Castanea mollissima, or the Chinese chestnut, is a medium-sized deciduous tree belonging to the Fagaceae. It has an open, rounded crown and typically reaches heights of up to 25m tall. The furrowed bark is grey to light-brown in colour. Its pinnately-veined leaves are simple and elliptic-oblong to oblong-lanceolate. They also have coarsely-serrated margins. The name mollissima means “soft” in Latin, and is in reference to the fuzzy leaf undersides and downy twigs (above, the leaves are shiny and dark green). In autumn, the foliage changes to various shades of yellow, gold and copper.
Chinese chestnut trees produce showy cream-coloured catkins in early summer. The blossoms are either staminate or pistillate, with the male flowers being borne in the showy catkins and the female flowers in aments at the bases of the catkins. The catkins are typically 10 to 20cm in length, while the aments are much shorter, at 1.3 to 1.9cm long. Castanea mollissima plants are generally self-sterile and insect-pollinated.
The formidably spiny cupules can be found underfoot from late summer to autumn, when they litter the ground like tiny green porcupines. These dehiscent fruit cases hold two to three glossy edible nuts, with each nut being 2.5 to 3cm in diameter and flattened on one or two sides. Chestnuts are said to taste astringent when raw, but, after roasting, are sweet with a floury texture.
Castanea mollissima is native to China, Taiwan, and Korea. The species can be found growing in forests and on some mountain slopes up to 2800m above sea level. In Asia, Castanea mollissima is cultivated for its edible nuts; cultivars developed for nut production include ‘Abundance’, ‘Meiling’, ‘Nanking’, and ‘Kuling’. Each tree can yield 25-60 kilograms of chestnuts in a harvest season. North American chestnut growers have begun cultivating hybrids of Castanea mollissima as an alternative to the American chestnut (Castanea dentata), as Chinese chestnut trees are much more resistant to chestnut blight (Cryphonectria parasitica). Castanea mollissima is also resistant to honey fungus (Armillaria spp.).