2. Introduction
• Chestnut trees are growing in temperate climate of the world for
more than 4000 years for beauty, fuel and shelter
• Sweet chestnut is nutritious low in fat and rich in vitamin B
• Freshly harvested nuts contains 50% moisture, 40-42 %
carbohydrates, 2.9% proteins and 1.5 % fats
• Its wood is durable and used for timber and furniture work
• Chestnut contain little oil and are high in carbohydrate particularly in
starch
2
3. Taxonomy
• 2n= 12
• Family :Fagaceae
• Genus :Castanea
• Species
• American chestnuts
• Castanea dentata (American chestnut – eastern states)
• Castanea pumila (American or Allegheny chinkapin, dwarf
chestnut – southern and eastern states)
American chestnuts
3
5. Contd…
• The European chestnut
• Castanea sativa (sweet chestnut,
Spanish chestnut)
5
6. Climate
• Can be grown in a wide range of climate in temperate areas
• Hardy as peach and can withstand as low as -29oC temperature in
deep dormancy
• Requires less chilling to break bud dormancy in spring
• Buds respond quickly to warm temperature and become subject to
damage by late spring frosts
6
7. SOIL
• Chestnut can be grown in all types of soil but grows best in well
drained sandy or sandy loam soil
• Soil should be moderate to slightly acidic
• Chestnut trees withstand moderate drought after well establishment
7
8. Rootstocks
• Species of chestnut are used as rootstock
• Mixed hybrid strains should not be used as rootstock-cause graft
union failure
• After harvest seeds are stratified for 50-60 days in moist sand at 0-
2.2oC to break dormancy and ensure uniform germination
• Stratification in moist sand kept in wooden boxes at cool shady place
is better than in refrigerator - fluctuating temperature under field
condition promote seed germination
• Stratified seeds are sown in nursery beds March
8
9. Propagation
• Grafting
• Splice grafting and tongue grafting
• Done in March
• Budding
• Chip budding
• Early grafting- harmed by spring frost
• Pencil thick one year old root stock is used
9
11. Planting
• Planting is done during winters
• Before planting, the site should be properly laid out with contour or
terrace systems
• The pit should be prepared well in advance and refilled with soil
mixed with 60 kg well rotten FYM
• Plants spaced about 30 feet apart
11
12. Manures and fertilization
• Chestnut trees are mostly planted on eroded upland soils, so it is
important to fertilize trees regularly
• At least ½ kg 15:15:15 NPK mixture per year age of tree should be
applied before sprouting or in early spring
• Full bearing trees should be supplied with 100 kg FYM and 6-8 Kg of
NPK mixture during December – January
12
13. Training and pruning
• The Chinese chestnut form a low headed tree if left unpruned,
unpruned tree start bearing earlier than severely pruned ones
• Early pruning stimulates vegetative growth, hence, for early nut
production orchard trees should not be pruned for few years
• Allow the trees to come into bearing before any pruning is done, then
remove only a few of the lowest branches each year until the tree is
properly headed
• Lowest branch kept at a height of 1m from the ground and branches
should be spaced spirally at a distance of 40 cm from one another
13
14. Flower and fruits
• The Chinese chestnut is latest tree to bloom
• The flowers are produced in two kind of catkins borne on current
season shoots near the terminal portion of the shoot
• The fruit of the Chinese chestnut is borne in a spiny involucre known
as bur
• Three nuts are usually produced in each bur (upper, left and right )
• The bur is a vegetative structure that encloses the nuts or fruits
• Botanically, each nut is a complete fruit
14
15. Contd…
• The shell of the nut develop from the ovary wall
• The kernel of the nut is a young embryo plant that develops from the
fertilized eggs of ovule
• The edible portion of the kernel is made up of two fleshy cotyledons
and minute internal growing points of shoots and root
• The kernel is enclosed in a membranous covering called the pellicle,
which originate from the integument of the ovule
15
16. Pollination
• All cultivars and species are self sterile
• Two or more cultivars and seedling must be planted to ensure cross
pollination
• Young orchard trees may not set nuts when the first flowers are
formed because of lack of pollination
• wind pollinated as well as insect pollinated
16
17. Harvesting
• Mature in the first fortnight of October in Himachal conditions
• The bur colour changes from green to light brownish and split open
during maturity releasing the nuts
• Chestnut are very perishable crop that require prompt harvesting
every third days
• Traditionally, chestnut are hand gathered from ground after falling
naturally
• In developed countries the chestnut are harvested mechanically by
shaking the burs from the trees
17
18. Contd…
• The harvested chestnuts are treated with fungicides to prevent
spoilage.
• These nuts are then cured for 5 days at 21oC
• Harvest period of each tree is 23 days as maturity is not uniform
• Seedling tree yield 26 kg of nuts at 12 years of age
18
19. Storage
• Nuts are highly perishable because it loose moisture rapidly at room
temperature, causing the kernel to become hard and inedible
• Nuts with 10% moisture stored at 0°C and 70% relative humidity
• Mold on chestnut can be destroyed with hot bath (57.7oC for one
hour)
• The best way of drying chestnut is to put them in bags at 4.4oC with
well circulated air at 70 % relative humidity
19
