TEST PLANT. THE OPEN END OF THE CASE IS THEN 

SEALED. 

4.4.4.2.- THF.CASE CONTAININGTHE TEST PLANT ANDTREATEDFILTER PAPER IS 

THEN PLACED IN A DARKROOMFOR A PERIOD OF 24 HOURS, THE TEMPERATURERANGEOF 

THE ROOMSHOULDBE 80 0 TO 900F, CONTROLPLANTS ARE ALSO SEALED IN SEPARATE 

CASES, THE EXPERIMENTALDESIGN IS A RANDOMIZEDBLOCKWITH THREEREPLICATIONS 

ANDEACHTEST IS REPEATEDTHREE TIMES. THE EVALUATIONSSHALLBE MADEFOLLOWING 

AN EXPOSUREPERIOD OF 24 HOURS. 

4.4.4.3,- OBSERVATIONSOF EFFECT OF THE VAPORSON TEST PLANTS SHOULDTAKE 

INTO CONSIDERATIONWHETHEROR NOT THE PLANT IS S~IGHTLY, MODERATELYOR SEVERLY 

INJURED, INCLUDINGSUCH SYMPTOMSAS DEGREEOF STEMCURVATURE,TERMINALBUD IN 

HIBITION ANDDEGREEOF LEAF CURL. THE RELATIVE VAPORACTIVITY OF AN ESTER CAN 

BE NUMERICALLYDESIGNATEDAS FOLLOWS: a - NO VISIBLE EFFECT; 1 I 2, 3 - SLIGHT 

INJURY - PLANTUSUALLYRECOvEREDWITH LITTLE OR NO REDUCTIONIN GROWTH,SLIGHT 

EPINASTY PRES~NT_ STF'M ~IlRVATIlRF' SL 1f.lIolT, 4. !'i. fi _ Mnn"RAT .. IN,IlIR" _ PI At.lT

457 

MODERATESTEMCURVATUREPRESENT; 7, 8, 9 - SEVERE INJURY ~ P~ANT USUALLYDOES 

NOT RECOVER, PRONOI,;NCEDEP I NASTY. TOGETHERWITii PR0NOUNCEDSTEMCURVATURE; 

10 - PLANT KILLED. 

4.4.4.4- CHEMICALLYPURE 2,4-0 ACID AND THE BUTYLESTER O. 2,4-0 ARE 

USED AS STANDARDS. THE 2,4-0 ACID UNDERMMT CONDITIONS IS RATED0 (ZERO) 

WHILE THE BUTYLESTER HAS A HIGH VAPORACTIVITY WITH A RATING 0.9.0 ESTERS 

RECEIVING THE.• OLLOWINGRA;r'NGS WOULDBE CLASSEDAS.• QLLOWSI 

o 

1,2,3 

4,5,6 

7,8,9 

10 

NO VAPORACTIVITY 

VERYLOWVAPORACTIVITY 

LOWTO MODERATEVAPORACTIVITY 

HIGH VAPORACTIVITY 

VERYHIGH VAPORACTIVITY 

ESTERS MUSTRECEIVE A VAPORACT.IVITY RATING OF"LESS THAN4 TO BE OESIGNATEDLOW 

VOLATILE. 

5. PREPARATiONFOR DELIVERY (FOR DE. INIT IONS ANDLEVELS SEE 6.1) 

5.1 PRESERVATIONANDPACKAGINGLEVELS. 

5.1.1 LEVEL A.- TO BE INSERTEDBY THE DEPARTMENTOF DE'ENSE. 

5.1.2 LEVEL B 

5.1.2.1 ~ - TYPE I SHALL BE PACKAGEDIN 50-POUND .IBER DRUMS. DRUMS 

SHALLCON.ORMTO fEDERAL SPtCI.ICATION PPP-D-723. 

5.1.2.2 TYPES " ANDTYPES II I 

5.1.2.2.1 UNIT CONTAINERS.- THE MATERIALSHALLBE PACKAGEDIN 1-GALLON 

METALCANS, ~IHICH SHALL BE OBLONG,CON.ORMINGTO TYPE V O. fEDERAL SPECI.,CATION 

PPP-C-96. CANS MAYHAVEEITHER A CLASS 4 SCREWCAP OR CLASS 5 SNAP-ON CAP. 

THE CONTAIN.ERSSHALLCAUSENO DELETERIOUSE.n:CT UPONTHE PRODUCT. 

5.1.2.2.2 BULKCONTAINERS.- THE MATERIALSHALL BE PACKAGEDIN 5-GALLON 

OR 55-GALLON CONTAINERS, AS SPECI. lED IN THE CONTRACTOR ORDER. fiVE GALLON 

METALCONTAINERSSHALL CON.ORMTO TYPE I, CLASS 1 OR 2, O. fEDERAL SPECI.ICA 

TION PPP-D-760. fl.TY-.IVE GALLONDRUMS~HALL CON.ORMTO EITHER TYPE I I OR 

TYPE IV O. fEDERAL SPECI.ICATION PPP-D-729. THE CONTAINERSSHALLCAUSENO 

DELETERIOUSEF.ECT ON THE PRODUCT. 

5.1.3 LEVEL C.- THE PRODUCTSHALL BE PACKAGEDIN ACCORDANCE·WITHCOMMER 

CIAL PRACTICE. 

5.2 PACKING. 

5.2.1 LEVEL A.- To BE INSERTEDBY THE DEPARTMENTO. DE.ENSE, I. REQUIRED. 

5.2.2 LEVEL B.- 

5.2.2.1 ~.- fl.TY-PCUND .IBER DRUMSWILL REQUIRE NO OVERPACKING.

458 

5.2.2.2 TYPES II AND III 

5.2.2.2.1 UNIT CONTAINERS.- ONE-GALLONCANS SHALLBE PACKEDFOR SHIPMENT 

IN ACCORDANCEWITH THE APPENDIXOF FEDERALSPECIFICATION PPP-C-96. 

5.2.2.2.2 BULKCONTAINERS.- FIVE-GALLONANOFIFTY-FIVE GALLONQRUMSWILL 

REQUIRE NO OVERPACKING. 

5.2.3 LEVEL C.- THE PRODUCTSHALL BE PACKEDIN CONTAINERSWHICHARE 

ACCEPTABLEBY COMMONOR OTHERCARRIERS FOR SAFE TRANSPORTATIONTO POINT OF 

DESTINATIONSPECIFIED IN SHIPPING INSTRUCTIONSAT THE LOWESTTRANSPORTATIONRATE 

FOR SUCH SUPPLIES. 

5.2.4 LEVEL 0.- To BE INSERTED BY THE DEPARTMENTOF DEFENSE IF REQUIRED. 

5.3 MARKING. 

5.3.1 CIVILIAN AGENCIES,.- IN ADDITION TO ANYSPECIAL MARKINGREQUIREDBY 

THE CONTRACTOR ORDER, MARKINGFOR SHIPMENTSHALL BE IN ACCORDANCO:: WITH FEDERAL 

SPECIFICATION PPP-P-31. 

5.3.1.1 LABELING.- UNLESS OTHERWISESPECIFIED, EACHCONTAINEROF 2,4-0 

FORMULATIONSHALL BE LABELEDWITH INSTRUCTIONSFOR USE ANDMARKEDIN COMPLIANCE 

WITH THE FEDERAL INSECTICIDE, FUNGICIDE, ANDRODENTICIDEACT ANDOTHERAPPLI 

CABLE EXISTING FEDERALLAWS. DATE OF PACK ANDLOT NUMBERSHALL APPEARON THE 

LABEL. IN ADOIT ION, THE COVERSHALLHAVETHE STOCKNUMBERAND ITEMNOMEN 

CLATURESHALLBE EMBOSSEDON A METALPLATE ANDWIRED SECURELYTO THE INDIVIDUAL 

CONTAINER. 

6. NOTES 

6.1 FEDERALSTANDARD102 SHOULDBE REF"ERREDTO FOR DEFINITIONS ANDAPPLI 

CATIONS OF THE VAR;OUSLEVEL OF PACKAGINGPROTECTIONF"ORSUPPLIES ANDEQUIPMENT, 

6.2 INTENDEDUSE. 

6.2.1 lrf1-l.- THE MONOHYDRATE SODIUMSALT DRY POWDERFORMOF 2,4-0 IS 

SPARINGLY WATERSOLUBLE. ITIS ESPECIALLY ADAPTEDFOR LAWNS"CEMETERIES AND 

IN OTHERAREASWHEREDESIRABLE VEGETATIONSUCH AS F"LOWERSANDORNAMENTALSARE 

LIKELY TO BE INJURED BY SPRiIV DRIFT OR VAPORS. THE,pRY POWDERSODIUMSALT FORM 

IN WATERSOLUTION IS USEFU~ ON EASY-TO-KILL WEEDS. THE MAIN DISADVANTAGEOF 

THE POWDERFORMOF 2 14-0 IS ,HAT IT IS NOT AS EFFECTIVE AS EITHER THE AMINESALTS 

OR ESTERS OF 2,4-0 ON HARD-,O-KILL WEEDSOR OLDERWEEDS. SOMENOZZLECLOGGING 

ANDOTHERAPPLICATION DIFFICULTIES ARE LIKELY TO RESL:LTDUE TO INCOMPLETESOLU 

TION OF THE SODIUMSALT WHENTHE DRY POWDERFORM IS APPLIED AT HIGH RATES WITH 

LOWGALLONAGESPRAYERS. THE EFFECTIVENESS OF THE SODIUMSALT OF"2,4-0 IS RE 

DUCEDWHENRAINS OCCURIMMEDIATELYFOLLOWINGAPPLICATION. THE SODIUMSALT OF 

2,4-0 IS THE LEAST TOXIC FORMPER POUNDOF 2,4-0 ACID TO PLANTS AS SPECIFIED 

IN TYPES I, II, OR I II. 

6.2.2 TYPE 11.- THE LIQUID AMINEFORMSOF 2,4-0 ARE HIGHLY SOLUBLEIN 

WATER,MAKINGA RELATL'ELY CLEAR SOLUTION. THEY ARE QUITE STABLEANDARE 

EFFECTIVE F"OREASY-TO-KILL OR MODERfTELYEASY-TO-KILL WEEDS. THE AMINESALTS 

OF 2,4-0 ARE MUCHLESS VOLATILETHANTHE ESTER FORMSOF,2,4-0 ANDARE SOMEWHAT

459 

B[TTER ADAPTED rOR SPRAYING rOR WEED CONTROL NEAR PLANTS SENSITIVE TO 2,4-0. 

THE LIQUID AMINE SALT rORMS OF 2,4-0 ARE WELL ADAPTED rOR SPRAYING IN LA~NS, 

TURrED AREAS, AND IN TOLERANT FIELD AND HORTICULTURAL CROPS rOR WEED CONTROL. 

THE AMINE SALTS OF 2,4-0 ARE NOT QUITE AS EFFECTIVE ON OLD, SEMI-RESISTANT WEEDS 

AND WOODYSPECIES AS ARE THE ESTERS. THE AMINE SALTS OF 2,4-0 ARE MORE TOXIC TO 

PLANTS THAN THE SODIUM SALT or 2,4-0, BUT LESS TOXIC TO PLANTS THAN THE ESTERS or 

2,4-0 PER POUND or 2,4-0 ACID. 

6.2.3 TYPE I 11.- THE LIQUID ESTER FORMS or 2,4-DICHLOROPHENOXYACETIC ACID. 

6.2.4 CbASS 1.- THE LOWER ALKYL ESTERS or 2,4-oICHLOROPHENOXYACETIC ACID 

ARE COMPARATIVELY VOLATILE. WHEN THE LOWER ALKYL ESTERS OF 2,4-0 ARE USED rOR 

WEED CONTROL IN TOLERANT rlELD AND HORTICULTURAL CROPS THEY SHOULD BE USED AT 

LOWER ACID EQUIVALENT RATES THAN EITHER THE SODIUM OR AMINE SALTS or 2,4-0. THE 

LOWER ALKYL ESTERS or 2,4-0 ARE BETTER ADAPTED FOR THE CONTROL or DEEP ROOTED 

PERENNIAL WEEDS, HARDER-TO-KILL WEEDS, OLDER SEMI-RESISTANT WEEDS AND WOODY 

SPECIES THAN THE SODIUM OR AMINE SALTS OF 2,4-0. THE LOWER ALKYL ESTERS OF 2,4-0 

SHOULD NOT BE USED IN AREAS NEAR SENSITIVE CROPS SUCH AS COTTON, GRAPES, TOMATOES, 

TOBACCO, AND OTHER SENSITIVE CROPS. 

6.2.5 CLASS 2.- THE LOW VOLATILE ESTERS or 2,4-0 HAVE THE SAME INTENDED 

USE AS THE ESTER rORMS SPEClrlED IN CLASS 1. HOWEVER, IN AREAS WHERE SENSITIVE 

CROPS ARE GROWNSUCH AS COTTON, ETC., Ir AN ESTER rORM OF 2,4-0 IS NECESSARY, 

THE ESTERS SPEClriED IN CLASS 2 SHOULD BE USED TO REDUCE THE HAZARD or VOLATILITY. 

6.3 ORDERING DATA - PURCHASERS SHOULD EXERCISE ANY DESIRED OPTIONS orrERED 

HEREIN (SEE 1.2, 5.1, 5.2, 5.3) (ALSO SEE 6.4 rOR BASIS or AWARD). 

6.4 BASIS or AWARD 

6.4.1 l!ff-l.- BIDS SHOULD BE EVALUATEO AND THE AWARDMADE ON THE BASIS 

or COMPUTING THE PRICE PER pOUNDeF 2,4-0 ACID EQUIVALENT CONTAINED PER POUND or 

BULK. (SUPPLIER SHOULD BE REQUESTED TO rURNISH 2,4-0 ACID EQUIVALENT DATA). 

6.4.2 TYPE II AND III (CLASSES 1 AND 2).- BIDS SHOULD BE EVALUATED AND THE 

AWARDMADE ON THE BASIS or COMPUTING THE PRICE PER POUND OF 2,4-0 ACID EQUIVA 

LENT CONTAINED IN EACH GALLON or PREPARATION OR CONCENTRATE (SUPPLIER SHOULD BE 

REQUESTED TO rURNISH 2,4-0 ACID EQUIVALENT DATA). 

PATENT NOTICE.- WHEN GOVERNMENTDRAWINGS, SPEClrICATIONS, OR OTHER DATA 

ARE USED rOR ANY PURPOSE OTHER THAN IN CONNECTION WITH A DErlNITELV RELATED 

GOVERNMENTPROCUREMENTOPERATION, THE UNITED STATES GOVERNMENTTHEREBV INCURS 

NO RESPONSIBILITV NOR ANY OBLIGATION WHATSOEVER; AND THE FACT THAT THE GOVERN 

MENT MAY HAVE FORMULATED, rURNISHED, OR IN ANY WAY SUPPLIED THE SAID DRAWINGS, 

SPEClrlCATIONS, OR OTHER DATA, IS NOT TO BE REGARDED BY IMPLICATION OR OTHERWIS£ 

AS IN ANVMANNER LICENSING THE HOLDER OR ANY OTHER PERSON OR CORPORATION, OR 

CONVEYING ANY RIGHTS OR PERMISSION TO MANurACTURE, USE, OR SELL ANY PATENTED 

INVENTION THAT MAY IN WAY BE RELATED THERETO.

460 

PROGRESSREPORr ONHIGHWAYGUARDRAILVLGETATIONCONTROL 

R. ri. Johnson l• J.E. Gallagher l• E.W. Muller 2 

Introduction: 

Chemical treatment of highway guardrail areas to control weed growth and 

reduce mowing coat.s has become an accepted practice in 1llarJ¥areas. NUlIlerous 

materials of various types have been employed with varying delreea ot success. 

The purpose ot this project was to compare several ot the standard guardrail 

treatll1ents and to determine whether new chelll1cals or chemical combinations 

would be more ettective than treatments nOlI in cOllllllOnUIIe. 

In this test twenty-tour different treatments were applied to guardrail 

vegetation in southwestern New York state in early May. Similar treatments 

were applied in central Ohio and central Connecticut in late July.3 

Methods and Materials 

Herbicide applications were made at 30 gallons .per acre with a Dragon backpack 

sprayer supplying two teejet 8002 nozBlee which stradled the guardrail and 

support posts. An area three feet wide _s treated in New York and Connecticut, 

and an 18 inch strip was treated. in Ohio. Plots were 330 teet long and were 

replicated three times. 

The New·York test was applied to guardrails along a secondary road that had 

received periodic broadleat weed control treatments for several years. 

Predominate weea species were quackgrass. orchard grass,. Kentucky bluegrass. 

and assorted biennial and perennial broadleaf weeds. including a heavy stand 

of bouncing Bet. 

In Connecticut the weed problem was similar to that in the New York test, but 

included a moderate population of brambles and blackberries. 

The Ohio test was applied to guardrails along a heavily travelea dual trunk 

highway. Vegetation consisted of a dense stand of tall fescue. red fescue 

and Kentucky bluegrass. There was a uniform light infestation of wild carrot, 

chickory and white clover. 

lResearch Department. AHCIiEMPRODUCTS.INC., Ambler. Pennsylvania. 

2Landscape Architect. New York State Department of Public Works, Hornell. 

New York. 

)I'he writers wish to acknowledge the assistance and cooperation of Mr. John 

Wright. Mr. William Greene and Mr. Edward Button, Ccmnecticut Departllent of 

Highways; Mr. Wilbur Garmhausen, Mr. James Riddle and Mr. David French. Ohio 

Department of Highways; and "Ir.H. H. lurka. State of NewYork Department of 

Public Works.

.. 461 

An inventory of the plant species present in each plot was taken before treatment 

and at each evaluation. Because of space limitations, only the vegetation 

data from the NewYork tests is included in this paper. It will be noted that 

in many treatnenta the same species appear after as well as before treatnent. 

In most such cases the stand of that weed had been reduced considerably. A 

species was listed in the "after" treatment evaluation if more than two individual 

plants occurred on the plot. 

The following materials were used in these tests: 

1. Dalapon - 2,2-dichloropropionic acid, sodium salt. 

2. 2,4-D - 2,4-dichlorophenoxyacetic acin, butoxy ethanol ester. 

3. Sili~x - 2(2,4,5-trichlorophenoxy) propionic acid. 

4. Honuron - 3(p-chlorophenyl)-1,1-dimethylurea. 

5. Simazin - 2-chloro-4,6-bis(ethylamine)-s-triazine. 

6. Amitrol - 3··amino-l,2,4-triazole. 

7. Erbon - 2(2,4,5~trichlorophenoxy) ethyl 2,2-dichloropropionate. 

8. Diethylene glycol bis 2,2-dichloropropionate. 

9. ACP-N-569 - liqt:.id amitrol. 

10. ACP-M-6l7 - 1:3 mixture of amitrol and pentachlorophenol. 

11. ACP-M-659- 1:3 mixture of amitrol and 2,2,3-trichloropropionic acid, 

sodium salt. 

12. ACP-l'-l-660- 1:3 mixture of amitrol and 2,2,J-trichloroproptonic' acid, 

sodium salt. 

13. ACP-M-673- £,3,6-trichlorophenylacetic acid, sodium salt. 

14. ACP-M-674- 2,3,6-trichlorophenylacetic acid, amide. 

In the following tables, the rate is given in pounds of active ingredient per 

acre. In Table III the following abbreviations are used: 

G c Grass control rating. 

BL = Broadleaf weed control rating. 

AV = Average control rating, G + BL 

. ~ 

Application 

dates: 

New York Test - May 8, 1958 

Connecticut Test - July 24, 1958 

Ohio Test - July. 30, 1958

) 

) 

Table I. 

I.A:rE SPiUJIG APPLICATIONOF OUlUU:i\AILVEGETATIUNCONTROL?LOTS II IIiW Y~K SUfi 

Or... ilat.1ftg ir'oelllMt lfMd ilaU. .. ........ 

31_oaAl 

'lrut..Dt. 111/1- 6/6 1/23 10/3 6/S 1/23 lith ~l 

-- -- 

. _. - . . 

---------~---~ -.- + 

--------- 

1. IMMpoD • 2.. -0 21.) .2 1.0 1.0 S.O , 7.1 6.6 6.3 I 6.6 

2. DIlbpoa • 2,4..0 • n.-r_ n.3".s 8.7 9.S 6.7 ! 1.3 8.0 1.1 I 

1.' 

... 3. Dal.ft • 2,1&-0 • ~ Y..I ..I.e '.3 8.3 S.O I -'2 "6. 7.7 

4. D1thpon. 2,b-D & 8lMa1a 21.) At AS 1.8 7.0 ,.) 1.7 1.1 '.f ,.. 

I 

S. Dalapon .. 2,lt-n .. $DaDA. l!l.2 .t ., 8.3 6.6 7.3 1.1 1.3 S., : 

I 

I '~l 

6. AQP-H-s.t.2 S.6 8.3 8.3 7.7 1.0 '.0 8.3 , a.l 

7. ACP-M-~2 11.2 9.5 9.1 9.0 I 7.3 9.1 '.0 I 

a., 

8. Aa'-n-sL2 22.4 9.8 10.0 '.1 8.1 '.0 9.0 ,~ 

9. Aa'ooH-SliJ 8.1 9.3 S.3 6.0 t.7 S.O '.J 6.6 

I 

10. ACP-H-S!l3 16.2 9.8 7.3 6.0 '.2 8.1 8.0 8.1 

U. ACP-fl-sb3 )2.4 10.0 

I 

9.6 9.0 8.7 '.S 8•• 9.3 

I 

12.H8nUi'an 8 8.3 6.8 S.3 I 1.0 1.' S.O I 6.1 

7.' 

