Castanopsis chinensis Seeds | Chinese Chinkapin
LATIN NAME: Castanopsis chinensis
COMMON NAME: Chinese Chinkapin
Plant Profile
Chinese chinkapin is a canopy tree of the evergreen forests of southern China, and it is one of the species that defines what those forests look like. It grows twenty to thirty metres, with a straight cylindrical trunk, a dense crown of leathery, lance-shaped leaves that are dark above and paler beneath, and a bark that is grey and smooth when young and breaks into shallow fissures with age. The flowers are small and yellow-green, in upright catkins, and the fruit is a cupule covered in short spines that opens to release a single glossy brown nut. It is not a chestnut, though the nut looks like one and is edible after roasting. It grows in the lower subtropical zone, in Guangdong, Guangxi, Hunan, Guizhou and Yunnan, on acid red soils in humid, frost-free country, often as a dominant in the remnant forest patches that survive around villages.
Science & Biotechnology
Castanopsis chinensis is a member of the Fagaceae, in the same family as oak and chestnut, and it is one of the species that make up the lowland evergreen broadleaved forest of southern China, a formation that has been reduced to fragments by centuries of clearing. It is monoecious, with separate male and female inflorescences on the same tree, and it is wind-pollinated, though bees take pollen from the male catkins. The species masts: it produces a heavy nut crop in some years and almost none in others, and the pattern drives the populations of rodents and birds that disperse the seed. The spiny cupule is a defence against seed predators that is only partly effective, since squirrels and rats gnaw through it. The wood is hard, moderately durable and used locally for construction and furniture, and the bark is rich in tannin.
Uses & Benefits
The nuts are edible and are gathered in autumn, roasted or boiled, with a flavour between chestnut and acorn; in some districts they are ground and used as a starchy food. The timber is hard and durable and goes into local construction, tool handles, and furniture, and it is one of the species used in the plantation forestry of southern China, though growth is slow. The tree is also planted for watershed cover and for the restoration of degraded hill land, where its deep roots and dense canopy rebuild soil. In gardens it is a large, handsome evergreen for frost-free climates, grown for the foliage and the spiny fruit, but it needs space and warmth. Tannin from the bark and cupules has been used for tanning and dyeing. It is not a substitute for the chestnut in cold climates.
Growing from Seed
Sow fresh nuts in autumn, immediately, because they lose viability when dried; keep them damp and cool, and sow two centimetres deep in a deep pot. Germination is in spring, and the seedling makes a taproot first, so use a deep container and avoid root disturbance. Grow it in light shade for the first year and full sun after that, in acid, humus-rich, well-drained soil. Plant out at forty to sixty centimetres, in a frost-free site with room for a twenty-metre tree, and water through the first two summers. It is slow for the first three years and then steady. Protect young trees from browsing, and do not expect nuts before the tree is fifteen or twenty years old.
Our Take
A big evergreen for frost-free ground, grown for the canopy and the spiny nuts rather than for quick effect. Give it acid soil, space and patience.
Related Reading
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