Carya cathayensis aka Cathay Hickory

Carya cathayensis, or Chinese hickory, is a deciduous tree. It belongs to the walnut family, Juglandaceae. Its native range lies in China, from southern Guizhou to Zhejiang. It grows in a temperate climate. Wild trees occur in moist, narrow valleys and at mountain bases. They also grow on wooded slopes and beside rivers. Recorded sites lie at 1,312–4,921 feet [400–1,500 metres] above sea level.

This slow-growing tree reaches about 59 feet [18 metres] tall. PFAF records its leafy season as June through October. Its strong taproot affects how growers should raise young plants. Deep pots give the root room to grow. Young trees need planting in their final site early. PFAF suggests doing this during their first summer where possible. The tree can form part of a woodland garden canopy. It also has a place in food forests.

Flowers appear from April to May, and wind carries their pollen. Each tree bears separate male and female flowers. The species is self-fertile. Seeds ripen from September to October. Their sweet kernels contain much oil and have food value. People eat them raw or cooked and extract cooking oil. Growers cultivate the tree for food in China. Local markets also sell its seeds. Seeds kept cool in their shells can last at least six months.

Choose a sunny site with shelter from wind. The tree cannot grow in shade and dislikes exposed sites. It prefers deep loam that holds moisture. It can also grow in sandy or clay soils. Suitable soil reactions range from mildly acid to mildly alkaline. A good summer helps the tree develop well. PFAF lists USDA zones 5–9, but its frost reports conflict. One account warns of frost damage; another suggests tolerance of 5 to −4°F [−15 to −20°C]. Young plants need cold protection for at least their first winter.

Seed propagation requires a cold period before germination. PFAF advises sowing ripe seed in a cold frame. Stored seed should stay moist rather than wet before sowing. Beyond food, the tree supplies hard, tough, flexible wood. People use this wood for tool handles and fuel. It burns well and gives strong heat. PFAF lists no known hazards or medicinal uses. This does not establish safety for every person or animal.