13. Momron 16 1.7 8.6 1.0 8.0 9.1 '.0 I 

I 

15. SiMa1n S 2.0 

, 

3.1 6.0 1.0 9.~ 1.0 

14. }lonuron 32 7.3 9.3 8.3 1.0 '.S 8.1 8.S 

¥:. St.-Un 10 '-.8 7.0 8.3 

I 

la.) '.0 1.0 6~1 

17. Siuai.n 20 S.5 8.3 ,.$ S.s 9.6 ,.) 7.1 

18.AQ-H-S69 10 6.S S.7 3.0 1.0 8.1 ,.S • 

I 

6" 

U. ACP~-S69 20 6.7 5.0 3.0 7.' '.6 '.3 6.7 

20. ,wt.n1 20 6.7 6.0 3.0 ,.) '.1 '.0 6.7 

n. A~17 9 7.S 1.8 4.7 I 6.0 It.) 

'.3 

I 

So' 

~. J\Cf~17 • Sium. n , .2.5 9.0 6.3 4.7 j 8.0 6.3 I 

'.3 1.1 

~:t lJlIIok 0.0 0.0 0.0 0.0 0.0 0.0 I a.D 

\ "'on &DalApon 20 &21.3 7.8 8.3 S.3 I S.7 8.5 

"" 1.1 

~ 

o -no eoM.l'ol Test applied 8 l{A7 1956 

N 

s 10 • c~le\e kill 

~.

463 

Table II. NEWYORKSTATE 

GUARDHAILVEGl!."I'ATION CONTROLTEST 

POPULATION DATA 

Before Treatment - May 8; 1958 After Treatment - October 3. 1958 

-------------..-.-------------------------~------------ ---------------------- 

Tmt.# Grass Broadlea! ; Grass Broadlea! 

------------------------------------------~------------------------------------ 

1.* orchard. quack. dandelion, carrot.; orchard. quack. bedstraw. milkweed. 

Kentucky blue, aster, bedstraw, . foxtail butter & eggs, 

timothy, rye. mullein. dock. bouncing Bet 

tall fescue butter & eggs 

2. quack. orchard. 

Kentucky blue. 

timothy, rye, 

tall fescue 

dandelion, carrot, I quack, orchard, 

aster, bedstraw, ,foxtail, 

mullein, dock, barnyard; 

butter & eggs, 

bouncing Bet 

milkweed, 

butter &: eggs, 

ash seedling, 

bouncing Bet 

3. quack, orchard, 

Canada blue. 

Kentucky blue. 

tall fescue 

geranium. dock, 

bouncing 

dandelion 

Bet, 

butter & eggs 

I 

quack, 

foxtail 

orchard, 

bouncing 

milkweed 

Bet, 


rye, 

Kentucky blue 

5. 

6. 

7. 

8. 

quack. orchard, 

Kent-icky blue. 

tall fescue 

quack, orcha rd, 

rye, 

Kentucky blue 

quack, orchard, 

Kentucky blue, 

rye 

quack. orchard 

Kerrtucky blue, 

Canada blue, 

rye 

dandelion, dock, I quack, orchard, 

bedstraw, hardrock , oJater 

chickweed, carrot, I foxtail 

parsnip, clover, barnyard 

bouncing Bet. 


yellow rocket 

dandelion, 

bedstraw. 

bouncing 

dandelion, 

bouncing 

Bet 

Bet. 

dandelion, 

geranium, 

bouncang Bet, 

dock, sorrel 

dandelion, dock, 

carrot. yarrow, 

bouncing Bet 

sorrel 

1 foxtail, 

I barnyard, 

, water 

I 

I orchard, quack, 

foxtail, 

Canada blue, 

foxtail 

quack 

quack 

*Treatment numbers refer to treatment list in table I. 

dock, milkweed, 

pigweed, 

bouncing Bet 

bouncing Bet, 

milkweed, dock, 

bouncing Bet, 

milkweed, 

bouncing 

pigweed. 

milkweed, 

Bet,

Table II. 

(cont.) 

-------------- 

________________ Before Treatment - _ l'!ay ___ 8, 1958 ,_0' __ - AftE'r Treatment - October 3, 1958 

Tmt.# Grass Broadlea! : Grass Broadleaf 

------------------------------------r-------------------------------- 


rye, timothy 

KeI/,tucky blue, 

Canada blue, 

dandelion, sorrel,' orchard, quack, 

chickweed, dock, . foxtail 

burdock, henbit, I Canada blue, 

bedstraw, thistle,. M~hlenbergia 

yellow rocket, 

plantain 

ragweed, 

pigweed, 

bouncing Bet, 

dandelion, 

burdock, thistle 

10. orchard, quack, 


timothy, 

Canada blue, 

11. orchard, quack, 


rye, timothy, 

tall fescue, 

Canada blue 

dandelion, 

bouncing Bet, 

bedstraw, dock, 

butter & eggs 

yarrow, 

wild geranium 

I 

orchard, 

foxtail, 

barnyard 

quack, 

dandelion, carrot,' foxtail, quack, 

bouncing Bet, dock~ 

sheep sorrel 

butter & eggs 

bedstraw, yarrow, , 

chickory, burdock, 

wild geranium I 

milkweed, 

bramble, 

sheep sorrel, 

pigweed, bramble, 

milkweed, 

bouncing Bet, 


rye, timothy, 

I~entucky blue, 

tall fescue, 

Canada blue 

bedstraw, mint, 

geranium, yarr01', 


sorrel, 

bouncing Bet, 

butter & eggs 

I foxtail, quack, 

orchard, 

I barn~ard, 

Canada blue 


bouncing Bet, 

milkweed, 

13. 

15. 

quack, orchard, dandelion, dock, ! quack, orchard, bouncing Bet, 

Kentucky blue, mallow, oxalis, water, foxtail, milkweed, dock, 

tall fescue, wild Geranium, barnyard, thistle, 

bouncing Bet, sheep sorrel, 

butter & eggs 

quack, orchard, dandelion, dock, quack dandelion, 

rye, carrot, bouncing Bet 

Kentucky blue, bouncing Bet 

tall fescue 

quack, orchard, dandelion, dock, I quack, orchard, thistle, 

Kentucky blue, carrot, yarrow, Kentucky blue, wild geranium, 

tall fescue bouncing Bet, I Canada blue, milkweed, 

Huhlenbergia sheep sorrel, 

foxtail bouncing Bet

465 

Table II. 

(cont , ) 

Before Treatment - May 8, 1958 

After Treatment - October 3, 1958 

Tmt.# Grass Broadleaf Grass Broadleaf 

16. quack, orchard, dandelion, dock, quack, orchard, thistle, 

Kentucky blue, aster, Kentucky blue, bouncing !:let, 

Canada blue) bouncing Bet Canada blue, milkweed 

tall fescue 

17. quack, orchard, horsetail, quack, milkweed, 

-Kentucky hLue , bouncing Bet l1uhlenbergia horsetail, 

Canada blue,rye bouncing Bet 

18. orchard, rye, mullein, yarrow, , orchard, foxtail, milkweed 

quack, butter & eggs, , Muhlenbergia 

tall fescue, dandelion, dock, 

Kentucky blue, wild geranium, 

Canada blue bouncing Bet 

19. 

orchard, quack, 


tall fescue, rye 

yarrow, 

bedstraw, 

dandelion, 

carrot, 

dock, 


wild geranium, 

bouncing Bet 

I foxtail, panic, 

yellow 

rocket.,.: 

20. 

orchard, quack, 


tall fescue ~ 

Canada blue 

yarrow, dock, 

bedstraw, 

dandelion, 

carrot, burdock, 

yellow rocket, 


sorrel, 

bouncing Bet 

I foxtail, orchard, 

love 

dock, 

prickly 

lettuce 

21. 

quack, orcha rd , 

Canada blue, 

tall fescue 

bouncing Bet, 


foxtail, 

orchard 

quack, 

bouncing 

Bet, 

22. 



Canada blue 

bouncing Bet, 

dock, yarrow, 


wild geranium 

foxtail, 

quack 

orchard, 

milkweed, 

bouncing 

Bet.

466 

Table II. 

(ccnt , ) 

Before Treatment - ~~y 8, 1958 After Treatment - October 3, 1958 

Tmt.# Grass 

Broadleaf 

Grass 

Broadleaf 

check 

23. quack, timothy, 

tall "fescue, 

orchard, rye, 


Canada blue, 

dandelion, 

carrot, 


bedstraw, dock, 

chickory,aster, 


sheep sorrel, 

bouncing Bet, 

yarrow, burdock, 

horsetail 

orchard, "quack, 

I 

foxtail, 

panic, 

crab, 

rye, 

tall fe scue, 


Canada blue, 

Muhlenbergia 

milkweed, dock, 

bouncing Bet, 

24. quack; orchard, 

tall fescue, 


Canada blue, 

Elr;l:meif!g:Bet 

lta"l1udlion, 

dock, yarrow, 


butter & eggs 


foxtail, barnyard, 

milkweed, 

sheep sorrel, 


bouncing Bet, 

________________________________________ 4- ~ _ 

Weed species as recorded in this paper: 

1. quack - Agropyron repens 

2. orchard - Dactylis glomerata 

3. tall fescue - Festuca arundinacea 

4. Canada bluegrass - Poa compressa 

5. Kentucky bluegrass - Poa pratensis 

6. Rye - Lolium pererne 

7. Timothy - Phleum pratense 

8. Dandelion -Taraxacum officinale 

9. Wild carrot - Daucus carota 

lO.Sorrel - j{umexacetosella 

11.Bouncing Bet - Saponaria officinalis 

12.Dock - Rumexcrispus 

13.Bedstraw - Galium spp. 

14.Chickweed - Cerastium vulgatum 

IS.Wild geranium - Geranium nolle 

16.Mullein - Verbascum thapsus 

11.~'ild parsnip - Pastinaca sativa 

18.Burdock .. Arctium lappa 

19.Henbit .. Lamiumamplexicaule 

20.Thistle - Circium arvense 

2l.Plantain - Plantago spp. 

22.Chickory - Chichorium intybus 

23•BUtter' & eggs,,:-·,Liflaria.' vulgaris 

24.Mint - Mentha sPPo 

2S.Hallow - Malva neglecta 

26.Horsetail rush - Equisetum arvense 

2?Yarrow - Achillea mille folium 

28.CIover - Trifolium spp. 

29.Poison ivy - }mus radicans 

30.OXalis - OXalis stricta 

31.Wild aster - Aster spp. 

32.Bramble - Rubus spp. 

33.Foxtail - Setaria spp. 

34.Milkweed - Asclepias syriaca

( ( 

Table III. 

LATESUHMER APPLICATION OFGUARDRAIL TEST 

Connecticut 

Treatment 1b/A 1 month 3 months 2 months 3 months 

, 

-----------~--------------~-----~--~-----------------~--------- - - ----- -- --. --- -- - - - - - - - - - -- - - - - - - - - - -- 

AV G BL AV G BL AV G BL AV 

-.-----------------------------------------.-------------------------------.---------------------------- 

10 Dalapon J. 2,4-D *21.3.,.2 I 7.0 7.5 6.5 7.0 6.0 7.0 6.5 I 4.3 1 2.6 

2. Da1agon,. 2,4-D*21.3"2 I Ii 

'I' Lmazd.n "'$, 5.5 8.0 8.0 8.0 , 8.3 8.0 8.2 8.6 5.0 6.3 

3 9 ACP-H-5h2 2.8 I 2.5 2.5 5S 4.0 3.3 4.3 3.8 2.2 5.0 3.6 

I' 

4. ACP-M-542 5.6 3.0 4.0 5.5 4.8 6.6 8.6 7.6 ! 6.8 6.0 6.4 

5. ACP-M-543 J~.05 I I II 

4.0 4.3 4.2 I 1.6 4.0 2.8 

6. ACP-~i-543 8.1 

I I fi 6.3 7.0 6.6 I 4.3 3.0 3.7 

7. ACP-M-569 5 I 3.0 I 3.0 7.0 5.0 Ii 3.5 7.5 5.5 I 2.0 5.0 3.5 

8. ACP-M-569 10 i J.5 5.5 8.3 6.9 I! 7.0 8.5 7.7 . 3.6 3.0 3.0 

·9. Amitro1 10 I 2.5 3.5 8.0 5.8 3.5 8.0 58 ' 2.8 3.0 2.9 

I' 

10. ACP-M-673 5 4.5 4.8 8.0 6.4 0 0 o· ! 

0 3.0 1.5 

li. ACP-M-673 10 1.5 I 2.0 5S 3.8 II 1.0 1.0 1.0 I 0 4.0 2.0 

12. ACP-M-673 20 ! 1.5 I 3.5 6.0 4.8 q 1.5 1.0 1.2 I 0 4.0 2.0 

13. ACP-M-674 5 I 0.5 I 0 0 0 0 1.0 0.5 I 0 4.0 2.0 

" 

~. ACP-M-674 10 I 0 i 0 4.0 200 I. 1.0 3.0 2.0 I 0 3.0 1.5 

15. ACP-H-674 20 , 7.0 , 2.0 5.0 3.5 

16. 14..673.. M-569 10+$ 

II 

8.0 . 4 00 7.0 5.5 3.5 5.0 4.8 I 2.0 2.0 2.0 

17. N-674 .. ;1-569 10.;.5 I 9.0 i 6.0 II 

8.0 7.0 1+.0 7.:' 5.7 J 1.0 4.0 2.5 

18. ACP-N-659 19.2 I 5.5 ' 7.0 8.0 7.5 'i 5.5 7.0 6.2 i 2.3 3.0 2.7 

19. ACP-M-660 21.7 I 6.5 I 8.0 8.0 8,,0 I' 8.5 5.5 7.0 I 3.0 2.5 2.8 

20. H-659 '" 11-673 19,2 L5 j 4S ! 3.0 7.5 5.8 

Ii 

6.5 7.0 6.8 1.0 3.0 200 

21. U-b)9 .. li-674 1902...5 I 4.0 I 2.0 4.0 3.0 7.5 600 6.7 3.0 1.0 2.0 

I 

22. M-673'" L-638 10 "'2 IS' 3.0 7.0 5.0 0 2.0 1.0 I 0 1.0 0.5 

2l' N-674 + L-638 10 .,.2 11.0 I 2.0 6.0 4.0 

fl 

0.5 2.5 IS ' 0 2.0 1.0 

2 • Dalapon ester I I . 

., 

I 

+ Silvex 23 "'31 ! !I 7.0 7.0 7.0 , 6.5 4.0 5.2 

*Da1apon14.2 .,. 2,1+-D2 Ohio +- 

0- 

-ọ 

Ohio

468 

Discussion 

and Conclusions: 

Dalapon combination::;: 

In NewYork dalapon gave good to excellent initial control of grasses, 

with control declinipg through the summer. The addition of 2,4-D gave good 

control of annual weeds, but did ~t contrel milkweed or bouncing Bet. The 

addition of monuron or sirnazin to dal.apon-Zylr-D mixtures improved the control 

o~ grasses and broadleaf weeds. By October, grass regrowth covered 50%of 

the dalapon-2,4-D plots. 

In Connecticut, late summerapplications of dalapon-2,4-D gave good grass 

and fair broadleaf weed control for three months. In Ohf.o, weed control was 

fair' to good after two montHs and fair to poor after three months. The 

addition of simazin gave good weed control for a longer period. 

In Ohio" Ii mixture of sdLvex and diethylene gl~ool bis 2,2-dichloropropionate 

gave good control of grass and broadleaf weeds after two months and fair 

control after three months. Control of tall fescue was superior to the control 

of blue grass and red fescue. Moderate to sev.:;re damage resulted from 

the treatment's washing onto untreated areas. 

Amitrol combinations: 

ACP-M-542,a 1:3 combination of arnitrol and simazin, gave good to excellent 

control of grass and broadleaf weeds throughout the summer in NewYork. A 

rate equivalent to L4 lb/A amitrol and 4.2 lb/A simazin gave an average of 

80%control throughout the growing season. Th:i,streatment gave acceptable 

control within the first month and maintained this control throughout the 

season. Higher rates 'gave control approaching complete eradication of plant 

growth. The 11.2 and 22.4 lb/A rates gave excellent control of bouncing 

Bet with zero to',% regrowth. The c.ontrol of bouncing Bet was superior to 

that acheived with 20 lb/A of amitrol or 20 Ib/Aof actual simazin alone. 

Plots treated with similar amounts of sirnazi.n alone gave approximately equal 

vegetation control by October, but initial control dur~ng the first two months 

was less effective~ Plots treated with ACP-M-542also had more effective 

control of qnackgrass,Cimada thistle, milkweed, bouncing Bet and curly dock 

than did plots treated with sirnazin alone. Late aummerapplication of ACP-~1 

542 in Connecticut and Ohio was less effective tha~~arly summerapplication 

in NewYork State •. In Connecticut 5.6 Ib/A of ACP-t~542 gave only fair 

control of grass .anc .bl'oadleaf weeds after three months, and in Ohio gave good 

control of grass and 1:?roadleaf weeds after three months. 

In NewYork, ACP-!1··543,a 1:4 combination of amitrol and monuron gave excellent 

initial control of all vegetation at rates or 8.1, 16.2 and 32.4 Ib/A. Weed 

controI One.month after application wassuperiQr to 8 similar rate of monuron, 

but at 2i months, weed control with monuron and ACP-M-5L3was approximately 

equal. In OhiO, ACP-M-543gave good general weed control after two months 

with fair to poor co~trol after three months. Monuron alone ~ave good initial 

weed control which improved to excellent weed control after 2~ months in New 

York. with a sli~ht decline in de~ree of weed control after S months.

469 

ACP-M-617, a 1:3 combination of amitrol and sodium perrtacbkcrcpbenate gave 

good initial weed control which deteriorated after several months. Broadleaf 

weed control was fair to good, becoming excellent in October~ - The 

addition of simazin to this mixture gave increased initial grass control 

but did not significantly affect the vegetation control later in the season. 

Amitrol alone at rates of 10 and 20 lbl k gave good initial grass control and 

- good to excellent initial breadleaf '!reed cor.trol in NeW-York. At the treat 

,T.ent rates, all perennial grasses werecontrolled, but late summer germination 

permitted foxtail to invade the plots in September and October. Broadleaf 

weed control was excellent after five months. T-here were several stunted 

milkweeds in the 10 lb/A plot of ACP-M-569, the liquiO.!unitrol formulation; 

some newly germinated yellow rocket in the rosette stage in the 20 Ib/A 

ACP-M-569plots and several dock and prickly lettuce plants in the rosette 

stage in the 20 Ib/A amitrol treatnent. Rates of five and ten Ib/A of amitrol 

gave good breadleaf weed control in Connecticut after' three months but only 

fair to poor grass control. In Ohio, equal rates ofamitrol gave similar results. 

Fenac 

Applications of the sodium salt and-amide .f01'l1lU.1.ationsof 2 j3,6-trichlorophenylacetic 

acid (Fenac ) indicate that initial results with -these materials are 

very slow to appear and that as other research has indicated, three to four 

months are necessary for these materials-to-give weed control when applied 

during the growing season. Five pounds of the sodium salt of fenac gave good 

broadleaf weed control in guardrail tests in Connecticut, but poor to fair 

grass control. After three months, the 10'and 20 Ib/A rates were not more 

effective than the 5 Ib/A rate. Results on this testYDuld indicate that the 

amide formulation is slower in reaching its peak activity than the sodium 

salt formulation. In Connecticut,.. combinrtions of fenac with the sodium salt 

of 2,2.3-trichloropropionic acid and amitrol showed fair to good initial 

activity with decreasing grass corrtrc'l.-aa the season progressed. 

Time of application: 

Based on the results of this test •. itwouldappear-that late spring or early 

- summer is a more satisfactory time of application for- guardrail weed control 

materials, since early application of most materials in NewYork State gave 

better weed control than late summer application of the same materials in 

-- Connecticut and Ohio. 

Second year 

evaluation: 

Each of the treatments applied in this test will be evaluated in late spring of 

1959 to determine the amount of carry-over of chemical activity in the second 

season. Also. an effort will be made to find treatments and rates which will 

maintain the treated areas in a vegetation free condition at low cost following 

initial control with high rates of residual materials.

470 

General 

observations: 

It appears that treatllEnt of highway guardrail vegetation created several 

problems. First, there is the danger that weed control materials may be 

washed down the side of fill sections, thus damaging vegetation and possibly 

creating an erosion problem. When the difficulties of establish~ng a grass 

cover are considered, it is questionable whether providi,ng vegetation control 

under guardrails justifies the possibility of injuring the cover. Also, 

certain treatments control the perennial population but allow the treated area 

to be invaded by large unsightly annual grasses and broadlea! weeds such as 

foxtail, barnyard grass, lambsquarters, pigweed, ragweed or kochia. Many 

treatllEnts do not control deep-rooted perennial weeds such as milkweed, Canada 

thistle, horsetail rush or bouncing Bet. Because no one chemiaaa:~ppear8'to have 

a sufficiently broad spectrum to control all weed species at economic rates, 

a mixture of chemicals is usually most suitable. 

