The Chinese Chestnut (Castanea mollissima) is a medium-sized shade tree that bears nutritious nuts and has a spreading habit. At present, these native Chinese trees are becoming increasingly popular as cash crops. Their nuts appear in spiny burs that open up on ripening. Each bur contains one to three shiny, dark brown nuts.
Soil and Water Requirements
These shade trees grow best in loamy to sandy loam soils that are well-drained. The soil should be slightly acidic (pH 5.5 to 6.5).
These trees can tolerate extreme temperatures of up to 20°F when they are completely dormant. However, it is advisable to avoid frost pockets at the site of plantation to prevent injury to the swelling buds.
The site chosen for plantation should have a summit and shoulder slopes for maximum air drainage and protection from winter and early spring frost injury. Once the trees are established, they are drought tolerant, but require ample water during the growing season. The maximum yield is obtained under optimum soil and water conditions. Deficient water supply during mid-August results in smaller nuts, while the lack of water in September can prevent the burs from opening normally. Micro-irrigation is the best suited technique for chestnut plantation.
Tips on Cultivation
The trees can be cultivated by directly planting grafted trees, by planting nuts and graft fielding them after one or two years, or by planting seedling trees and grafting them after one or two years. The method of cultivation should be chosen according to the skills of the grower and the economic conditions. Planting grafted trees is the easiest method of establishing a Chinese Chestnut farm. The grafted trees begin to bear nuts in two to three years. The time taken to bear nuts also depends on the growth rate of the trees.
Transplanting should be done in early March when it is easy to work on the soil. Special care should be taken to keep the roots moist while transplanting. The treetops and rotten roots should be pruned regularly. The transplanting hole should be free of fertilizers and soil amendments. The tree should be watered after transplantation. 30-by-30-foot spacing is required between the trees. As the trees grow, every tree on the diagonal should be removed to increase the spacing to 42-by-42 feet.
The trunks of young plants are susceptible to sunscald. It is advisable to paint the trunk with a 50/50 mixture of white interior paint, and then, water and cover it with a white plastic spiral tree wrap to avoid injury.
Mulch should be applied on a 6-foot circle around the tree to prevent other vegetation from growing. Every time the tree grows a few inches, half a cup of ammonium nitrate fertilizer should be evenly applied over the mulch. The plant should be watered regularly during the summers to keep the soil moist.
A Chinese Chestnut farm usually remains pest-free. In well-managed areas, the chestnuts can be grown without any pesticides. It is a good idea to surround the plantation with a 5-foot welded wire cage to keep animals from grazing. If the crop gets infected by caterpillars or weevils, application of effective insecticides becomes necessary.
Harvesting is usually done in September or October. The fallen nuts should be harvested promptly to avoid predation from animals. The nuts should be removed from the burs and refrigerated in sealed plastic bags to avoid molds. Once the collection period is over, the chestnuts can be sold locally.