The leaves of Dioscorea opposita generally vary greatly, ranging in shape from triangle to wide ellipse, and some even show halberd shape. As a single leaf, the lower part of the stem often alternate, the middle part is opposite to the upper part, and there are also three petals, but few. The leaves are 3-9 cm long and 2-7 cm wide. The top is pointed, and the bottom is deep and wide. The margin is 3-lobed, the middle lobe is elliptic or lanceolate, and the lateral lobes are auriculate. : The stems of Chinese yam are divided into aboveground stems and underground stems. The aboveground stems are purplish red, usually right-handed, and the surface is hairless. Underground stems are tubers, long cylindrical, usually grow vertically, and the length can reach 1 m. There are a large number of adventitious roots on the surface of tuber, some of which will grow taproots at the lower part, with terminal buds at the root neck and adventitious buds elsewhere.

Second, the rhizome shape

Dioscorea opposita is dioecious The male inflorescence is spike-shaped, 2-8 cm long. It is usually upright, of which 2-8 grow from the axils of leaves and occasionally arrange in a conical shape. Its inflorescence axis is zigzag with purple-brown spots on bracts and petals. The outer petals of male flowers are broadly ovoid with 6 stamens. The female inflorescence is also spike-shaped, with 1-3 bearings between leaf axils. Its fruit is a capsule, oblate or round, less than 2 cm long, with white powder on the surface.

Third, the shape of flowers and fruits