For example, in this test the combination of a translocated herbicide, amitrol, 

with a residual herbicide, simazin, appeared to utilize the advantages of each 

material. Amitrol produced an early knockdown of plant.growth and controlled 

such perennial weeds as milkweed and Canada thistle, while simazin prevented 

the germination of new weeds p Because amitrol gave initial knockdown and 

control ot problem weeds, less simazin was necessary for seasonal weed control. 

Aside .from the lower cost, the reduced amount of simazin made erosion damage 

less likely on cut and fill sections. 

:! 

WEED CONTROL AND OUR PROBLEMS IN VIRGINIA 

471 

E. W. Turner, Associate Landscape Engineer 

When Mr. Iurka requested that I take part in the program, I, 

having very little experience with weed control, was naturally 

hesitant in agreeing to do so. However, in talking of the problems 

that we have we may receive answers that will be of help to 

others. 

To begin with, a number of years ago we met with representatives 

of pUblic utility companies, tree trimming companies, chemical 

companies, and others in order to see if we could not arrive 

at a mutually satisfactory working agreement. As a result it was 

agreed, in the hope of minimizing complaints from the pUblic, 

that spraying would be limited to the selective spraying of material 

not over three feet - or one season's growth - in height. 

Even this brought complaints. Soon we were receiving letters 

and telephone calls regarding "browning" as a result of spraying. 

In most instances the spraying was not within our right of way, 

but, even then, it served to show that we could expect complaints 

whenever we did spray on our own right of way. 

This resulted in our Commissioner issuing instructions on 

August 25, 1954 to the effect that: 

1. A dormant spray for woody plants is not to be used on 

any vegetation over three feet in height. 

2. Foliage spray is not to be used at all except with 

written permission of the Chief Engineer, after approval 

by the Commission. 

3. Weeds could be sprayed only when less than three feet in 

height. 

4. Any trees, etc. over three feet in height must be cut 

down to below three feet in height before spraying with 

any herbicide. 

This was again brought up when shortly after one of our men, 

who was promot~d~o Resident Engineer, sprayed all brush along 

the roadsides in his area. The owner of a considerable amount of 

land in this area was most vigorous in his complaint. 

That is one problem. Another, and one usually prevalent in 

highway departments, is that of financing a program of spraying - 

- ..1_ ~ 

,- .... ...s.~ 

_

472 

New funds become available in Virginia on the first of July 

of each year~ That is probably rather late to start a program 

and, in addition, those in charge of funds - and any spraying 

done would be paid for from regular maintenance funds - are 

afraid that we will have another bad winter. Every spring - regardless 

of the type of winter - there is always a lack of funds. 

In some instances, we are receiving help from County Boards 

of Supervisors that request that we use chemical w~ed and brush 

control. In such cases ,. the Resident Engineer will usually go 

along with a program of spraying - at least to a limited extent. 

So, the second problem is one of economics.... "If we· can. find 

away to· eliminate complaints, how can we convince those that 

~ontrol the funds that it is economically feasible to institute 

a program of spraying? . 

Twenty years ago, it was a very rare thing to find a paved 

ditch along our roadsides. We, in the Landscape Division, realized 

that we would never ~ecure satisfacto~y control of roadside 

erosion unless highly erodable ditches were paved. In order to 

prove the value of such ditches, we began to .uae a small amount 

of the very limited landscape funds to pave some of the worse 

ditches. This convinced our Maintenance Engineer and he gave us 

a few thousand dollars a year to expand our program. Now it is 

standard practice for all ditches that may be sU8ceptable to 

serious erosion to be paved during construction. ~e have been 

working on demonstration areas and hope to convince our Resident 

Engineers of the value of chemical weed control. 

It has been claimed, and rightly so, that the proper use of 

weed control chemicals can not only produce a better appearing 

turf, but it will also reduce the cost of mowing. This is particularly 

true of the southeastern part of the State where wild 

onions spring up at the least sign of warmth. It would also be 

true in the areas where we have a nearly pure stand of bluegrass. 

However, the main grass that we use now is Kentucky 31 Fescue. 

This, as you know, is a tall growing fescue .and develops so rapidly 

that, if you have a good stand, it outgrows the weeds. Saving 

mowing costs as an argument for weed control would not help 

much in such instances. 

One source of weed infestation is from the topsoil applied 

to roadside areas. Frequently, this soil is full of weed seed 

which establishes weed growth before the turf can get a good 

start. On occasions we have been glad to have even this - but 

not very often. We would like to know of a practical way to prevent 

this weed growth. Should we treat the topsoil before it is 

taken up to be stockpiled? Is there some way that we can treat 

the topsoil after it has been applied to the roadsides and not 

delay the seeding operations?

We, 

farmland 

perience 

fields. 

of course, agree that many weeds spread to adjoining 

from the roadsides. I would like to hear of your exwith 

weed spreading to the roadsides from adjoining 

are: 

Some of the chief causes of excessive weed growth in turf 

1. Improper number and time of mowings. 

z. Impoverishment of the soil. 

3. Deficiency of available water 

4. Wet, impermeable, or acid soil 

5. Grass varieties not well adapted to environmental conditions. 

Some of these, such as a lack of water, we cannot control. 

However, would it not be possible to try to correct some of the 

other conditions that promote weed growth? In many of the bluegrass 

pastures of Virginia the presence of broom sedge is evidence 

of depletion of soil fertility. Experiments conducted some years 

ago showed that an application of 200 to 300 pounds of acid phosphate 

every five or six years kept this weed in check. 

In summation, we admit that we have not made much progress 

in weed control. We need help in finding ways to sell a complete 

spraying program; we need help in mapping out just what should be 

included in such a program and, with the increasing demands from 

public utilities, we need to work out a policy toward utility 

line spraying that would be most satisfactory to all concerned.

474 

REDUCINGSTATE HIGHWAYMOWINGCOSTSWITHCHEMICALSIN MASSACHusETTS 

Joseph L. Beasley 

Highway Landacnpc Supervisor 

Massachusetts Dopartment of Public Works 

Northoast Woed Control ConferOl1Co 

January 7-9, 1959, New York, N. Y. 

Weod control is importcnt in ell categories of Roadside 

Haintunanco. Along a aoc ondnr-y highway, or "country 

road," wo genorally like to keep tho roo.dside as close to 

its natural state as possiblo, consistent with safety and 

efficient mainteno.nce. In direct contrast is the industrial 

or commercial highway whore boauty compotes with utility 

and efficiency. The stato highways of Massachusotts full 

in butweon thesotwo oxtromes. The peoploof Massachusotts 

insiSt on well-groomod highways, in keoping with tho threecentury 

tradition of having a village groen in the middle 

of every town. But at the same time, their YOonkeethrift 

dbmnnds that this scenic beauty be Oochieved at the lewest 

possible cost. 

As 0. result, the State Depo.rtmont of Public Works has 

16,000 ncres of roadside grass to mow overy year along our 

pro sent 2,250 miles ef sto.te highwc.y. Tho 90 mUes presently 

under construction will add anothor 1,800 acres of roadsidps. 

In 1958, the bill for mowing tho ,16,000 acres was $700,000, 

en average of $44 per acre--and this was tho lowost mowing 

cost for any year to date, evon with continually increasing 

road mileage and continually rising wage rates. 

Since 1951, Mcssachusotts has boon using and oxperimenting 

with chemical weod killers in an offort to reduce mowing and 

maintonanco costs. We have used 2,4-D, 2,4-D+2,4,5-T, 

Maleic Hydrazide, Telvar D. W., Diuron and Uroabor. All have 

been used with varying degrees of SUccess. We have learned 

that each has its place in maintenance as a useful teol. Herbicides 

in themselves are not a "cure-all" for roadside maintenance 

problems. When properly used, however, in combination 

with other roadside eperations, the result is 0. more ploasing 

readside appearance at a considerable saving financially. 

Massachusetts is n pioneer in tho field of mowing grass 

by centrcct. After a numbor of trials and revisiens, we new 

feol that we have the bost centract mowing specificatiens 

in tho ceuntry. It is this cembination of mowing by contract 

cnd the spraying of horbicides that has effoctod our greatest 

reduction in mowing costs. Thorofore, in ordor te proporly

475 

and economically maintain the grassed aroas of the future 

450 miles of interstate highway along with a large portion 

of tho 2250 miles of our State highway system, it will 

profit us to concontrate even further on our herbicide 

program. 

These mowing contracts call for a maximum of eleven 

(11) cuttings on certain grassed areas and a minimum of 

one (1) on other grassed aroas. 

Item One (l)--Lawn Type Mowing--Eleven Cuts (11) per 

season--includes: 

Median Strips, Bowl Areas, Dividing Strips at Ramps, 

Traffic Islands and Rotaries. 

On the above areas the total width, or on wide median 

strips and bowl areas, a maximum width of 30 feet from all 

roadways is mowed undorthis itom. 

Item Two (2)--Roadside Hay Mowing--Five (S) cuts per 

season--includes: 

A minimum width of 15 feet·of grassed area on the 

roadside ~ not ~ 5 feet but always including this 5 

feet on cut slopes and the p01'tion remaining uncut from 

Item 1 in all areas outlined from Item 1 mowing. 

Grass directly in front and in back of guard rail 

is mowod so that the guard rail is clearly outlined. 

Item Throe (3)--Hay Mowing--One cut per season--includes: 

All grassed areas not covered under Items 1 and 2. 

Contracts for certain secondary routes call for Items 

·2 and 3 only. 

Note: I have a copy of a currant Contract Mowing Proposal 

with me that is available for your inspection. 

Our first use of chemicals along our roadsides was 

directed against poison ivy, at the time an Qxtremely 

serious problem. Through the use of 2,4-D and 2,4,S-T, 

this problem has been practically eliminated. This fact 

not only has boen reassuring to tho 3,000,000 pooplo who 

enjoyed our 300 roadside rest areas last season, but 

greatly reduced the lost "man hour-s" of our department 

employeos who are engaged in roadside work. 

The Massachusetts Departmont of Public Works has been making 

valuablo contributions to highway safety with the aid of 

chemicals, (2,4-D and 2,4,5-T, 50-50 concentrates combination 

low volatile esters) by making a concerted effort to increase 

sight distance on our highways. These horbicides also assist

476 

in controlling brush at our roadside rest areas and vistas, 

behind guard rails and in our selective clearing program. 

Not only has the general appearance of our roadsidos 

beon greatly improved but we feel that clean roadsides 

are a major factor in highway safety. 

Then we began the selective control of ether weeds 

and havo experimented with 2,4-n and M-H-4oin our constant 

effort to reduce the number of annual mowings. 

Unfortunately, we haven't found any chemical lawn mowers 

as yet. But we have found that zomo weeds grow a good 

deal fastor than grass, particUlarly in dry years. 

We must then,c:ontrolthese weeds and insure a uniform 

growth of grass, which, even though above normal 

in height, will still pr-E)'sont a satisfactory appearance. 

We have tomporarily discontinued the use of M-H-40 

until further technical information is available. . 

However, through a combination of applying 2,4-D to eliminate 

dandolions, ragweed, and other succulent wood growth 

on our median strips, and by revising our specifications 

for contract mowing, we have been able to reduce tho 

number efmowings on Item 1 from 15- cuttings por year to 11. 

Reducing the amount of hand work necessary in roadside 

mowing has resulted in mere efficient use of mochanical 

mowers. In 1958, we had 25 mowing contracts for 500 miles 

of highway, invclving 7,000 acros of roadsido. In 1959, 

we expect to expand this program. It was a great day when 

we were able to write into these mOWing contracts: l~hiB 

contract docs not require trimming at guard rail locations, 

since those areas will.be treated with chomicals ••• eliminating 

all vegetative gr-owt-h ••• " 

It is tho intention of the Department to treat all 

roadsido, median strip, ramp road and traffic island grassod 

areas, subject to contract mowing, with weod control chemicals 

for tho elimination of such weed growth. Two applications 

of chemicals are planned for thoseaBon. As these 

aroas may not be mowed for 72 hours bofore treatment or 48 

hours after troatmont, it becomos nocessary to coordinato 

theso two operations so as te insuro·th~ least inconvenience 

to all parties concerned and produco the most profitable 

results. 

Our state highway system has approximately 900 milos 

of guard rail. Ono hand trimming along a mile of guard 

rail may take oight man hours, and the job may havo to bo 

done fivo times per soason. With this chemical program, 

"- 

wo can go along the guard rail withe. powor sprayer 

covering a band two foot wide at a rate of ono and ono-half 

.L._ J..~ .. _ ......... ., .............. ,.._ ""',...,,_ 11 f-'A)'t"\_f'nl""l+' h~n.n ~ mil;) lona fR about ...

477 

a quartor of an acro, so four miles of guard rail means 

an acre of spraying. In othor words, one hour of soil 

storilant spraying, at two miles per hour, eliminates 

eighty hours ef hand trimming. And the job is done 

onco fer tho wholo soason. Our present program calls 

for troating a two-foot stip along all our guard rails 

in this way, with a follow-up treatment where nooded a 

yoar or two after tho first application. 

Wo nowhavQ had five years' experionce with this 

specialized use of chemica1s--beginning with a small 

trial in 1953 along guard rails and in tho joint at curb 

facings •. Tho curb treatment romained effec ti v o for one 

year, and the guard rail treatment for over three years. 

By 1957, we had treated about 420 mi10s of ~uard rail--or 

over 100 acres, and in 1958, we have done 745 milos, or 

about 185 acres. We also followed up some ef tho oar1ier 

treatments with "Uroabor" for hard-to-reach locations, 

and places wo had missed entirely. We have learned that 

soil stori1ants of the granular type play an important role 

in the roadsidedovelopment program. 

Tho soil steri1ant program has boon so successful 

on guard rails that we are adopting the same kind of treatment 

to eliminate hand trimming around polos, ledges, 

delineators, curbing, piors, abutmonts and othor structures. 

Wo are also trying this approach for weud control in watorways, 

drainage ditches, gravel sidowalks, and along fences. 

In othor words, this program is boing carried on 

whorever chemical control can be omployed without hazard 

to trees or desirable plantings. 

I montioned the possible hazards involvod in the use 

of chemical woed killers. We have to remember that these 

compounds ero intended to kill plant life, and that wo 

must obsorve the proper precautions ~o be sure that we 

kill only t.b.:Iplant life of which we want to be rid. In 

treating nearly 900 miles of guard rail in Massachusetts 

with soi1-sterilan~ type herbicides, I am happy to say that 

wo havo had no mishaps when the maturial was properly applied. 

We have had a few instances of damage to turf eutside 

the troated area, and 011 of these have boon. traced to 

faulty application. In somo cases the oporetor turned 

the spray inte areas that should not have boen sprayod. 

In othor .si tuations we have found evidence of run-off, 

and this hazard desorves spocial attention in highway 

weed control. The absence of curbing, guttors and culvorts 

may direct drainage and"run-off in such a way as to croato 

problems. Establi~hedcovor of grass and wQeds in and 

around tho treated area is an important factor in holding 

the chemical whoro it is sprayod. Pavoment v10se to tho

478 

treated area prQs~nts n special problem. For examplo, 

if you accidentally spray your wood killer mixturo on 

~avom0nt, thoro is no soil to hold it and tho ohemicul 

merely dries on the surfaco. ~ the first good rainstorm 

can wash it ovor to an area not intendod for 

trvatment. 

We havo confidenco in ~hemical weod killers, and it 

is to their crodit that thoy are so effoctive. However, 

we must be careful with them. 

We have held many meetings in our various districts 

to instruct engineers nnd foromon in tho preper uso of 

those matorials, and to exorciso prop or precautions in 

applying thom. Wo want them to accopt chomical weod 

killers as a tool for thom to use in its proper place 

in highway mnintennnco--just as thoy uso sand, salt, 

patching materials, or snow plows for their prop or 

purpoG&. 

The variety of chemicals available, and tho spocialized 

jobs of oach, havo placed a premium on expert knowlodgo in 

selocting and applying them. In gonoral, it appears that 

centractors and ownors of spraying oquipmont should seo 

to it that their personnol bocome moro familiar with tho 

various horbicidos, as thoy relate to highway and roadsido 

maintonanco work. Wo are trying to train our local foremen 

se that they can de many of tho little jo~s with chemical 

wood killers. The soil-storilant work, for example, can 

be dono almost any time of year, with availablo manpower- 

so it provides till-1n work fer a small crew instead of 

seasonal work for large crews. If applications nre made 

beforo growth starts in the spring, then summer work on 

the treatod area is eliminatod entiroly. In other words, 

you can kill weeds before they start to grow. 

Looking ahead a littlo bit, we expoct to continuo 

and intonsify our presont program, with the cost of mowing 

as our primary financial yardstick. Wo want grass along 

our roadsides. But wo are compollod to admit that we canlt 

afford tho lUxury of having grass adjacent te tho base of 

guard rail posts, signposts, etc., whero hand cutting is 

required. We havo a long way to ge bofore wo shall make tho 

best uso of the combination of chomicals and mechanical 

maintvnanco which oro now available to us, and wo have a 

long way to go in training our own people whe actually have 

to gut tho work dono. It has takon soven years to arrive 

at our present program but furthor innovations will como 

more quickly. We think our plan is basically correct l as 

tho intent is to maintain roadsides as our citizens want 

them; we hope to make this basic plan moro effectivo 1 by 

keoping infermed on new dovelopmonts and now ways of doing 

thinas.

Www~lcomc th~ interost and technical help of 

commercial companiGs, and we foel sure that as the 

public undor-s t ands wha t this kind of program moans ., 

to them, we can count on thoir acooptance and support 

of what wo are doing. 

479

48() 

CUHRENTHERBICIDE1tlORKIN NE',J YORKSTAl'E 

BY 

Andrew M. Ditton 

Senior Landscape Architect 

New York State - Department of Public VJQrks 

.cew '{ark State has completed its second year in a herbicide 

pro&ram on the state highways. This program consists of (1) 

broadleaf weed control to reduce the number of machine mowings required; 

(2) chemical mowing of gUide rail, posts and signs to 

01iminate all mowing from these areas where hand mowing has been 

required; (3) brush control to eliminate undesirable brush growth 

from the highway right of way; and (~) poison ivy control to eradicate 

poison ivy from the right of way. 

Herbicides have been tested and used to a limited extent 

along New York State highways for ten or twelve years. This pro~ 

gram is on a larger scale than formerly. Because the requirements 

of roadside maintenance with herbicides are unique, the 

chemicals and the application techniques are being modified as 

experience is gained. 

Highway maintenance engineers are generally enthusiastic 

with the results obtained to date and the future use of herbicides 

as a roadside maintenance tool appears to be assured. 

Following is a brief description of the work accomplished in 

1958 and a description of the recent experimental work. Costs inclUde 

materials, labor and eqUipment at established rental rates. 

Broadleaf 

Need Control 

Chemicals - Low volatile ester of 2, ~-D containing ~ Ibs. 

acid equivalent per gallon. 

Standard treatment - ! gal. 2, ~-D in a minimum of 50 gal. 

of water per acre applied at any time throughout the growing 

season to varying widths at right of way. 

~nount treated - 53~6 acres on l6~5 miles of highway. 

Average cost - ~~.OO per acre 

Results - At least one machine mowing eliminated and 

appearances improved. 

Observations - In general only one treatment at any time 

during the growing season was attempted. The results point 

out that one treatment a year will eliminate a large percentage 

of the weeds that are a mowing problem.

Chemical I'lowing of Guide Rail. Posts and Signs 

3rush 

481 

Chemicals - Radapon plus low volatile ester of 2, 4-D containing 

4 Ibs. ac~d equivalent per gallon. 

standard treatment - 30 Ibs. Radapon plus ~ gal. 2, 4-D in 

a minimum of 30 gal. of water per acre applied in the spring 

before growth reaches 9 inches in height~ A three foot wide 

strip was treated in the guide rail line as well as the area 

immediately surrounding individual posts and signs. 

Amount treated - 1768 miles of guide rail, posts and signs 

on 4956 miles of highway. 

Average cost - $20.50 per treated mile. 

Results - At least one and in some cases all, hand mowings 

were eliminated. 

Observations - The chemicals used did an excellent job of 

removing all vegetation growing at time of treatment but 

left the treated area open for mid-summer growth of annual 

weeds and grasses. This was especially noticeable this 

past summer. The growth of annual weeds and grasses as 

well as the regrowth of some perennial grasses such as 

orchard and quack grass was so strong that in many areas 

mowing was required by late summer. 

Control 

Foliage 

Treatment 

Chemicals - Low volatile esters of 2, 4-D and 2,4,5-T 

containing It Lbs , acid equivalent per gallon. 

Standard treatment - ~ gal. 2, 4-D and ~ gal. 2, 4, 5-T 

in 100 gal. of water applied at 100 to 200 gal. per acre. 

Amount treated 

- 337 acres. 

Average cost - $15.80 per acre. 

Results - Cannot be determined until 1959. 

Observations - This work generally limited to regrowth of 

cut brush or other brush growth where the height or location 

of the brush is such that leaf discoloration would 

not be considered objectionable.

Combination Foliage Treatment &Weed Control 

Chemicals - Same as for foliage treatment. 

Standard Treatment - Varying amounts of 2, 4-D and 2,4,5-T 

with total of about 2 Ibs. acid in a minimum of 50 gal. of 

water per acre. 

Amounts treated - 308 acres 

Average cost - $6.15 per acre 

Results - Good weed control and defoliation of brush. 

Observations - This type of treatment apparently holds brush 

in check with a minimum of brown-out with the possibility of 

a yearly treatment eliminating all but the resistant species. 

Stump and Stubble 

Treatment 

Chemicals - Same as for foliage treatment. 

Standard treatment - 2 gal. 2, 4-D and 2 gal. 2, 4, 5-T in 

a minimum of 50 gal. of oil per acre. 

Amounts treated - 19 acres. 

Average cost - $104.00 per acre. 

Results - Cannot be determined until 1959. 

Observations - The accepted method of treatment with hand 

guns is costly in time and labor and often difficult on 

the cut and fill slopes found on the roadsides. 

Poison 

Chemicals 

Ivy ~ontrol 

- Amino Triazole 

Standard treatment - 4 lbs. Amino Triazole in 100 gal. of 

water applied at approximately 100 gals. of water per acre. 

Amounts treated - Spot treatment on 2200 miles of highway. 

Average Cost - $20 to $25 per acre in Babylon District. 

Results - Excellent top kill but final results cannot be 

determined until 1959. Results of 1957 wor-k in one district 

indicate 99% kill.

Chemical howing in GUide Rail 

Material 

Tel var 

Tel var 

"WI 

11DVlII 

Simazine 5011 

Simazine 

.l'elvar 

Telvar 

Simazine 

5ml 

"DiN" 

ImI" 

50VI 

Simazine 50\1 

Simazine 

Simazine 

5mv 

5mJ 

Simazine 50\1 

Baron 

+ 2, 4-D 

Telvar II"YI" 

+ Radapon 

+ 2, 4-D 

Telvar 

+ Radapon 

+ 2, 4-D 

"VI" 

Simazine 50W 

+ Radapon 

+ 2, 4-D 

Experimental 

District 

A. Hornell 

Work 

40 l~s./A. Hornell 4/53 

40 Ibs./A Bab~~~a 4/58 

40 Ibs./A Hornell 5158 

30 Ibs./A Babylon 4/58 


22.5 Ibs./A Babylon 4/58 

20 Ibs./A Hornell 4/58 

20 Ibs./A Utica 4/58 


10 Ibs.1 A Hornell h/58 

5 gal./A Hornell 4/58 

2 Ibs.acid/A 

5 Ibs./A Hornell 5/53 

30 Ibs./A 

2 Ibs.ac:id/A 


30 Ibs./A 

2 Ibs. acidl A 

5 Ibs./A Hornell 

30 Ibs./A 

2 Ibs.acid/A 

Date 

of 

Ratin 

9 

483 

9/58 Satisfactory 








9/58 Unsatisfactory 





5/58 9/58 Satisfactory 

Simazine 50W 5 Ibs./A Babylon 4/58 9/58 Unsatisfactory 

+ Radapon 30 Ibs./A 

+ 2 4-D 2 Ibs.acid/A 

---~-------------------------------------------------- - - - - - - - - - - - - 

* Satisfactory - Sufficient vegetative control to require no 

mowing for one season. 

Unsatisfactory- Vegetative growth requiring mowing.

484 

BroQuleaf Jeed Control 

Low volatile ester of 2, 4-D at the rate of 2 Ibs. acid in 

both 30 gal. water per acre and 50 gal. water per acre was applied 

on 10 miles of highway in Hornell District in August, 1958. 

the 30 gal. rate was slower acting but final results were rated 

as e~ual to the 50 gal. rate. Rainfall was unusually high throu~hout 

the summer of 1958. 

Brush 

Control 

Karmex F. P. (Fenuron) 

Applied as a foliage spray on t acre of brush in late September, 

1958 in Hornell District. Leaf discoloration began 

to show at the same time as fall color. Results cannot be 

determined until 1959. 

Pellatized Karmex F. P. applied by sand blast gun on May 

'6, 1958 to a test area in Babylon District containing a 

moderately heavy stand of pine, oak, cherry and sassafras. 

One test plot treated at the rate of about 50 Ibs. per 

acre and a second test plot at about 25 Ibs. per acre. 

Excellent top kill was observed on both plots in September, 

1953. Grass and woody ground cover injured much more severly 

by the higher rates. Final results cannot be determined 

until 1959. 

Applied in Hornell District as a foliage spray in July,1958 

to evaluate delayed brown-out action as compared with the 

standard low volatile esters. No difference in reaction 

time was observed. 

Applied in Babylon District as a foli~ge spray for the same 

purpose as stated above. No differ~nce in reaction time 

was observed. 

Ammate 

A test plot in the Eabylon District was foliage sprayed in 

June, 1957 with 60 Ibs. of Ammate X with 4 oz. of Dufont 

Spreader-Sticker in 100 gal. of water. A second test plot 

was treated with 40 Ibs. of AffimateX with 40 gal. of No.2 

fuel oil and 2/3 pint of emulsifier in 96 gal. of water. 

Results were jUdged as satisfactory in September, 1958. 

Cherry and sassafrass were completely killed. Some regrowth 

of oak and resprouting of sumac and locust was observed.

485 

Amino Tria?ole 

Applied as a foliage .spray on 100 acres ofpredominarit oak 

vegetation in Babylon District. Treated in. June and July, 

1957 at a rate of 8 Lbs . in 100 gal. of water to brush 3.. 

feet high or smaller. About 90% kill was obtained. '. 

A mixture of 8 Lbs, Amino Triazole, ~ gal. 2, 4-D and f 

gal. 2, 4, 5-T in 100 gal. of water was sprayed on a small 

test area in Babylon District in July, 1957. About 80% . 

kill of all species, (pine, oak, cherry, locust and 

sassafras) was obtained.

486 

Experuunet.af use of Herbicides for reducing Road 11aintenance Costs 

on NewJersey State Highways 

Robert S. Green, N. J. State Highway Department 

The New Jersey State Highway Department began exper-Iraerrta.I use of 

heruicides in the spring of 1956 when the Department contracted for a trial 

weed control spraying program on 26 miles of the dualized U.S. Route I, from 

Trenton thru New Brunswick to the Garden State Parkway overpass. The contract 

called for three applications each year over a three year period , spraying 

with 2, 4-0 and 2, 4, 5T along each roadside and on the 12 foot grass median. 

In 1957 an additional 35 miles were added on U.S. 130 fram the 

Hi!;htstown By-pass to .iilltown Circle on U.S. 1 and on Rt. 23 fram Stockholm 

to Colesville. These locations were selected in order to show contrast with 

non treated adjacent roads and where little roadside maintenance occurred. 

In the spring of 1958, 96 miles of addittonal State Highway routes 

were added, coverin[ other parts of the State. At this time, with the third 

year of our first contract on the 26 mile stretch being reached, we were able 

to determine the advisability of continuing the project. 

The use of herbicides showed partial control of annual and broad leaf 

weeds the .Lirst year in many locations. Noticeable improveuent in turf growth 

followed and adjacent unsprayed private lands showed marked contrast even after 

the second year. 

On account of the varying weather conditions during the same season 

from year to Ybar it was difficult to determine the numberof mowings saved 

out we ~,elieve that an addition to the better stand of grass, pr9ctically free 

of weeds, we could count on a saving of two uowings per season. However, a 

definite and highly pleasing result was shown on the side areas, where little 

.aadrrt.enance is done by hand methods, this due mainly on account of the call 

for more Lmpor-t.ant..lB.intenance construction jobs. Here, weeds were disappearing 

and a lush growth of grasses, which, i1 only cut once a year, would present 

!;ood roadside appearance. 

Since we r.1B.intain excellent lawn areas on median strips,multple intersections, 

traffic circles and roadside improvelilent areas, we feel that weed 

control spraying can produce better results if applied to the lesser mowed 

roadsides and diff'icul t to r:lB.intain guard rail locations. 

In our past contracts of a trial and exper:Lnental nature only, we 

have been charged':~ 50.00 per mile for the three applications per year for 

both sides of a hi[hway,dual roads require one or two extra runs depending on 

the width of the median thereby increasing the cost to $ 75.00 or $100.00 per 

mle. 

The use of 2, 4-0 and 2, 4-5-T, must be used so as not to damage 

!;rasses uut, shall control noxious growth, inclUding the uore commonOnadelion, 

plantain and ragweed, and the more difficult to eliminate Poison Ivy, poison 

oak and wild cherry.

487 

8liiety of' application try "leans of low pressure with heavy droplet 

will deteat drift ot' material to areas beyond states rie'ht of way. Safety 

to vor-kLng per-sonne.l , to the ",lOtorist and to the pedestrian ,.lUi1tbe consdde ced 

at all ti!nes during each application, even tho the materials as ~ixed are 

non-toxic to h~nan and animal life and non-injurious to any of the several 

ues rr-eanl e specd.ea of grasses gi'owing on the roadsides. 

NewJersey has done very little in the use of chemical spraying 

auout guard rails and sign posts. In 1957 and 1958 a single application was 

uade on 18 .ailes of £uard rail areas bordering the roadsides on Route 23 in 

Sussex County. The object to derermine the effectiveness of various types of 

chemicals such as At1acide, Chlorea, Dalapon, Radipon and Siroazin. These were 

applied at various rates per acre. Up to this titie we have not deterDined 

which was superior. Further studies will be LIBdealong these lines during 

1959. 

The 1958 test applications applied in Aueust have shown varying 

degrees of el'l'e.::tiveness, but have had lit .Le time to deterilline if any particular 

herbicide is belter than another. Nor have we been able to figure costs. We 

do know that all types used did same good in weed elimination. Also that complete 

eradication of weeds and grass would in same instances cause runoff and thus result 

in serious erosion problems. 

Our latest test on guard rail treatment was conducted on 15 miles of 

roadside between Somerville and Belle :iead, application being .lade on 16,000 

lineal feet of rail for a width of 2 feet. Radapon was used in a mixture of 

2, 4-D and 2,4,5-T and water. The 400 gallon ;,lixture turned out to be sufficient 

for the 16,000 feet on the 2 foot width at an estL~ted cost of one and one half 

cents per squJre foot. 

WI.ile late Spet.eracer' was not the best til.'lElto treat the area which 

had not been mowedthis year, results were relnarkably good and gave reason to 

uelieve a late spring treatment would eliminate mowing or only require one 

.nowing thus inaking the guard rails cleaner and the roadside more attractive. 

Still another experiment was conducted on a ten Llile length of l!IEldian 

on U.S. Route 1 from Trenton to Princeton. An apj.LLcatd.on of Dolge 8.S. Weed 

Ai1ler was sprayed at the joint between the pavement and the concrete curbing 

bordering the grass reedian at the rate of 40 to one. Unsightly weed growth has 

always been abundant and hand tlethods of removal consumed much time and at Lar-ge 

costs. A short time later a stiff bustle mechanized broom renoved all t.race of 

dead weeds. This was a landscape maintenance operation which we hope to expand 

on during 1959. This will be in conjunction with the use of an application of 

20 to one Dolge on Poison Ivy areas adjacent to homes and schools and pedestrian 

traffic. 

In conclusion we believe it is only a matter of time before most states 

will be compelled to adopt a major program of weed control by spraying. The everincreasing 

road mileage of each individual State will demand maintenance expenditures 

far beyond reasonable Budgets. This has already been ap}roached in our 

state.

Adoption of a statewide weed control progr~l, let out under contract, 

to eliminate unsightly Erowth about ,=u,ordrails, sitnposts and intersections, 

will release hithway personnel for uore important road maintenance, reduce 

mowing costs and the need of additional landscape forces each year. Wewill 

have well kept roadsides throuout the state equal in appearance to our more 

important arteries which now receive a greater amount of landscape maintenance. 

New Jersey State Highway Commissioner Dwitht R. G. Pal~r in his 

1959 - 1960 uudget requests, seeks additional moneys to conduct more extensive 

weed and crush control spraying. We then will be able, durinf 1959, to extend 

our pro~rarfi in this field.

WEEDINGOF SWEETCORNWITHCHEMICALHERBICIDES l• 

CHARLESJ. 

NOLL 2 • 

Thirty thousand acres of sweet corn aze grown each year in Pennsylvania. 

Chemical weeding practices have been used over a good part of that acreage. 

TIlis experiment was designed to determine the best herbicides available, and is 

a continuation of investigations started a number of years ago. 

PROCEDURE 

The variety Iochief sweet corn was seeded June 3, 1958. Pre-emergence 

application of herbicides were made June 5, emergence treatments June 12, and 

the post-emergence treatment June 30 at the time the corn bad 4-5 true leaves. 

Individual plots were 70 feet long and 3 feet wide. Treatments were randomized 

in each of 6 blocks. 

The chemicals were applied with a small sprayer over the row for a width 

of 12 inches. The growing season was favorable with rain well distributed and 

averaging 1/2 inch a month in excess of normal. An estimate of weed control was 

made prior to harvest on a basis of 1 to ~O, 1 being most desirable and 10 being 

least desirable. Corn was harvested September 10tb and 11. 

RESULTS 

The results are presented in table I. All chemicals gave significantly 

increased weed control as compared to the untreated check. The best weed control 

was obtained with S:lnazin at 2 and 3 Ibs , per acre, Emid at 3 lbs. per acre 

applied in a pre-emergence application, G27901at 4 and 8 Ibs. per acre, Diuron 

at 3 1bs. per acre and Emid at 1/2 lb. per acre applied at time of corn emergence. 

Corn stand was significantly reduced as compared to the untreated check by 

Emid at 3 lbs. per acre applied in a pre-emergence application, ManuroDat 3 lbs. 

per acre and Diuron at 3 lbs. per acre. 

The number of marketable ears was reduced as compared to the untreated check 

by Emid at 3 lbs. per acre applied in a pre-emergence application, by Manuron at 

1 1/2 and 3 lbs. per acre, by Diuron at 3 lbs. pe. acre. and by Neburon at 3 lbe. 

per acre. 

The weight of ~arketable ears was reduced as compared to the untreated check 

by Emid at 1 1/2 and 3 lbs. applied pre-emergence, by Manuron at both 1 1/2 lbe. 

and 3 lbs. per acre, by Diuron at 3 lbs. per acre and by Neburon at 4 1/2 lbs. 

per acre. 

There was no significant difference amongtreatments in average ear weight 

but the following treatments reduced the number of ears per plant as compared 

to the untreated check plot: Emid at 3 lbs. in the pre-emergence application, 

Manuron at 3 lbs. per acre and Neburon at 3 lbs. per acre. 

1. 

2. 

Authorized for publication on Nov. 19. 1958 as Paper No. 2318 in the Journal 

Series of the Pennsylvania Agricultural Expertment Station. 

Assistant Professor of Olericulture. Department of Horticulture, College of 

A2l'iculture And Exnl!!lrimAnl" Stolltoi"n_ .,..... 'P.. nn" .. h ... n4 .. !I ........ IIn4 ........ 4 ....

4'-}O 

CONCLUSION 

No chemical treatment resulted in an increase in yield as compared.to the 

untreated check where sane weeds were 3 feet tall at time of hatvest. Undet'":more 

normal 'weather conditions where water was not well distributed or nearer normal 

for the growing season it is possible that a number of herbicidal treatments 

would have resulted in increased yields. 

The best treatments taking into consideration weed control, corn stand, and 

number and weight of marketable ears were Simazin at 2 and 3 lbs. per acre, 

G2790l at4 aDd 0 lbs. per acre and Benzac at 3 lbs. per acre.

( 

( 

I. Weed control, plant stam, number and weight of ears, average ear weight and number of ears per plant of 

sweet corn under chemical herbicide treatments. 

AVERAGEPERPLOT 

Rate per Wben ""Need Corn Marketable Ears Average No. ears 

~ Acre Applied Control ~ ~ . Weight Ear Weight per Plant 

lbs. Ibs. 1bs. 

lD8 -- .- 9.50 97.0 93.2 53.1 .58 .97 

lin 2 Ibs. Pre-emergence 1.17 97.3 .. 93.2 58.1 .63 .96 

3 Ibs. " 1.00 93.3 88.7 55.3 .62 .96 

1 1/2 lbs. 

ft 

2.33 92.3 82.7 48.4 .59 .90 

3 Ibs. " 1.33 13,3 47.0 26.0 .57 .64 

11 4 lbe. 

ft 

1.17 91.7 90.3 56.5 .63 1.00 

8 Ibe. 

ft 

1.33 98.0 8g e5 55.5 .62 .92 

'azin 6 lbs, 

ft 

2.33 97.2 88.3 54.5 .62 .91 

I·. 12lbs. 

ft 

1.67 99.8 92.5 56.8 .62 .93 

lex 6 Ibe. 

ft 

3.33 98.3 93.0 58.1 .63 .95 

9 lbe. 

ft 

2.83 97.3 90.3 57.5 .64 .93 

:cl0JA 1 1/2 lbs. 

ft 

2.00 98.2 88.7 58.6 .66 .91 

" 

3 lbs. 

ft 

1.33 96.7 96.5 56.5 .59 1.00 

on 1 1/2 lbs. 

ft 

1.33 90.0 78.8 45.4 .58 .87 

3 1bs. 

" 

1.00 60.8 42.8 24.4 .59 •• 64 

n 1 1/2 Ibs. " 2.00 93.7 37.8 54.4' .62 .94 

3 Ihe. " 1.17 86.7 13.5 44.3 .60 .135 

1/2 lb. Emergence 1.50 101.5 92.5 58.1 .63 .92 

3/4 lb. " 2.33 97.0 92.2 57.0 .62 .95 

Amine 1/2 lb. 

" 

2.50 97.0 87.9 57.1 .65 .91 

;-" 3/4 lb. " 2.00 97.5 86.3 52.2 .60 .90 

r8~ " 2 Ibs. 

" 

1.67 92.2 83.0 51.1 .62 _. 

.90 

oJ s:1hs. 

ft 

1.67 95.3 32.3: . 51.5 ~ 62 .87 

Dn 3 Ihs. 4-5 true leaves 3.67 ~3.3 77'.7·. 50.0 .64 .84 

4 1/2 Ibs. 

" 

2.50 92.7' 86.1"- 49.3 .57 .94 

Significant Difference (P;:; .05) .55 10.3 13.5 ~.7 ..;. -. " NSD .13 

ft ft 

(P: ,01) •.75 14.0 18.3 . 11.8 .. ~ ,:: NSD .18 

,. 

Control 1-10 

l Perfect Weed Control 

I Full Weed Growth 

.: -:0- f:- 

-r :" 'C ......

492 

Over 5000 acres of lima beans are grown annually in Pent)Sy1vania. Much of 

this acreage could b>3w~8d.ed with presently. recoUaellded 'herl:lic'ides~ Each year 

new. and poasib1y bectft.' blIrbicides are !lvailab1e. This investigation was 

designed to further test Dewer chemicals now available l'gainst chemicals DOW 

recommended. This is a continuation of an investigation started a number of 

years ago. 

PROCEDURE, 

Seeds of the 11.. bean variety Fordhook 242 were planted June 3. 1958. 

Herbicides were app11ed JUDe 6 prior to the emergence of the beans. IDc1ividua1 

plots were 20 feet long by 3 feet wide. Treatments were randomized in:each of 

10 blocks. 

The c~icab were applied ~ith a small :sprayerClV~. the row for a width 

of 12 inche,s. The growing senOll'was good with sufficient rainfall well 

distributed 'over the growing season. An estimate of weed control was made prior 

to harvest on a basis of 1 to 10. 1 being most desirable and 10 being least 

desirable. The plants were pulled and marketable beans harvested September 25. 1958. 

REStlLTS 

The results :~e presented ~n table I. All chemicals gave a significantly 

increased weed control as compared to the untreated check. The stand of plants 

was reduced as compared to the untreated check with Niagara 5521 at2 1/4 sal. 

per acre. ACPMl18 at 3 and 4 1/2 1bs. per acre and ACPMl19 at 3 1bs. per acre. 

Yields were significantly increased as compared to the untreated cheCk with 

Dinitro at 4 and 6 Ibs. per acre, Ch10razin at 4 and .6 1bs. ,p!!r .acre, ACP 

Ml19 at 3 Ib".per acre, Nehuron at '6 'and 9 1bs.per acre and 027901 at 4 1bs. 

per acre. There was no significant difference between these better treatments 

in regards to yield of beans in the pods. 

SUMMARY 

Amongthe best of the treatments was Dinitro. the material now recommended 

for the weeding of this crop. Other chemicals that look prOlllising and are 

worthy of furth.r iaVestigation are Chlorezin and Neburon. 

1. 

2. 

Authorization for publication Nov.' 19. 1958 as Paper No. 2316 in the Journal 

Series of The Pennsylvania Agricultural Experiment Station. 

Assistant Professor of 01ericu1ture. Department of Horticulture. College of 

Agriculture and Experiment Station. The Pennsylvania State University. 

university Park. Fennsylvania. --

493 

Table I. Weedcontrol. stand of plants, and weight of lima beans in pods 

under chemical herbicide treatments. 

Herbicide Rate per Acre *WeedControl Stand of Plants Wt. Beans in Pod 

Ibs. 

1bs. 

Nothing 7.7 ~4.0 7.4 

Dinltro 4 3.5 24.4 10.7 

" 6 2.3 22.5 10.5 

Chloro IPC 6 4.4 19.0 8~7 

" " 9 3.5 18.6 9.3 

Chlorazln 4 3.3 21.7 10.1 

" 

6' 3.1 25.1 10.4 

Niagara 5521 2 1/4 gal. 5.3 17.1 7.2 

II 

" 

3 3/8 gal. 3.4 19.6 9.5 

ACPans 3 2.1 14.1 8.9 

II 4 1/2 2.4 13.3 8.1 

" 

ACPMU9 2 3.0 21.3 9.4 

fl." , 

" 3 1,9 18,1 10.1 

Neburon 6 2.7 22.1 U.S 

" 9 2.1 25.4 12.0 

G-27901 4 1.8 19.9 9.9 

" 0 1.3 18.8 8.3 

" 

12 1.2 20.9 8.8 

Least Significant D1fference(P:.05) 1.5 5.5 2.4 

" " " (11:.01) 2.0 7.3 3.2 

·weed Control lal0 


10 Full WeedGrowth

4% 

A NOTEOF THE CONTROLOF NO'iTHERNNUTGRASSIN SNAP BEANS 

M.F. Trevett 

and Edward Austin!! 

Ethyl di-n-propylthiolcarbamata (EPTC) applied preplanting in 

1957 at the rate of four and six pounds active ingredient per acre 

did not result in satisfactory control of northern nutgrass, 

(Cyperus esculentus L.). Records of nutgrass emergence indicated 

that the low order of control""obtained was the consequence of a 

comparatively long incubation period of the herbicide before nut 

grass sprouted. It appeared a reasonable assumption, therefore, 

that percent nutgrass control could be increased if application of 

EPTC was deferred until nutlets had sprouted and were making active 

growth. Such a practice would insura a high concentration of herbi- 

,cide in the sol1 during" a period of active absorption. 

Procedure 

A field with a soil of sandy loam texture, that had been plowed 

in October, 1957 was disk harrowed to a depth of four inches July 8, 

1958. At the time of ':disking, nutgrass was three to six inches tall. 

Soil moisture was eig~ty percent of field capacity. 

EPTC, applied ina randomized block, at the rate of six pounds 

active ingredient per acre ';"," was immediately disked in. Snap 

beans, variety Long T~ndergreeen. were planted July 9, 1958. 

All plots were rototilled five times during the grOWing season. 

Treatments are given in Table 1. Beans were harvested Septemb&r 9. 

Results 

l~eed control ratings and bean yields are given in Table 1. 

Nutgrass control.averaged 94.7 ~ercent nine weeks after application 

of six pounds per acre of EPTC. EPTC did not control 

Brassica nigra. 

Yield of EPTC pl;ts that were hand-hoed twice was significantly 

higher at the five percent level than plots that were hoed but not 

treated with EPTC, but. did not differ- sign1ficantiy rrom EPTC plots 

that were either hoed or hoed only once. 

I' 

1 Associate Agronomist and Technical Assistant, Department or 

Agronomy, University of Maine.

Conclusions 

Control of northern nutgrass in snap beans. with 8PTC can be 

increased if preplanting treatments are deferred until nutgrass 

has sprouted and is making active gr-ovt.h , EPTC should be worked 

into the soil following prior harl'owing of the sprouted nutlets. 

495 

Pre-emergence application of other herbicides may be required 

for comnlete weed control, particularly if gpecies of Brass1ca are 

present. 

Table 1. Yield of snap beans and percent broadleaf weeds and 

northern nutgrass control following application of 

6 pOunds EPTC per acre. 

Treatment]) 

EPTC, hoed 22 July + 4 Aug. 

~PTC, hoed 4 August 

SPTC, hoed 22 July 

EPTC only 

Hoed only 22 July + 4 Aug. 

Hoed only 22 July 

Hoed only 4 August 

Check 

Yield 

Pounds Snap 

Beans 

Per Acre 

Percent Weed Control 

9 Sept. '58 

Nutgrass Broadleaf weeds£! 

6747 95 93 

6457 95 83 

6187 97 60 

5046 92 30 

4253 10 83 

3944 0 0 

3731 5 33 

1624 0 0 

L.S .D. 5/; 

2477 

]) All plots were rototilled five times during season. 

EPTC was applied at 6 pound active ingredient per acre. 

~I Principal broadlesf was Brassica nigra L.

496 

CONTROLOF ANNUALWEEDSIN SWE7TCORN111/ITHMIXTURBSOF DNBP, AND 

DIURON, SIMAZIN, ORATRAZINE 

M.F. Trevett and Edward Austin!! 

Introduotion 

This paper is a report of a comparison of the effectiveness of 

mixtures of certain herbicides on the control of annual broadleaf 

weeds and annual grasses in sweet corn. The herbicides used were: 

4,6-dinitro ortho secondary butylphenol (D~BP); 3(3,4-dichlorophenyl)-l,l-dimethylurea 

(Diuron); 2-chloro-4,6-biS-(ethylamino)-striazine 

(Simazin); and 2-ohloro-4 ethylamino-6-isopropylamino-striazine 

(Atrazinb). 

Procedure 

Variety Marcross 13.6 sweet corn was planted June 9, 1958, one 

to two inches deep in a sandy loam soil. Treatments were replicated 

seven times in a randomized block in which single-row treated plots 

were ryaired with untreated nlots. Herbicides were applied with one 

pass of a small plot sprayer, at 40 pounds nressure and 50 gallons 

per acre volume. All nlots were cultivated throughout the season, 

but during cultivation the soil was not disturbed six inches on 

either side of the crop row. Corn was harvested at the soft dough 

stage of maturity. 

Planting (PL) apnlications were made June 9, emergence (EM) 

apolications were made June 17. Counts of annual grass were made 

August 21 (8.5 weeks after planting), counts of annual broadleaf 

weeds were made August 4 (seven weeks after planting). 

The principal broadleaf weeds were Black mustard (Brassica 

nig~~ Koch.), Red-root pigweed (Amaranthu~ retroflexus L.), 

and Lambs-quarters (Chenopodi\~ ~ L.). The annual grasses 

present were Barnyard grass {Echinochloa crusgalli Beauv , ),and 

Foxtail (Setaria viridis L., Beauv.). 

Rain fall data are found in Table 1. 

Results 

Yields of snapped ears are found in Table 2, percent broadleaf 

weed control in Table 3, and percent annual grass control in 

Table 4. 

1 Associate Agronomist and Technical Assistant, respectively, 

Denartment of Agronomy, University of Maine.

497 

On the basis of Duncan's Multiple Range Test, a mixture of ,);5 

pounds of Atrazine and 3 ?~unds of DNBP, apolied at emergence (Treatment 

No.1, Table 2), was the only treatment giving significantly 

higher yields than the: s sandar-d treatment of 4.5 pounds of DNBP 

apnl1ed at emergence (Treatment No. 12, Table 2). The only treatment 

resulting in significantly lower yields than standard was1.2 

pounds Diuron applied at planting (Treatment No. 17, Table 2). 

Treatments resulting in higher "P9rcent control of both annual 

broadleaf weeds and annual grasses are conveniently presented as 

follows: 

TREATMPNTS.~ESULTING IN SIGNIFICANTLYHIGh~R WE~~ dON~ROL THAN4.5# 

. DNBPAP"LIED AT EMERGENCEY. . 

Annual Broadleaf Weeds 

Nf'.2 GJ1.0# Simazin E~. 4.5# DNBPEM.i/ 

" 9 2.0# Atrazine PLSr 

" :) 0.8# Diuron EM + 4.5# DNBPEM 

" 8 0.8# Diuron EM + 3.e# DNBPEM 

"3 Hand hoed only 

It 1 0.5# Atrazine EM + 3.0# DNBPEM 

It 7 0.5# Atrazine EM+ 4.5# DNB'PEM 

"14 c.S# Simazin EM + 4.5# DNBPEM 

" 11 1.0# Simazin EM + 4.5# DNBPEM 

"10 0.4# Diuron· EM + 3.tJ# DNBPEM 

It b 0.4# Diuron EM+ 4.5# DNBPEM 

"16 2.0# Simazin 1'L 

"13 0.5# Simazin EM + 3.0# DNB'PEM 

It 17 

Annual 

Grasses 

1.0# SimRzin EM + 4.5# DNBPEM 

0.8# Diuron EM + 4.5#DNBF EM 

Hand hoed 

only 

Q.S# Simazin EM + 4.5# DNB1'EM 

0.4# Diuron EM + 3.0# DNBPEM 

C.4# Diuron EM + 4.3# DNBPEM 

1.2# Diuron 1'L 

11Duncan's Multiple Range Test. 

2/ No. refers to treatment number, Tables 2, 3, and 4. 

1/ EM = applied at emer-gence PI, = ap oLd.ed at planting. 

Treatments significantly lower than all others in broadleafweed 

control were.the standard emergence apDlication of h.S pound DNBP 

(Treatment 12, Table 3) and planting apulications·of 1 pound Atrazine 

('!'raatment 4, rrable 3), 1.2 pounds D~uron (Treatment 17, Tallle 3), 

and 1 pound Si~zin (Treatment 15, Table 3) •. Treatments that did 

not dif.fer significantly f:rf\ll1st.andard in annual grass control included 

planting applieS. thn~ ".f2 oounds Atrazine (~rea tment 9, Table 4), 

Z pounds Simaz,in '(Treatment16, Table 4),1 p/,\und Atrazine (Treatment 

4, Table 4), 1 poundSimazin (Treatment 15, Table 4) and the 81nel'geuoe 

apnlication of e:mixtl',re of 0.5 oounda Atrazine and .3 tJ"1)n(l~ DNB? 

(Treatment 1, Table 4).

49$ 

Although five chemical treatments gave signifioantly higher 

control of both annual broadleaf weeds and annual grasses than 4.5 

pounds DNBPa?plied at emergenoe, only one treatment resulted in 

significantly higher yields (Treatment 1). This anomaly can perhaps 

be explained by the assumption that the level of weed control 

obtained with 4.5 pounds of DNBPwas sufficiently high to permit 

near miximum yields for the magnitUde of weed population and environmental 

and cultural conditions prevailing. 

The yield depression following planting application of either 

1.2 pound Diuron or 2 pounds of Simazin (Treatments 16 and 17 

respectively, Table 2), appeared to be due to herbicide injury to 

the corn. 

One pound Atrazine and one pound of Simazin applied at nlanting 

are phytotoxically equal to 4.5 pounds of DNBPapplied at emergence. 

Conclusions 

Significantly better annual broadleaf weed and annual grass control 

than resulted from an apnlication of 4.5 pounds DNBPat 

emergence in sweet corn was obtained by emergence apnlications of 

the following mixtures: 1 pound Simazin and 4.5 pounds DNBP; 0.8 

pounds Diuron and 4.5 pounds DNBPj 0.5 pounds Simazin and 4.5 pounds 

DNBP; 0.4 pounds Diuron and 3.0 pounds DNBPi and 0.4 pounds Diuron 

and 4.5 pounds DNBP. Approximately the same relationship applies 

to planting apnlications of either one pound of Simazin or one 

pound of Atrazine, since these rates of Simazin and Atrazine are 

phytotoxically equivalent to emergence applications of 4.5 pounds 

DNB? Planting applications of 2 pounds of either Simazin or 

Atrazine resulted in significantly better annual broadleaf weed 

control than 4.5 pounds DNBP, but did not differ significantly from 

DNBPin annual grass control. 

Mixtures of herbicides, or rates of individual herbicides, resulting 

in significantly better overall weed control than standard 

(4.5 pounds DNBP) should not be unrestrictedly suggested for general 

commercial use , since enhanced weed control may not be accompanied 

by either higher yi~lds per se, or by higher yields economically 

obtained. In the present test, although the standard treatment was 

excelled by five mixtures for total annual wged control, and by 

twelve treatments for annual broadleaf weed control alone, and by 

six treatments for annual grass control alone, only one treatment 

nroduced significantly higher yields than standard. Thus, while 

data such as obtained in the present test may be of limited usefulness 

they do indicate possible solutions to unusual and specifio 

annual weed problems.

499 

TABLE1. RAINFALLJUNE - JULY 1958. MONMOUTH, MAU'E 

Date Inches Date Inches 

June 1 .37 July 11 .05 

11 

" 2 .50 15 .43 

11 

11 

11 .05 18 .33 

" 20 .70 " 19 .02 

" 24 .01 " 21 .35 

" 25 .29 " 22 .01 

11 

30 .52 " ~ .12 

11 

25 .39 

July 2 .18 26 .35 

11 

.01 " 27 .35 

~ 

.01 28 .35 

" 7 .93 " 29 .45 

" 10 .66

) 

) 

'rABLl£2. EF~i'ECT OF rUXTURESOF DNBPvrra DIURuN, SIM,.'.ZINORA1'l'lA.ZlNEONYBLD OF SWEETC( 

Treatment!! 

Simazin Yield Tons 

HankY 

Diuron Dr Snapped Ears Yield Annua~/ Broadle1i7 

No, Atrazinu + DNBP Per Acre Gras Weeds 

1. 0.5# Atrazine EN + 3.0# DNBPEM 8.38i ~ 1 12 6 

2. 1. '")-iJ Simazin EI'i + 4.5# D1TBPEJIil 8.27 1-- 2 3 1 

3. Hand hoed only 8.24' ! 3 1 5 

13 14 

4. 1.0#~trazine PL 8.16 i I 

~ 

5. 0.8# Diuron E).'1+ 4.5# DNBPE.l'1 8.09 I L~ 13 

6. 0.4# Dim on EM + 4.5# DNBPEM 7.93 ; 6 2 11 

7. 0.5# Atrazine EI1 + 4.5# DNBP EM 7.92 i 7 15 7 

8. 0.8# Diurcn EM + 3.0# DNBPEH 7.82: I 8 8 4 

9. 2.0# Atrazine PL 7.56 I 9 9 2 

10. 0.4# Diuron EM + 3.0# DNBPEM 7.53 ! I 10 7 10 

11. 1.0# 3imazin EM + 3.0# DNBPEM 7.50 i I 11 10 9 

12. 4.5# DNBPEM 7.49 I I 12 16 17 

13. 0.5# Simazin EM + 3.0# DNBPEM 

7.30 i I 13 

It 13 

14. 0.5# Simazin EM + 4.5/1 DNBPEM 

7.'9~ 

14 8 

15. 1 .0# Simaz in PL 7.13----. 15 17 16 

16. 2. ()# Simazin PL 6.92 16 11 12 

17. s.z» Diuron PL 5.79 . 17 5 15 

, 

L.S.D. 5;; ----1.22 

1;6 1.48 

Y PL = herbicide appli~d at planting, 9 June '58. EM= herbicide applied at emergence, 

17 June '58. Herbicides given as pounds por aero of active ingredient. 

~/ 1 - r.ighest yi01d etc., 19 - lowest yield etc. 

~ 

Barnyard grass - Echinochloa crusgalli L. 

Amaranthus retroflexus L; Chenopodium album L. _ 

021 Means included within brackets are not significantly difforent at 5% lovel. 

e (Duncan's Multiple Range Test). 

~

( 

ThBLE 3. EF"ECT OF MIXTURES OF DNBP \VITH DIURON, SllLZIN, OR _.TR...ZINE ON .aHO"DLE. F 11!'EED 

CONTROL IN SWEI

) 

) 

I '.BLE 4. 

EFF£C'.I.'OF IlIXTURES OF DNBP\IITH DIURON, SIM:.ZIN OR A'l'Ril.ZINEONANAU1\LGRi,SS CON.i'ROL 

IN SWEETCORN. 

No • 

3. Hand hoed only 

11 

Treatment 

Diuron 

Simazin or 

"trazine + DNBP 

6. O.4J D~uron EM + 4.5#DNBP EM 


5. 0.8# Diuron EM + 4.5# DNBPEM 

17. 1.2# Diuron PL 


10. 0.4ff Diuron EM + 3.0# DNBPEM 

8. 0.8# Diuron EM + 3.0# DNBPEM 

9. 2.0# Ltrazine PL 

11. 1.0# Simazin EM+ 3.0# DNBPEM 

16. 2.0# Simazin PL 

1. 0.5# Ltrazine EM + 3.0# DNBPEM 

4. 1.0# ~trazine PL 

13. 0.5# Simazin EM+ 3.0# DNBPEM 

7. 0.5~1 C\i"lazin EM + 3.0# DNBPEM 

12. 4.5# DNBPEM 

15. 1.0# Si~azin PL 

.mnua L Grass Control RiinkJ7 

21 ~ugust '58~ C.rass Yield Broa~ 

Percent longles Control 1 eaf' 


'ontre 

100.Ji. 

99.5 1-, 

9~.5 l L... 

97.5 t : I 

9b 7 ' I • 

• I' I 

96. 3 ~ I L 

92.4 I •• ,I 

91.6 !: ~, 

_ I. j 

90.0 ' ,; 

85.9 ~ I . , 

85.7 I 

85.5 It,; 

85.0 " I 

79.6 -'.'J " 

77.2 .I " 

74.7 -r- 1 

74.6 I 

90.00 86.08 h , ' 

82.96 : ; 

80.82 ' "-; 

79.57 1 ! ~' 

78.98J I . 

73.97 I 

73.13 I Ii' 

71.51 iii I 

67.98 - I I i 

67.81 I I ! 

67.59 I I I 

67.25 

63.16 ---' 

JI 

: 

61.48 . 

59.78 

59.74___ 

'~ ---:- ~' -----,L,,-,-. 3~ IJ.:

503 

CON'l'ROLOF ANNUALWEEDSIN SNJ:.PBEA~TS WI1H j\IIIX'T'Ut:lES OF DNB?, CDEC 

OR EPTC 

M.F. Trevett and Edward Austin ll 

Introduction 

This paper is a report of a comparison of the effectiveness 

of mixtures or combinations of cu.rrently approved herbioides for 

snap beans with the same herbioides applied singly. The herbioides 

used were 4,6-dinitro ortho secondary butylphenol (DNBP);2-ohloro81lyl 

diethyldithiooarbamate (CDEC); and ethyl di-n-propyl 

thioloarbamate (EPTC). It appeared desirable to test oombinations 

of these, herbioides sinoe individually they do not oontrol both 

annual grasses and annual broadleaf weeds equally well. DNBP, 

for example, is considerably more effective on broadleaf weeds 

than on annual grasses. CDECand EPTC, on the other hand, are 

essentially graminioides. 

Procedure 

Snap beans, variety Long Tendergreen, were planted June 16, 

195~, one to two inohes deep in a sandy loam soil. Treatments were 

replioated fou~ times in a randomized blook. Eaoh treated plot 

was paired with an untreated plot. 

Only the inter-row area was cultivated throughout the season, 

the soil six in~hes on either side of the orou row was not disturbed. 

The urincipal broadleaf weeds were Chenouodium album L. 

and Amaranthus retroflexus L. The principal grass was EChIijOl2! 

crusgalli Beauv. 

Herbicides were apulied with a small plot sprayer at 40 pounds 

oressure and 50 gallons per acre volume. 

Rainfall data for June and July 1958 are found in Table 1. 

Weed counts were made August 19 (eight and one-half weeks 

after planting) for broadleaf weeds, and August 4 (seven weeks 

after planting) for annual grass. 

1 Associate Agronomist and Technical Assistant, respectively, 

Department of Agronomy, University of Maine.

504 

Beans were harvested August 19. 

The combinations of herbicides tested and acre rates of application 

of active ingredient are found in ~able 2. Various combinations 

of "at planting" (Pl) appl1cat.1ons with "emergence" (EM) 

apolications were compared. Comparisons of date of applioation 

aoeeared to be of potential consequence because DNBPhas been found 

most effective when apulied as weeds are emerging (generally 

coinciding with crop emergence), while CDECand EPTC generally , 

have been found most effective when apoLded prior to weed seed' 

germination. Early application of CDECand EFTC insures ample 

time for penetration to the depth at which weed seeds germinate. 

Thus, it was assumed that a oombination of 6~ of CDECapelied at 

olanting plus 4.5# DNBPapplied at emergence (Treatment No. 14, 

Table 4) would result in a higher percent annual grass control 

than if both 6# CDECand 4.5# DNBPwere applied at emergence (Treatment 

No.3, Table 4). 

Results 

Table 2 contains acre yields of snap beans, Table 3 percent 

control of annual broadleaf weeds, and Table 4 percent control 

of annual grasses. The rank assigned to treatments are identical 

in all tables. ' 

On the basis of Duncan's Multiple Range Test, 6# CDECapplied 

in combination with 3# DNBPat emergence (Treatment No. I, Table 2) 

~ave significantly higher yields than the following treatments.: 

4# CDECplus 4.5# D1~P applied at emergence (Treatment 15); 4# 

CDECplus 4.5# DNBPapplied at planting (Treatment 16); 4.5# DNBP 

applied at emergenoe (Treatment 17); 6# EPTC plus 4.5# DNBP 

applied at planting (Treatment 18); and 3# EPTC applied at planting 

(Treatment 19). Six pounds CDECplus 3¥ DNBPapolied at emergence 

(Treatment No.1), did not differ significantly in effeot on yields 

from the remaining treatments. 

The high degree of variation in this test precludes any preoise 

measure of treatment effect on bean yields. However, the distribution 

of ~reatment-rank for yield in Table 4 indicates a trend 

for low yields to be associated with either treatments giving low 

percent grass control or treatments giving the hi~hest oeroent 

grass control. Thus, treatments ranked 1, 2, 3 for annual grass 

control (Treatments No. 10, 18, 14, Table 4) are ranked 10, 18, 14 

resoectively for yield. Treatments ranked 16, 17, le, 19 for grass 

control are ranked 17, 12, 16, 19 respectively for yield. From 

these relationships it appears that six pounds of either CDECor 

EPTC apn Lfe d atolanting in combination with 4.5# DNBPaonl1ed 

either at olanting or emergenoe 1s associated with a trend towAt'ds '-./ 

low yields comp~red to emergence applications of CDECand EPTC in 

oombination with D1~P, Table 20

51'15 

Six pounds of EPTC apnlied at planting in combination with 4.5 

pounds DNBPapolied at either planting or emergence, and 6 pounds 

CDECanplied at planting plus 4.5 pounds DNBPapnlied at emergence 

(Treatments 10, 14, 18 resnectively) resulted in annual grass control 

significantly higher than for any of the other treatments. 

The following treatments resulted in s.:t,gnifioantly lower broadleaf 

weed oontrol than all other treatments:, 4# CDECat planting 

plus 4.5# DNBPat planting (Treatment 16), 6# EPTC at planting 

(Treatment 12), 6# CDECat planting (Treatment 4), 4# CDECat 

planting (Treatment 13), 4.5# DNBPat emergenoe (Treatment 17), 

and 3# EPTC at planting (Treatment 9). . 

Although 4.5# DNBPwas oonsiderably less effective in 1958 

than in previous years, 6# CDECapnlied pre-emergence either alone 

or in combination with either 3# or 4.5,¥ of DNBPfollowed the 

usual weed control pattern. The four year average (1955 to 1958 

inclusive) for pre-emergenee applications tollows: 

4.5# DNBP 

6.0# CDEC 

3.0if DNBPplus 6.0# CDEC 

4.5# DNBPplus 6.0# CDEC 

Conolusions , 

Peroent Weed Control 

BroadIea! Annual Grass 

72 

38 

~§ 

82 

71 

82 81 

Mixtures of DNBPand CDECor of DNBPand EPTC oontrol both 

annual broadleaf weeds and annual grasses more effectively than 

either DNBP, or CDEC, or EPTC annlied alone. 

Although the difference is not signifioant, there is a peroeptible 

trend for rylanting applications of either CDECor EPTC 

when followed by DNBPto reduce yields compared to mixtures of 

either CDECor EPTC and DNBPapplied at emergence. 

Disregarding the eoonomics of the situation, if in nrevious 

years DNBP. CDEC, or EPTC have not given satisfaotory overall weed 

control in snap beans, peroent control of both annual broadleaf' 

weeds and annual grasses can be increased by emergence applioations 

of either a mixture of 6# CDECand 3.0# or 4.5# of DNBPor a mixture 

of 6# or EPTC and 4.5# of DNBP.

506 

TABLF1. RAINFALLJUNE - JULy 1958. MONMOUTH, MAINE 

Date Inches 

-~ Inches 

June 1 .37 July 11 .05 

II 2 .50 15 .43 

11 .05 " 18 .33 

II 20 .70 19 .02 

II 24 .01 21 .35 

II 

" 25 .29 22 .01 

" 30 .52 " 24 .12 

" 25 .39 

JUly 2 .ie " 26 .35 

II .01 27 .35 

" i .01 " 28 .65 

II 7 .93 29 .45 

" 10 .66 

."",., 

"-/

( ( 

'I'ABLE2. :';~I G'

) ) 

Ti.BLE 3. EFF.2CT OF MIXTU11ES OF DNBPWITH EPTC OR CDECON BRO•.DI£..F WEED ,,;ONTROLIN SN._P .31 

No. 

1. 

3. 

9. 

10. 

2. 

14. 

18. 

3. 

6. 

7. 

5. 

II. 

15. 

16. 

12. 

4. 

13. 

17. 

19. 

Y 

Treatment 

EPTC or CbBC + -TINBP 

6i¥ CDECEI1 + 3. 0# DNBPEM 

6R CDECEM +4.5# DNBPEM 

3# EPTG PL + 4.5# DNBP PL 

611' ./!;l"l'C PL + 4.5# DNBPEr-r 

6# EPTC EM + 4.5# DNBPEM 

61¥ CDEC PL + 4.5# [,IffiP EM 

6# EFTC PL + 4.5# DNBP PL 

6# CDECPL 4.5# DrIBP PL 

4# CDEC PL + 4.5# DNBPEM 

6# CDECPL + 3.0# DNBP PL 

3# EPTC ~M + 4.5# DNBPEM 

6.0# DNBPEM 

4# CDECEM + 4.5# DNBPEM 

4# CDECPL + 4.5# DNBPPL 

6# EPTC PL 

6# CDECPL 

4·.',( 

r 

""~-r:'l(; 

Vb _.J PL 

4.5.1 DNBPEM 

3/ EPTC PL 

3roadleaf Weed ControlS! 

19 .•ugusf 1958 

Percent 

.mg.l es 

83.9-V 

73.7 '--.;. 

73.2 

71.8 

71.1 

70.0 

65.8 

63.0 ; h' 

62.6 ! 

61 4 I i I 

. "11 

57.5 ' ! I I 

50.0 I' Ii 

50.0-, . I : : 

34.9 .. : I ! I~ 

23.0--' . 

21.9--- 

1 . 

16.1 i . " 

12.9 ' 

5.7 

66036: 

59.14 : 

58.83 

h 

57.91 

56.79 57.47 f, 54.22 i 

52.56; I 

~~J~II .h 

Rankl! 

Broadleaf 

Control 

Yield Grass~ 

Contre 

1 

2 

3 

t 

6 

7 

89 

10 

11 

49.33 ! I' h 

45.00; 'h 12 

45 •00--l i : : 13 

36.22 iii. I 14 

28.62- I 'III 

I' 15 

27.72 

16 

23•64-_==--=--=-_=_---' I 17 

21.06 

18 

13. 83 ..__ ! 19 

1 

3 

9 

10 

2 

i~ 

86 

7 5 

11 

15 

16 

124 

13 

17 

19 

s 

4 

11 

1 

73 

2 

10 

8 

12 

14 

136 

18 

175 

15 

16 

19 

L,S.D. 5;(, 20.J~ 

Y PL = herbicide app Laed at planting - 16 June '58. EM= herbicide applied June 23, two 

d~ys before emergence. Herbicides given as pownds of active in:redient per acre. 

g; Principal broadleaf weeds were : l~aranthus retroflexus L; Chenopodium ~ L. Percent 

. was converted to angles for statistlcal analysis. 

'00 ~ Rank: 1 - hishest yield, grass control etic , , 19 - lo,.est yield etc. 

o Barnyard grlss: Echinochloa crusgalli L. . 

~21 Means incluced within bracke~8 are not significantly different at 5~ level (Duncanls 

MUltiple Range Test).

( 

( 

T;,BLE 4. 

EFFEJr OF lVJIJerURES OF DNBP \ofITH EPTC OR CDEC IN HNNU•..L GR.'.SS CONrROL IN SN:.P BEi.NS 

No. 

10. 

18. 

14. 

3. 

4. 

15. 

2. 

6. 

1. 

8. 

9. 

7. 

l1. 

.5. 

l3. 

L7. 

L2. 

1.6. 

.9. 

Treatment!! 

EPTc-or CDEC + DNBP 

6# EFTC PL + 4•.5# DNBP EM 

6# EPTC PL + 4•.5# DNBP PL 

6/1CDEC PL + 405# DNBP EM 

6J 0vECEM + 4.5# DNBP EM 

6# CDEC PL 

4# CDEC EM + 4.5# DNBP EM 

6# EPTC EM+4.5# DNBP EM 

4# CDEC PL + 4•.5# DNBP EM 

6# CDEC EM+ 3.0# DNBP EM 

6# CDEC PL + 4.5# DNBP PL 

3# EPTC PL + 4.5# DNBP PL 

6# CDEC PL + 3.0:# DNBP PL 

6. Ofl DNBP EM 

3# EPTC EM+ 4.5# DNBP EM 

4# CDEC PL 

4.5# DNBP EM 

6;¥ "'""TC PL 

4# c~~c PL + 4.5# DNBP PL 

3# EPTC PL 

.,n:lual Grass control Y 

4 :.ugust 1958 

Percent 

:.ngles 

:.nnual 

Grass 

Control 

91.3~7 

72.32-; 12 

89~5 ! 

71.14 I 3 

83.9 

7 0• 5o -L.. 4 

82.2 

6~.00 I 5 

82.0 

64.92 I 6 

80.1 

63.53 

78.2 

1 , 7 

62.18, 8 

77.8 

61.91 ' 9 

76.4 

60.92 

72.8 

1 

10 

58.60 I 11 

71.8 

57.91 h 12 

71.8 I 

;!h 

57.9 

67.0 0. 13 

l--, 

54.92 I ~ 14 

g~:~ 

4 6 • 0l ----J ! l-, 15 

28 7 

32.38 i ! 16 

I 

26:2 . ! 3 

13 •.5 ' I 

2• 38 1 17 

11.3 21.56 V.79 . I i 18 

19.62 

1~ 

-.,..--- 

L.~.V. ~~ 20.03 

Rank Y 

Yield 

10 

18 

14 

.3 

4 

15 

26 

1 

8 

9 

7 

11 

5 

13 

17 

12 

16 

19 

Broadlear 


Control 

/ PL = herbicide applied at planting - 10 June '58. EH = her-b.i c Lde ap vLied - 23 June '58, 

two days berore emergence. Herbicides given as pounds or actIve ingredient per acrc. 

I Barnyard grass: Echinochloa crusgalli L. 

/ Rank: 1 - highest yield, drass control etc., 19 -lowest yield, etic , 

I Means Lnc Luded within brackets art. not signiricantly dirrcrnnt at 5%level (Duncan 's 

Multiple Range Test). Percent was converted to angles ror statistical analysis. 

4 76 

2 

16 

I) 

.5 

918 

3 

10 

12 

11 

17 

18 

15 

14 

19 

VI 

Q 

-.:.

1/ Contribution from the Plant Physiology Department, Virginia Truck Experiment ~ 

Station, Norfolk. Paper No. 129. Journal Series. Approved for publication 

November 25, 1958. 

510 

PRE- ANDPOST-EMERGENCE WEEDCONTROL IN LEAFCROPS 

USING~!ERBICIDE COMBINATIONsl/ 

C. D. Price, Plant Physiologist 

Virginia Truck Experiment Station 

Norfolk 

Pre-emergence 

Trials 

Tbe two standard pre-emergence herbicides for leaf c~ops in Eastern 

Virginia are CDECand CIPC. Eech of the two herbicides has its advantages and 

disadvantages. CIPC is the cheaper of the two and is effective in controlling 

chickweed (St.tlaria media). CIPC cannot be used safely on mustard greens and 

it does not effectively control benbit (Lamiumamn1exicaule). CDECbas been 

found to be superior to CIPC in tbat it causes less crop stunting, can be used 

on a wider range of crops and will c~ntrol henbit (1). eDECis not as effective 

in controlling chickweed as CIPC. Both materials will control crabgrass 

(Digitaria sanguinalis). purslane (Portulaca oleracea) and goose8rass (Eleusine 

~). 

In recent researcb trials with leaf crops at the Virginia Truck Experiment 

Station, an effort has been made to combine some of the advantages of CDECand 

CIPC by using various combinations of the two herbicides. The results of two 

such pre-emergence experiments are reported here. C~ops included in trial No.1 

were mustard greens and turnip greens. Spinach was the test crop in trial No.2. 

Trial No.1: Pre-emergence herbicide sprays on mustard greens and turnip greens. 

Experimental information 

crop varieties: MUstard greens· Giant Southern Curled. 

Turnip greens - Pomeranian White Globe. 

Date planted: 8/27/57. Date treated: 8/28/57. Soil moisture: medium. 

Soil type: sandy clay loam. Exp. design: rand. block with 4 reps. 

Cultivation: none, pate of harvest: 11/8/57. Area harvested: 10 ft. of 

row from 3 rows each. Herbicide treatments: see Table 1. Spray per acre: 

25 gallons at 30 PSI. 

Bainfal1 record in inc~12r 1 wk. prior to and 3 wk. pe~iod follOWing 

treatments: 1 wk. prior~, 1st wk. after~, 2nd wk. after 1.77, 3rd 

wk. afte1'~, 4 wk. total 4.61. 

Temperature record f~r 3 wk. period follOWing treatmellts in degree hrs. above 

2.:l.: 1st wk. ll,lflj .• 2nd wk. 12,430, 31'd wk. 13,063, 3 w~. total 37.910.

~ 

( 

Table 1. Treatments and results of pre-emergence sprays on mustard and turnip gre~ls. 

Mustard Greens 

-Turnip Greens 

Lbs. per Plants per Lbs. per Lbs. per Plants per Lbs. per Weed 

Herbicide Rate/A. 30 ft. 30 ft. 100 Plants 30 ft. 30 ft. 100 Plants Control* 

CIPC 2 6.1 469 1.30 11.78 220 5.24 6.25 

CDSC 4 10.98 493 2.33 16.80 254 6.71 9.0 

CDEC 2 7.35 399 1.87 11.98 208 5.90 8.5 

CIPC 1/2 

CDEC 2 9.12 587 1.54 13.05 256 5.12 7.75 

CIPC 1/4 

CDEC 2 9.15 548 1. 75 11.92 190 6.44 7.50 

CIPC 1/8 

CDEC 1 9.92 536 1.94 14.62 237 6.32 5.0 

CIPC 1/2 

CDEC 1 10.52 503 2.17 13.78 215 6.52 6.25 

CIPC 1/4 

CDEC 1 10.58 527 2.02 14.38 242 6.17 5.50 

ClPe 1/8 

Check 0 9.18 609 1.54 13.38 242 5.54 2.0 

L.S.D. (51) N.S. 134 0.72 N.S. N.S. N.S. 1.76 

L.S.D. (11) N.S. 182 N.S. N.S. N.S. N.S. 2.38 

* l

512 

Results 

and Observation. 

Yield, stand and weed control results are shown in Table 1. CIPCat 2 

lbs. per acre measurably reduced the stand of mustard greens and gave some 

retardation of planta that did germinate. Turnip greens were retarded 

slightly and weed control was not satisfactory. COKCat 4 lbs. reduced 

GUetard green stand slightly but not significantly but did not retardarowth 

of plante. Turnip greens were not injured by the 4 lb. rate of COKCand weed 

control was very satisfactory. 

All combinations of COECat 2 lbs. plus 1/2, 1/4 and 1/8 lbs. of CIPC 

gave commercially acceptable weed control. The mustard green stand was 

greatly reduced with the 2 and 1/2 lb. combination but the resulting plants 

grew normally and resulted in only a slight yield reduction. The stand and 

yields of mustard or turnip were not affected by the 2 plus 1/4 lb. and 2 

plus 1/8 lb. combinations •. COECat 1 lb. in combination with CIPCat 1/2, 

1/4 and 1/8 Ibs. did not injure the crops but did not give satisfactory weed 

control. 

Trial No.2: Pre-emergence control of weeds in spinach ua1ng COEC,CIPCand 

EPTe herbicides. 

Experimental information 

Spinach variety: Old Dominion. Date planted: 9/17/57. 

Herbicide treatments: See Table 2. Dates treated: Treat. No.1 applied 

9/17/57 which was followed tmmediately by a 2.46 rain. Remaining treatments 

applied on 9/20/57 while soil was very moist. Spray per acre: 50 gallons 

at 30 PSI. ~1J' dedgn: Rand. block with 4 reps. Cultivation: none. ~ 

harvested: 1/3/58. Area harvested: One 3.5' bed, 30' long and 3 rows per 

bed per plot. 

Rainfall and temperature record: 

Period 'from 

Treatment 

1 wk. pl;ior 

1st wk. after 

2nd wk. after 

3rd wk. after 

Total 

Results 

and observations 

Inches ofaainfall 

.77 

2.46 

2.58 

2.62 

8.43 

2.46 

0.0 

3.08 

.L.!! 

7.66 

Temperature 

(Degree hIS. above 0·'.) 

Ireat. #1 treat •• #2-6 

12,374 

10,899 

12,046 

10,467 

~ 33,709 

~ 32,962 

COECat 2 Ibs./A. in combination with 1/4 Ib./A. CIPCapplied just prior 

to a 2.46 inch rain gave 1001 control of weeds for 5 weeks and was controlling 

commonchickweed 3\ month. later at harvest (Table 2). The spinach plants 

were noticeably .tunted after 5 weeks and had not completely grown out of it 

at harvest although yield. were not reduced significantly. The same traatment 

applied followins·the 2.46 rain as soon as field conditions permitted gave 

acceptable but .not complete weed control for 5 weeks and very little control 

of winte~.weeds. Sp~nach was not affected by this treatment. The combination

513 

:,~', , .. ' .... I) i 

of CDECat 2 lbs. with CIPCat 1/4 lb. gave comparable weed control results 

with 3 lbs. of CDECalone. 

EPTC at 8 lbs. gave a little better weed control for 5 weeks than did 

4 lbs. and neither rate reduced.spitlach, yields. However, these resultsiof 

no spinach damage do not agree withsome·later results at the Norfolk Station. 

where EPTC at 4 and 8 1bs. applied to a dry soil severely da~P'i;~the sp.inach. 

stand and growth. The combination of CDECand RPTC,,at·l JI) •.. each,·gave ·very 

satisfactory results in this experime~. ..!",. ··If. , .. , X '. ' 

-~- ':',! ··.i;~:· ··~'.:d::,·.~r·\ 

Table 2. Treatments and results for. ,pre ..emergencer;aptlay/f: on!.spi~)l.\·" 

l.~' l , ,. :!; . 

Treat. Chemical and ,; 

No. hulA in Lbs , 

1 CDEC..2 (Before 2.46" rain) 

CIPC·lj; 

2 CDRC"l (After 2.46" rain). .~... \ . 

EPTC·1 

3 EPTC·4 " 

4 EPTC·8 " 

5 CDEC·3 " 

6 CDEC·2** " 

CIPC·" 

7 Cheek 

L.S.D. 

's 

!' 

"-.' 

Av. Yield :in Lbs;,i" Weed Contrpl;1r 

per 30 ft, ... bed ,., 10/22/57 1/3/58 

10.75 

, 14.70 ., 

13.25 

12.68 

11.52 . ~.! 

14.25·\.1 

:.. ~y, 

',:'i j-" 

12.50 "" . 

N.S. 

.: 

'f 

l' 

10.0 

8.0. I. 

8.25" i' ;,/6.2~i 

9.0 ,r 

8.5. 

.: ,,'"1 

8.25 

,tI+.75 

·.t~;·,",,~ 

i; '._ :: ',~; . ,~r' ~,- 

r .' '~, " 

S~O/, 

8.75. 6.0."" 

5.5 

I" "': " 

.LO.. ' )" l.0 

* 1: no control, 10 = perfect control, 8 = conB1dered ac:c:eptabLt. '-;" 

** Treat. No. 6 altered from 1/8 lb. CIPC to 1/4 lb. CIPC-so ilii' "t'o'fcikpare 

treats. 1 and 6 on the basis of the effect of ralnfall,before4nd~af;,r 

treatment. 

* Weeds controlled: 10/22/57 - crabgrass, no control 

, b "-' -l 

ofpigweed,.except;.,lNo. 1 

1/3/58 • chickweed in treat'. No, 1, henbit 11Q( a Pllob~"m 

......;h· 

Summary and conclusions for pre· emergence trials 

\ '1;: '.,l 

1. CDECand CIPC were sprayed alone and in combinations ..as pn-emer.gence.' 

herbicides to mustard greens,turnip green. and sp.1aacb. ,Si':rCwas" included 

in the spinach trial. ,,''1 

2., Results indicate that combination sprays of CDEC.,,cIPC and EPTC:have very 

good possibilities for leaf crops. Rates of 2 ,lbs., CDRCin. ,combination .' 

with 1/4 to 1/8 lb. of CIPC were tolerated by mustard greens, turnip 

gr.ens and spinach with satisfactory early: weed control. The c~b~tion 

, of CDRCand, BPTCat 1 lb.:, eac~ ,looked promising on spinach".

514 

3. a••ulu .bowtbat rainfall either just prio~ to or ju.t after applying 

treat •• nt. can,reatly affect the results of pre-emergence treatments. 

Poat-emergence Trial. '"). 

With the aclventof .uccesaful pre-emergence weed control in leaf crop';I. 

the next obvloua need for leaf crop grower. i8 a herbicide tbat can be .afely\ 

lIaed aa a po.t· .... raence treat:1ll6nt. The residual from the pre-emeraence . " 

treatment nOl'lll8lly las loll from 3 to 6 weeks. Must leaf crops are then nOl'lll8lly 

at the thinning stage or large enough for a light cultivation where thinnln.·.·.l 

1a not practiced. Thi. would be the ideal stage of growth to apply an 

additional herbicide application for control of germinating weeds, flLeaf ",op' 

that are fall polanted and spring harvested ara in particular need of such /1(,\ 

treatlllent.A herbicidal application at late fall thinn1na that would keep die 

crop free of vinter ",eed. woul4 be most helpful. Spinach v... elected aa the 

test crop for testtns the pos.ibilities of auch a weed control prolf", 

Metbods and Material. 

',i,' 

Old Do1IIinioD.pinacb was planted in two location. on OCtober 16, 1957. 

Botb location. recetved • pre-amerlence herbicide of 2 lb •• per acre CDICin 

comblnation with 1/8 lb. per acre of CIPC. This treatment kept spinach we.d 

free for 5 week. witb no damage to tha spinach. On December 3, or "weeks 

afeer pre-emera_Dce treatmeDt., theeKperimenta1 post-emergence treatments were 

app11ed. Thi. was done i.-diately followlng a hand thinnlns and weeding in 

location No.1 •. In location No. 2 henb1t had besun to serminate and thi. wa. 

pulled by band witb no tb1nnins or cultivation. The aize of the .plnacb in 

each case wa. 2-3 1nche. in diameter witb 4-6 true leave.. aerbict4a1 treatmenta 

uaed and reault. for location No. 1 are shown in Table 3 and the .... i • 

•bOiWDfor location Mo. 2 in Table 4. Herbicides used included spreyand 

8ranular CDEC,CIPC and IPTC. Location No. I wa. band harva.ted on AprH 17, 

1958 and weed control retinaa .. de at that time. Location No.2 wa. band 

barvested on April 9. 1958 and weeds per 20 sq. ft. were puUed and ii.libed 

for each plot. \.1:' .,:, 

Bea u 1t •• 

nd pt'AAlfi9D. 

IfO heC'bic1de. _1tber .pray or sC'anu1ar, appUed poat- ... r.eace, to the 

.ptnach in eltbel'location .iplficantly affected the final spinach yielel. 

Bacb loeaUOD pC'ovtded a contl'a.t a. to the weael 'I'obl... In location 110. 1 

cbickweed wa. the _joC' pl'obl_ waed wbUa ln locaUOft 110. 2 hen"ie w•• tbe C), 

probl .. weed. '. . .... -... 

The beat treatllent in location lie. 1 wbera cbickweed wa. a pr.l .. ,waa a 

cOlllbinatiOil of COICat 1 11». ,er aore with C1l'C at 1/4 lb. per acre applied 

either a. a 'Pra, 01' in 'fanu1ar fona. eDKCat 2 11».. ..va .atiatactoC'y .. 4 

control to bane.t but elld Dot c..,letely contl'ol chickweed. UTC.at. ~ lb •• 

did not ,iv_ aa pod oOotl'ol a. tbe other tl' ntl wt dld not delMae 

the .pluch. .!be lar_l:ui.l with each tl' t wu .Uptly ~lol' 

ill weede_trol owelf CM c•• ubl_ .pray trut1lbl:, 

In loeation 110. 2 wlMie'blabit Wal the .. 1a 1*01»1... eel, tl'Uc.MtI 1 

aDd 3 contalni", 2 1".pu 8C1'8 ofCDIC .. ve very .ac~.,ace-' ..... CODuol

515 

; '.~ -:.t- • ' 

from time ?f application in December to harvest 1n'APril. Theaddition'of 

1/8 lb. CIPC to the 2,lbs. of CDECdid not appreci ..bly improve the weed 

control here. The abaence of'an appreciabie amount of chickweed in the 

experimental area is probably the reason weed control was not improved with 

the addition of eIPC. All treatments conteining less than 2 lbs. of CDRC 

were not considered all givinsa"eptable weed controL This would suggest 

that, at least., 2 Ibs~ per acre of CDECare needed for effective henbit control 

through the ~inter; 

, table 3. Treatments end results of post-emergence trials in spinach location 

, Np. 1. 

Treat. Chemical and 

No. Rate/A in Lbs. Carrier 

1 

2 

3 

4 

5 

CDEC-2 

, cDEC-2 

EP'l'C-5 

EP'l'C-5 

CDEC-l 

CIPC-\ 

CDEC-l 

CIP'~-\ 

7 Check 

L.S.D. (5%) 

L.S.D. (1%) 

Water 

Attaclay (10%) 

Water 

Attaclay (5%) 

Wate~ , 

Attaclay (2%) 

Attaclay (\%) 

21 

11 

2 rows per bed 

- 1: complete ground cover of weeds 

10 : no weeds 

Weedproblem : chickweed (Stellsris media) 

Yield in Lbs. v,r Weed Contr~l 2 

30 ft. of bed! Rating at Hlryest- I 

75.4 

73.7 

83.8 

76.2 

76.7 

66.6 

73.8 

N.S. 

N.S. 

Table 4. Treatments and results of post-emergence trials in spinach 

location No.2. 

7.5 

8.8 

6.8 

7.2 

9.0 

9.5 

5.0 

L96 

2.69 

Treat. Chem1.c:aland Yield in Lb•. Wt. of Weedtlin .11 

No. Rate/A in Lbs. CArrie!' per 20 sg. ft. GramSper'aO sq. 'ft.- 

, ,''*, 

1 CPEC-2 Water 29.0 22.5 

2 CDEC-l Water 28.5 111.5 

3 CDEC-2 Water 32.8 20.0 

CIPC-1/8 

4 CDEC-l Water 32.8 75.2 

C1PC-1/4 

5 CDEC-l Water 30.7 78.5 

CIPC-1/8 

6 CDEC-l.S Water 26.5 67.0 

CIfe-1/8 

7 Check 32.2 191.0 

L.S.D. (5%) N.S. 105.0 

L.S.D. (1%) N.S. 143.9 

11 Predominantly benbit ~ amplexicaule)

516 ~'1.... 

Raiftf~ll record in inches for 1 ~. prior to and'3 wk. period fol16wing postemer8~~e 

treatments at location No.1 and No.2:' 1 ~k. pr~or ~.8fj'~~st wk. 

after ~, 2nd wk. after~, 3rd wk. after 0.36, 4 wk. to~al~4:~~. 

Summaryand conclu@ions for post-emergence triala 

(F> ., 

1. Old Dominion spinach WAS planted in the fall at two locatlbns, treated 

with one pre-emergence herbicide treatment, thinned or weeded 7 weeks 

later and given post-emergence treAtments of CDEC,CIPC and EPTC. 

Spinach had 4-6 trUe leaves at treatment. Granu,lar ,and spr4:f-tqrmul~ti9ns 

were compared at one location. Spinach was harvested the foild~in8··8pr'ing. 

Yield and weed control records were taken. 

2. The results indicate the very good possibility of using the pre-emergence 

herbicides CDEC,CIPC and EPTCas post-emergence herbicides to overwintering 

spinach at thinning or when the effects of the pre-emergence 

treatment is gone. The herbicide or rate to use would depend in part on 

the weed problem. At least 2 lbs. per acre of CDECwas needed for henbit 

control in this experiment while 1/4 lb. of CIPCwas sufficient for 

chickweed control in combination with 1 lb. CDEC. 

3. Granuler formulations appear to have more possibilities for this use. 

In addition to some better weed control would be the probability of leas 

residues to the crop with the granulars. 

4. It is possi~le that other leaf crops would also show a tolerance of these 

herbicides at some post-emergence stage of growth. 

S. It is suggested that work should be initiated toward the possibility of 

obtaining residue tolerances from Food and Drug for post-emergence use of 

CDEC,CIPC and EPTCon certain leaf crops. 

Literature 

Cited 

(1) DANIELSON, L. L. Evaluation of pre-emergence spray and granular 

applications of CDECon vegetable leaf and cole crops. Proc. of NEWCC 

1958: 17-22. 1958. 

\ 

-, 

"

CONTROLOF WEEDSIN TOMATOES ANDSWEETCORN1/ 

C. D. Price. Plant Physiologist 

Virginia Truck Experiment Station 

. Norfolk 

517 

,~ 

This paper presents the results of one experiment each on tomatoes and. 

sweet corn. Both e~periments were conducted on the grounds of the Virginia, 

Truck Experiment Station Eastern Shore SubstAtion at Painter during the 

summerof, 1958. 

Tomatoes 

Over 15.000 acres of tomatoes were grown·.commerc:l.allyin 1957 in the two 

county area comprising the Eastern Shore of Virginia. Mast tomato fields 

developed a rather severe weed.pro,b1embetween the last 'cu1tivation and 

harvest. And a1thougp badly needed. no herbicide is presently recommended 

for use on tomatoes during this period. The purpose. of this experiment was 

to add to the research information available concerning weed control in 

tomatoes in the hope of, soon having a herbicide. recommendation fer tomatoes. 

Experimental 

Informatiop, 

Tomato variety:' Rutgers •. fertilization: 500 1bs. 1Q~10-10.at transplanting 

and again after lay-by. Cultivat!on: All plots kept weed-free b~ regular 

cultivation to lay-by. Date· of lay-by: June 17., Date of.herbicide treatments: 

June 19. Temp. at treatment: 75°F. Soil moisture at treatment: moist. 

Plot size: one 6 ft. row with 12 plants spaced 3 ft. apart. Herbicide 

treatments: See Table 1. Area harveste~: 10 plants per plot. Experimental 

design: Rand. bloek with 5 reps. Methods of E\\12.l.:l.cation: Sprays applied 'in 

23 gals. water per acre as a directed spray with 49 x 49 non-clog 120 0 nozzles 

at 30 PSI. Granulars applied over top of plants with a tractor drawn 

applicator carrying 6 ft·. cut. 

Temperature record for 3'week period following treatments in degree hours 

above O°F: lstwk. 10.908. 2nd wk•. 1l199~. 3rd wk. ~. 3 wk. total 

35.559. 

Rainfall record in inches for 1 wk. arior and 3 wks. after treatments: 

1 wk•. prior ~. 1st wk. after 1.14. 2nd wk. after 0.64. 3rd wk. after ~, 

4 wk.· total 3.40.· 

1/ Contribution 'from the Plant Physiology Department. Virginia Truck Experiment 

Station, Norfolk. Paper No. 128. Journal Series. Approved for publication 

November24. 1958.

In Table 1 are shown the yield totals and weed control ratings fore8ch 

herbicide treat~~nt. All treatments were applied at lay-by and none of the 

treatments significantly affected the yield of No. 1 tomatoes or the total 

yield of all sound tomatoes. The major weed problem in t.his experiment was 

crabgrass (Cigiter!! sanguinelig). A weed control rating of 7.0 or above 

was~onsidered as being commercially acceptable. All treatments gave 

accepeableweed control. 'EPTC at 6 Ibs , per acre applied in granular form 

was th~only treatment to give 1007. weed control in all plots. 

CIPC at rates of 2 and 4 Ibs. and CDEeat the 4 lb. rate were compar~d 

as a directed spray and in granular form applied overall. In each caSe 

where granulars and sprays were compared at the same rate, the granular 

treated plots tended to out yield the spray plots. the weed control was also 

a little better in each case on the granulai treated plots. these results 

agree closely with the findings of Meggett( ). ; 

Since granular CIPC up to 4 Ibs. has received approval from Food and 

Drug' (2)" for use on tomatoes at lay-by, emphasis for the present should be 

placed on the results of th'e granular CIPe treatments. The 4 Ibs , per acre 

treatment did tend, although not significantly, to reduce tomato yields. 

The 2 Ibs. treatment gave negligible yield reduction with satisfactory grass 

control. It would appear that the 2 lb. rateof'granu1ar CIPC is the treatment 

that would have possibilities for use by the tomato grower at the present 

time. 

' 

Table 1. Lay·by herbicide treatments to tomatoes-and results. 

Chemical Yield of No. l Total Yield of 

" .u:t1ve .,.. tee,1la I t-..toa. 10 We•• '3' 

Rate/A •. , lorau1atioa Carrier Ups./10 :nant!! ' Lb./10 Plantsi- I latlpgs-' 

CIPC-2 Gran. (5%) Attaclay 66.58 89.80 8.8 

CIPC-4 Gran. (5%) Attaclay 58.08 81.88 9.2 

CIPC-2 Spray Water 59.18 84.38 8.2 

CIPC-4 Spray Water 55.20 77.78 9.0 

CDEC-4 Gran. (10'7.) Attaclay 69.38 92.18 9.4 

CDEC-4 Spray Water 65.26 87.40 8.4 

Neburon-4 Spray Water 63.82 ' 87.96 9.8 

EPTC-6 Gran. (10%) Attaclay 62.06 83.98 ,1.0.0" 

G 27901-1- Spray:" Water 66.36 88.16. 8.8 

Check 70.40 92,.92 ,2.6 

L.S.D. (5%) N.S. N.S. 

1/ All sound tomatoes that were approximately 2 inches in diameter or over. 

1/ All sound tomatoes. 

1/' 0 • complete ground cover of weeds. 

10 = 

'- 

no weeds.

SUmmaryand Conclusions 

519 

1. Rutgers tomatoes were treated at lay-by with spray and granular applications 

of CIPC and CDEC,with sprays of Neburon and G-27901 and with 

granular EPTC. 

2. No herbicide treatment significantly reduced yields and all treatments 

gave satisfactory weed control, predominantly crabgrass. EPTCat 6 1bs. 

gave 100%weed control on all plots to harvest. 

3. The most promising treatment for grower use at the present time is 2 lbs. 

per acre of granular CIPC. 

4. CDEC,Neburon. EPTCand 0-27901 look promising for weed control in 

tomatoes at lay-by and research should be continued using these herbicides. 

5. Granular formulations of CIPC and CDECgave slightly'superior results in 

terms of yield and weed control over comparable rates of sprays. 

Sweet Corn 

In the 1958 sweet corn variety trials conducted at the Painter substation, 

17 different herbicides, herbicide combinations and herbicide rates were 

tested. The variety trials consisted of three row p10ta and the third row of 

each plot was treated with a pre-emergence herbicide leaving two rows for a 

cultivated check. Eight variety plots were treated with each herbicide 

treatment. A particular sweet corn variety mayor may not (usually not) have 

been duplicated within each treatment and mayor may not have been duplicated 

between treatments. The purpose of this experiment was to get leads on any 

new herbicide or any herbicide combinations in terms of degree and length of 

weed control and its effect on as many sweet corn varieties as possible. The 

results obtained were for the most part observational and no statistical 

analysis was run. 

The results obtained with one of the 'treatments at two rates was 

considered of enough interest to report here. ' The 1 and 2 lbs. per acre rates 

of Simazine are t~e only two treatments that will be specifically referred to 

in this paper. 

Results 

And Observations 

Early in the sweet corn's growth it was evident that certain varieties 

were much greener and more vigorous in growth where treated with pre-emergence 

applications of 1 and 2 lb. rates of Stmazine as contrasted with the cultivated 

rows. This green color and stimulated growth continued through to 

maturity and was particularly striking on varieties Crookham 615-12 and 

Carmelcross. In addition, of the 17 treatments app~ied, the Simazine treated 

plots were the only plots that gave acceptable weed control past the second 

cultivation through to harvest. 

The contrast in growth rstes was so striking between the Simazine treated 

rows and the cultivated check for certain varieties that yield records and 

, i

n 

__ 

_1 

ft 

520 

certain measurements were taken on these varieties. "Eleven sets of data were 

kept for four var 4,eties treated with the lIb. rateand'ilJo1Tarleties treated 

with the I lb. rate. The results in terms of increased'husk~d'ear weight per 

acre and increased dozen ears per acre over and above the cultivated check 

are shown in Table 2. ('!') , , ' 

The results shown in Table 2 confirm the observation that varieties 

Crookham615-22 and Carmelcross were possibly stimulated by a l' lb./A. preemergence 

treatment of Simazine. Each variety showed an increage 'of"4l5 dozen 

ears/A. of marketable corn over its cultivated check row. The only variety 

that could be compered with both the 1 and 2 lb. rates was Atistogold and both 

plots showed identical increases of 207 dozen ears/A. over its cultivated 

check. However, the 1 lb. rate increased the ear weights by 1,792 pounds/A. 

as compared to an increase of 896 pounds for the 2 lb. rate. 

At best these results can only be considered as an indication of stimulation 

since in most instances only one replication of each variety was available 

for yield results. However, it is believed that the indications of 

stimulation from these pre-emergence treatmenta of Simazine are strong enough 

to suggest that they may be real. 

Table 2. Sweet corn per acre yield increases on Simazine treated plots over 

and above the cultivated check. 

Variety 

Crookham615-22 

carmelcross 

Iochief 

Aristogold 

Golden Hybrid G 101 

Silyzin e 

Weight of 

Husked Ears 

in Lbs./A. 

2,937 

4,381 

1,543 

1,792 

1 Lb./A. 

Dozen 

Ears/A. 

415 

415 

166 

207 

S1m4zine 2 LbS.lA. 

Weight of ' 

Husked Ears Dozen 

in Lbs./A. Ears/A. 

896 

1.643 

207 

249 

SUmmaryand Conclusions 

1. Simazine at 1 lb. per acre applied pre-emergence to several'varieties of 

sweet corn gave perfect weed control up to harvest with no injury to any 

variety tested, The 2 lb. rate gave perfect weed control through harvest 

with no varietal d~mage. 

2. Certain sweet corn varieties appeared to be stimulated by the S1Mzine 

treatments. 

3. Oata are presented which8uggest that 80&1estilllUlation did occur. further 

" "UP~I'~QeI "UJ,'be, ~ece•• ~ry" to" ~C?~l~~l"ly 

certain'sweet corn v8r~etie~ ~,o~iirlaz1ne., 

I'elat.thf .... t1._1"~en"b 

Literature Cited 

(1) MEGGITT,w.F. Progress report on herbicides for weed control in 

tomatoes. proc. of NEWCC1958: 92-95. 1958. 

(2) United States Department of Agriculture. CIPC. A summeryof certain 

ft __ ~~_~~_ 

1_L~ 

ft __ L~__ 

__ ~ 

__ ~ 

-

521 

EVALUATION OF CERTAINGRANULAR HERBICIDESON INJURYAND 

WEEDCONTROLIN TOMATOES 1 

BARRYa, HUGHES.C. J. 

NOLL.ANDM. L. ODLAND2 

One of the main' factors in the high cost of growtng tomatoes is the 

expense of manual labor in controlling weedlS. The uev

522 

WLE 

I 

Effect of certain granular herbicides upon weed control. yield. number of 

fruit, and weight per fruit 1.n tomatoes. 

Rate per . . . 

acre in Yield NQ.. Wt.1 

.!r~aJ;m~nJ; l b.! ._

ogress Report on Lay-by Weed Control of potatoes l 

R. ~. Sawyer, G. H. Collin and W. H. Thorne 2 

The work covered in this report is a continuation of the lay-by 

investigations, reported in previous proceedil~s. The main interest is in 

potato tolerance to materials which have a proven history of weed control. 

Materials 

and Methods 

Katahdin tubers were planted April 14 and given normal culture until 

lay-by herbicides were applied on July 2, 1958. There had been three weedings 

and three cultivations at this time. 

Plots were three rows wide and 30 feet long with four replications 

of each chemical treatment in a randomized block design. There were check 

plots beside each chemical treatment. Plots were harvested on 3eptember 22. 

Storage results are given for the lay-by weed work reported in the 

1958 proceedings. Black spot index was obtained by bruising tuber and peeling 

after 48 hours. This index run~ °to 90)' taking into consideration both 

the severity of the black spot and the per cent of tubers sholving the blackening. 

The chipping index was obtained by frying cured samples and rating the 

color of the chips 1 through 9~ One indicated very dark chips and 9 very 

light chips with 5 considered the darkest level for commercial acceptability. 

Results 


None of"the materials statistically affected the yield. Dalapon, 

however, gave indications that even with the granular application there was 

some yield depression as found in previous years with the overall sprays. 

There was insufficient weed problem in these plots to take weed data. The 

yield results are given in Table 1. 

The storage results given in Table 2 are for those materials 

reported on in the 1958 proceedings. None of the materials had any effect 

on black spot or chipping color. As the dosage of ...

524 

Table 1. Effect of several lay-by hE>l'vjcic1eson yield of Katahdin potatoes. 

~~~ri~l§ 

~§~~_1Q§£L~~ 

Alanap 2 Spray 4 

Alanap 3 Granular 4 

Diuron Granular 3/4 

3Y9 Spray 4 

3Y9 Granular 4 

EFTC Spray 5 

EFTC Granular 5 

EFTC Spray 10 

EFTC Granular 10 

3imazin Spray 1! 

. 3imazin Granular li 

Da1apon Granular 1+ 

Check 

~y.!.Lg_g:J!~_ 

467 

477 

442 

508 

512 

454 

501 

492 

467 

469 

470 

439 

400 

Table 2. Lay-by weed control (storage rE'su1ts) 

Per cent Black Chipping 

Ir~~E~~t§_______________________ 

~h~iU~~g~____§U:2Yt~Dg_____~~2t____~~1~t____ 

Spray or 

Hetli!ri~l____l2§L~____Or5Hnll~_ 

Alanap 2 4 S 6.2 14.6 40.9 5.5 

A1anap 2 6 3 5.9 13.7 35.2 6.0 

Alanap 3 !~ G 6.8· :1,2..4 3008 5.8 

Alanap 3 6 G 6.5 12.4 30.8 6.3 

... 6.0 12.8 35.2 5.0 

" 

Natrin 4 

rJatrin 8 S . 5.6 11.2 . 24.8 5.3 

Diuron i- S 6.2 1403 42.1 5.5 

Diuron 3/4 S 7.2 14.3 39.4 5.5 

Diuron 

G 6.2 13.8 35.8 6.5 

Diuron G. 6.3 15.4 32.2 405 

JI4 

Diuron 1 G 7.0 14.1 36.9 6.3 

3Y9 3 S 6.7 14.2 3406 5.3 

3Y9 6 s 7.3 15.0 31.0 6.5 

Vegedex 6 S 6.9 15.7 32.7 5.8 

Vegedex 9 S 7.1 14.2 35.6 6.3 

EFTC 4 S 5.3 14.3 24.·9 6.8 

EFTC 8' S 6~3 14.1 45.6 6.0 . 

Check 6.3 14.3 38.7 5.5

A Report on the Use of Atrazine (Geigy 30027) 

Applied Pre and Post-Emergence in Sweet Corn 

527 

*By Norman J. 

8mith 

Problem 

An effective herb:l.cide which could safely be applied pre and post-emergence 

on sweet corn is warranted. 

Growers, due to wet soils or other delays occasionally miss the opportune 

time for pre-emergence applications. 

The readily aV/:l:!lable 2,4-D materials cause injury on many sweet corn 

varieties grown on light soils and do not control grasses. The Dimtro materials 

are effective when applied pre-emergence for many broad leaf weeds but the poor 

grass control is disappointing to growers. 

Materials 

and Hethods 

The sweet corn variety Iochief was planted July L Pre-emergence sprays 

were applied July 2. Post-emergence sprays were applied July 18. On July 18 

the corn was 6 to 8 inches tall with broad leaved weeds and grasses up to 

2 inches in height. 

The Atrazine (0-30027) was applied in an 18 inch band over 34 inch rows 

using a 4 nozzle low pressure boom sprayer with one nozzle over each row. 

Rates of Atrazine (G- 30027) applied were l'f:, 2t and 5 pounds actual per 

net acre. Net acre is that soil which was s.ctually sprayed. 

tall. 

The corn was thinned to an 18 inch spacing in the row When it was 10 inches 

Weeds present 

were: 

Broad leaf 

Red root pigweed (Amaranthus retroflexus) 

Lambs-quarters (ChenopodiU!Jl album) 

Ragweed (Ambrosia elatior) 

Purslane (Portulaca oleracea) 

COllllllOnchickweed (stellaria media) 

Grasses 

Crab grass (Digitaria sangu1nalis) 

Green foxtail (Setaria viridis) 

Barnyard grass (Echinochloa crusgal.li) 

Nut grass (Cyperus esculentus) 

*Assoc. County Agric. Agent, Nassau County, N.Y.

528 

Plots were 4 (34 inch) rows wide and 50 feet long. The front 25 feet of 

each plot received the pre-emergence treatments. The back 25 feet of each 

plot received the post emergence treatments. Plots were replicated four times. 

Four check plots included were each 50 feet long and 4 (34 inch) rows wide. 

Growing condit18ns were gOJd with ample rainfall through the complete 

season. Soil was a sandy loam. 

None of the sprayed or check plots were cultivated for the complete 

growing period. 

Results 

July 18 observations showed complete control of all brJad leaves in the 

pre-emergence July 2 treatments. Annual grass cootrol was complete except in 

the It- pounds plots. 

July 21 observations showed a complete burn on all of the broad leaf weeds 

in the post emergence July 18 plots. The Atrazine effect was very similar to 

a contact spray, such as Stodds,rd Solvent. 

The annual grasses showed a slight tip burn. 

The corn d1dnot show any effect from the pre or post emergence sprays by 

July 21 or thereafter. 

Whenthe corn in the check plots was 12 inches tall it began to show 

yellowing and tip burn on the lower leaves caused by weed competition. 

Weedpopulation in the untreated areas averaged 50 broad leaves and 10 

annual grass plants per square foot. An occasional nut grass plant was found. 

Rating of Atrazine WeedControl in the 18 Inch Row 

Sprayed Area - At Harvest Time 

Pre -emergence 


Pounds Actual lt 2t 5 lk 2k 5 

Broad Leaf Control 10* 10 10 10 10 10 

Annual Grass Control 10 10 .10 3 7 8 

Nut Grass 1 1 3 1 1 3 

*Rating numbers are 1 through 10. Ten is complete control and 

1 no control.

529 

Rating of Atrazine Weed Control in the UNSPRAYED 

Area Between the Rows - At Harvest Time 

Pre-emergence 


Pounds Actual l± ?! 5 It ?!- 5 

Broad Leaf Control 1* 8 8 1 8 8 

Annual Grass Control 2 6 6 2 6 6 

NUt Grass 1 1 1 1 1 1 

*Rating numbers are 1 throush 10. Ten is complete 

control and 1 no control. 

The results indicated in the above chart are usually unique. 

It indicates an apparent lateral movement of the Atrazine 

Sweet Corn Yields 

and Response 

The yield of sweet corn in the pre and post emergence It, 2! and 5 pound 

plots was one marketable ear per plant. 

Yield of sweet corn in the untreated areas was zero. No ears could be 

found which were satisfactory for market. Most ears were less than 5 inches 

long and 3/4 inches in diameter. 

At no time was any adverse affect noted in the sweet corn which was treated 

pre or post emergence. 

Conclusions 

Yields of marketable sweet corn, one ear per plant, were obtained during 

Atrazine (G-3002'7) pre and post emergence without cultivation. The pre-emergence 

treat.nts were most effective for grass control. Pre and post emergence 

treatments were equally effective for annual broad leaf weed control. 

Some degree of weed control was obtained in the unsprayed areas adjacent to 

the sprayed areas. 

S1JDlIll8I'y 

Atrazine looks promising as an effective herbicide for use in corn. The 

It lb. rate controlled all broad leaf weeds and annual grasses when applied 

pre-emergence. 

. The It lb. rate controlled all broad leaf' weeds when applied post emergence 

when corn was 6 inches tall. The 5 lb. rate applied post emergence gave

530 

THEMANAGEMENT OF THEROADSIDEBYSELECTIVE 

HERBICIDETECHNIQUES 

Richard H. QOOdwiu! 

William A. Niering 

Thi.:o paper des.Le 'vith prob Lema resulting from the improper apjLi.catdon of 

'Ieed killers on our roadsides and recommends eco.Logi cs.Hy and economfcal.Iy 

sound menugemen't tc(;nniques. The r econmendatd.ons ar e generally appl.Lcab'l.e 

to p11 types of roudsides, but are especially directed towPI'd two-lane town, 

county, or stde roade , These recommendations do not appIy to the mam'tent.n 

ce of the ~rpssy turf or to areas under the guard rails. 

,hat 1;, the Crisis? 

L Needless destruction of attractive r'oad si.de ornament.al, shrubs*, ',Iild 

flowers and other herbaceous flowering plunts frequently referred to 

as "noxious weeds", which, if spared, would enhance the beauty of the 

roadside. 

2. Inadequate root-kill of the sprayed trees and ShI~bs (brush) on initial 

application so that repeated treutments are required. 

3. The spruying of ragweed, a tecbnique biologically unsound asa,method 

of eradi~ation and with unfortunate side effects listed under item 

one above. 

4. The cres::i'm of continuous unsightly b rown SWIJ.thsalong roadsides, 

which result from broadcast spray techniques. 

5. Attracti ve 10'7 price-per-mile bids offered by per-sons careless of 

desirable ~lGnt types being sprayed. 

boudside 

l~eeds. 

L Ao.equote \isibility and good sight line conditions, ~rhich necessitate 

remonl of certain woody growth aLong the roodsd des , 

2. The ez-addca tion of poison ivy. 

3. A rou.dside attractive to the moteY'ist, 'whet.her- tie be on: vacatd.on or 

merely commuting to and from work. 

1 rrofessor of Botany and Director of the Connecticut Arboretum. 

2 As~ociate frofessor of Botany and Assistant to the Director of the Connecticut 

Arbo:r-etum. 

* Jl.zaleas, mountain laurel, blueberries, dogwoods, viburnums, bt.yberry, winter- 

b er rv and others.

531 

4. The accomj.Li.ehmerrt of the foregoing objectives at a n,iniluum cost. 

j, 5dective yet I!.conomical Approach to the Problem. 

Th..:-~;LLL(;TIVl!. j\Pr'ROACHimplies removing only those woody plants which 

either (r.) irltprfere with sight line conditions or (b) are otheI'1l"ise 

undesir~hle (e.g. poison ivy). This involves treating the un~esirfble 

woody plnnts selectively rather than by non-selective broadcast or 

blanket srray techniques now commonly employed. 

A. 1.1fJnugementof Roadside "Brush". 

"long most roe.dsides they'e is a mowed strip of vDrying width f.nd/or 

u brushy margin dominated by a mixture of trees and &hrubs. The 

former is often narrow along to'.VI1roads with the "brush" (trees end 

shrubs) encroaching right to the edge of the road. Since tree 

sprouts which occur as clumps, resulting from previous cutting, often 

obscure visibility s.nd their branches tend to grow out into or Lean 

over the road, it is u common pr~ctice to eliminate such tree growth. 

however, the associated shrubs need not be eliminated unless they 

interfera ~ith sight line conditions by their occurrence in the mowed 

strip immediately next to the road or on the inner sides of curves. 

ciy em~loying this selective approach, many attrcctive broad-Iesf 

flowering plents frequently referred to as "noxious '

532 

b. Poi~on Ivy Tre~tment. 

Poi son ivy can be specifically sJ?rt>yed during the summer 'vith 11101n,, 

triozole or 2,L.,5-T, following the directions pr escr-fb ed on thE.:label 

or tret'ted during the winter by a bark sprey ucmg the 2,4,5-T formulation, 

given above. 

G. Ragweed tradication.--Ragweed, being an annual pl.ent , requires open 

soil for its seeds to become established each year. Therefore, 

by creating a dense continuous cover of other species 

(perennial grasses and broad-leaf flo1vering rlants), r-agweed 

is permanently eliminated. At the edge of the pavement, there 

may be an area receiving such serious disturbance as to prevent 

the establishment of continuous cover. 1'1/henevermowing 

cen not be sufficiently ftoequent, a light folisde spray £Q!l::. 

fined to this narrow strip may, under certain circumstances, 

be useful as an annual procedure in controlling ragweed. 

Hecomncnded 

anugenen t Techniques. 

1.) ll~~OUnAG~ DENS~ COV1Rwhenever possible of ~erennia1 grLss~s 

and broad-leafed flowering jJl!'nts in the mowed stri j ; . 

2.) ;,t)iITNG,especially during late summer rrior to the flowering 

of ragweed, is recommended. This will prevent pollen formation 

of Bny rag ....eed which may still be present in the mowed 

area. 

J.) DONOTUb1 FOLIAGJi,SPRAYSany further back from the margin 

of the pavement than necessa:.y. Such!l spray kills the 

ragweed that particular year, but the soil is opened up and 

exposed for ragweed seed to grow there in subsequent ses.eons , 

It may even be more abundant following trea,tment, since the 

broad-leafed perennials are very sensitive to the spray End 

"'ill be eliminated, thus exposing more soil for ragweed. 

I..) T& CHUP1ST lVAYTO ERADICATiRAG'&ED1& TO j"j~COURp.m. OTHiR 

PLiiliTGTO CROWDIT OUT. 

The Accomplishments of these Techniques. 

1. 

. 

.) 

~ 

]. 

Only the undesirable woody species a16 removed. 

Ragweed is eradicated • 

Attractive nu.tive plants are prtlservlod to enhlince the I'oadf:lides. 

unsightly brown swaths are minimized or eliminated. 

5. Fewer treutments will be needed to accomj.Lt sh the oejectives,_ 

since better root-kill is obtained. The initial cost of the 

--, - _ .. ..:•• -. ....__ ......._- ....... ..._.~" ""'_ \..4 _"""__ ....t... ..._ ... l.-. ...... +' ...._

533 

WEEDCONTROLIN CARROTS- 1958 

W. H. Lachman and L. F. ~1ichelson* 

Massachusetts Agricultural Experiment Station 

Amherst. Massachusetts 

The use of Stoddard Solvent for killing weeds in carrots 

has been a standard 

a few weed killers 

practice for about twelve years. Recently 

have been developed that offer promise of 

killing we~ds in carrots (1). Accordingly tests were made using 

these products and this paper reports some of the results of the 

trials. 

Materials 

and Methods 

The plots were located on a Scarbo~oush fine sandy loam 

soil which was well prepared and seeded to Chantensy carrots on 

June 23. 195il. The soil was relatively moist at the time of 

planting and. later frequent rains maintained ideal conditions for 

the development of the crop. 

Twe1v~ treatments and a check were included in the tests 

and each oi the treatments were replicated four times. The three 

treatments involving G-30028 were applied pre-emergence immediately 

after planting. The other nine treatments involving the materials 

G-3003l. N-4562 and Sovasol No. 5 (Stoddard Solvent) were applied 

post emergence on July 10. 1958. seventeen days after planting 

when the we.ds were approaching two inchus tall. All of the 

msterials except Sovasol No. 5 were diluted with water and sprayed 

on the plots at the rate of SO gallons per acre; the Sovasol No. 5 

at 100 gallons per acre. 

The weed population consisted of purslane. smartweed. lamb's 

quarters. galinsoga. pigweed and crabgrass. Shepherd's purse and 

ragweed were not present. The readings on weed control. height, 

crop stand and vigor were made on July 28. '1958. All of the plots 

were cultivated on August 5 and again on August 15. The carrots 

were harve~ted and weighed on October 17. 1958. 

Results 

The results of the ·tests are presented in Table 1 where highly 

significant differences are displayed among many of the treatments 

for weed contrel. stand. vigor and yield of the crop. 

*Thanks are due to the Geigy Chemical Corp. and the Niagara Chem. 

piv. of Food Machinery and Chem. Corp. who supplied the weed·killers. 

Contribution No. 1180 of the University of Massachusetts, College 

of Agricultu::e. Experiment Station. Amherst,. U811sachusetts.

Table 1. Effect of Chemicals on Weed Control Growth and Yield of Carrots 

(Figures are the means' of 4 replication&) 

Planted June 23. 195& - Recorded July 28, 1958 

VI 

W 

+- 

1,oieedControl Ta1',u,t Carrot

535 

It was apparent that 4.0 pounds of G-30028 and 3.0 pounds 

of N-4562 were tOKic to carrot growth and vigor. These two treatments 

resulted in the lowest crop production in the test. Treatment 

12, i~. 100 gallons of Sovasol, No,S, resulted in good control 

of weeds'lwith production not significantly different from the best 

yields. 'Th$ two materials, G-3003l and N~4562 appear to offer, 

excellent promise as herbicides for carrots. 'In these tests 1':2, 

pounds of G-30031 and 1-4 pounds of N-4562 controlled we~ds very 

well without significant effect on ere? yield. The treatments did 

not appear to affect the quality or appearance of either the tops 

or roots of the crop. The effects of various climatic influences 

and the uniformity of behavior of these chemicals should be assessed 

in more widespread and repeated tests. 

Summary 

Good control of many annual weeds resulted from post emergence 

sprays 0'£ G-30031 and N-4562 on plots of carrots. Further work will 

be neceseary with these chemicals before definite recommendations 

can be made. 

Literature 

Cited 

1. Lachman, W. H. et al. Weed Control in spinach, lettuce and 

carrots, 1957. Proc. N.E,W.e,C. 12:399-401. 1958.

536 WEEDCONTROL IN SWEETCORN- 1953 

t~. H. Lachman and L. F. Michelson* 

MASSACHUSETTS AGRICULTURAL EXPERIMENT STATION 

!\mherst, Massachusetts 

Test on theeffe~tiveness of herbicides in sweet corn have been conducted at 

this station 'for many~years. These tests have ineluded coopelatlon·iccountry-wtde 

test programs and evaluation of many chemicals as weed killers when made available 

by the chemical industry. By bracketing the ratee as suggested by theaanufacturer, 

we have also been able to aGcsrtain the best rates to use for kilUng"weeds under 

the conditions prevailing at Amherst. Massachusetts. T1~ispaper presents the 

results of. testing some of the ,newer chemicals during 1958. ", 

~~terlals 

and MethoQs 

Twenty treat~~nt~ ~nvolvlng seven chemlcals were applied to plots of Seneca 

il~auty sweet corn; che treatments were replicated four times. Each plot consisted 

of four 18-foot rows. The seed was planted by haud, wlth the rows spaced 3 feet 

apart and the hills 3 feet apart ln the row. The so11. a Scarborough very fine, 

sandy lo~, was prepared ln the usual manner, Bnd a 8-16-16 fertilizer waa broadcast 

at the rate of one ton per acre. The co~n was planted on June 17 in rather 

dry soil. The Boil remained d;,;y until June 24 when there was 0.13 inch of precipitation 

and again on July 5 wha:l 0.34 inch fell. Preci.pitatiCln during June was less 

than half that normall;; expected. during July and Auauot 25 per cent more than 

normal, and in September a per cent greater than th~t no~ally expected. 

All of the-.chemicals were applied pre-emergence on June 19, two days after 

planting. The various chemicals with tneir respective per-acre rates of application 

are listed in columna 2 and 3 of Table I. The wae~ killers we~e diluted wlth water 

and applied at ;re rate of 50 gallons per acre. lhe sprays were ap?lied with a 

Brown Open~Hed No. t, hand-pressure sprayer Htted wlth a No. 8004 Spraying Systems 

Tee Jet, fan type n02z1e. 

The weed population consisted largely of red, root pigweed but also with soce 

mixture of purslone, e~artwe~d, lamb's ~uarters, galinsoga a~d crabgrass. The 

readings on weed control and weed helght were made on :uly 21 and then the plots 

were side dressed with 400 pounds of 10-10-10 fertilizer and cultivated twice prior 

to lay-by. The stand of cc~ ~as ~ulte variable but growth and appearance of the 

crop was good. 

Results 

The results o£ th~ tests are presented ln Table 1. Highly significant 

differences are displcyed among the treatments for weed control and weed height 

while no significance can be ascrlbed to differences occurring among ~he plots for 

number of marke~able ears or plot yields. 

*Thanks are due to the American Chemlcal Co•• DowChemlcal Co•• Geigy Chemical Corp., 

~nd the Monsanto Chemical Co.! who kindly supplied the varlous weed killers. 

"""...,...",,......I'to_MAo '1A1,..~ .. "'.~ n....f ... .aor-af • ...,. ft~ 'Maafta"hu"a .... 8 t'",,11cftlA Af ADPof,.."lfonPA_

TIIBLE I. Effect of Chemical on Ueed Control and Yield of Seneca Bea.at} Sweet Corn 

Planted June 17. 1958 - Treated June 19. 1958 ':"'Recorded July 21. 1958: 

Rate t~eed Control Tallest Marketable 

per acre 1 Poor to Weedl;leight Ears Plot Yield 

Plot -- Treatment 

Lbs. active 9 Excellent :' Inches per Plot 

Lb 

l~~ -- -. 

. 

1 Si.lllazine 4.5 . g-~O 53 37.4 

2 Simazine 1.5 5.8 6.8 46 31.6 

3 Simazine 2.0 7.0 4.1 46 33.5 

4 G-21901 1.0 4.3 6.& 49, 34.0 

., 

5 G-21901 2.0 1.0 

5~4 51 35.6 

6 G-21901 

. 

4.0 9.0 o 5 50 35.2 

1 G-30021 1.0 6.5 6.5 50 36.6 

8 G-30021. 1.5 8.5 1.8 47 33.0 

9 G-J0027 2.0 9.0 0.5 43 34.4 

10 VeRedex 6.0 1.0 3.8 49 33.7 

11 Vee:edex 9.0 8.6 0.8 50 35.0 

12 Randox 6.0 4.5 6.3 51 35.3 

13 Handox 9.0 5.8 5.5 45 31.0 

14 DNCPremerlle) 6.0 4.3 .• 9~0 47 32.4 

15 CDM-T 2.0 .. 5.5 1.0 45 31.8 

16 COM-T 4.0 6.3 4~0 49 32.6 

17 CDM-T 8.0 6.5 1'3 - 41 32.2 

18 ACP M-503 4.0 2.5 - 11.3 42 27.0 

19 I\CP 1-1-503 8.0 2.5 10.0 ':, 40 25.9 

20 Check - --- 1.0 • 13.8 46 30.7 

L.S.D. C?.05 -- 1.1 2.1 N.S. N.S. 

L.S D. f' .01 2.3 3.7 N.S. N.S. 

\J1 

W 

---.}

I 

I 

t 

I 

~ : 

• I 

:,\ 

i 

\: ~;' ~t: 

~. 

.r'I.', 

I. 

: t ,i 

It is very readily apparent that the "Trieaine" compounds and CDAII.-T, (Randox 

formulation T) were esp~cially effective in preventing weed growth. Plota which 

were treated with, four pounds of 0-27901 and two pou'ada of 0.-30027 were practically 

free from all 'weed growth five weeks after treat~.t. Under similar conditions 

Simazine did not per~o~1 quite a. wall nor was its performance as noteworthy as in 

1957 (I), a year when soil moisture conditions were more favorable at the time of 

application. t ,-' 

It was clear that pound for pound'Vegecl.exwas markedly mars effecdve ehan 

Randox, but as indicated above~ Randox' - T (CDAA-T)st 8 pounds per acre was one of 

the outstanding treatments in the test. 

The results from the DN(Premerge) treatment were not particularly noteworthy 

and treatments using ACPH-503 were not significantly better than the check. Yields 

from the a pound treatment with ACPM-503 were the \~weat of any treatment but none 

of the differences among the tre4tments should be considered as aignificant. 

Sw/pary 

Certain Triazine compounds (0-27901 and C-30027) and aendoK formulation T were 

especially noteworthy in their sbility to prevent weed growth in plots of sweet 

corn without affecting the yield of the crop. Thia was in a year when soil 

moisture conditione were not optimum for best results with the standard pre-emergence 

herbicides for corD. 

Literstu::-e ~ 

1. Lachman, W. H. lind Mlcbelllon, L. F. WeedControl in Sweet Com - 1957. Proc. 

I. E. w.e.c. l2:38~-385. 1958~' 

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Vol. 13â1959 - NorthEastern Weed Science Society

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Vol. 13â1959 - NorthEastern Weed Science Society