yam

The rhizome of Dioscorea opposita is thick and straight, and the length can reach 1 meter. Leaves alternate, opposite to the middle or above, rare or 3 whorls, often with bulbils (Reiyoshi) between the axils, with varied leaf shapes, ranging from triangular ovoid to triangular broadly ovoid, often 3-lobed to deeply lobed. The flowers are dioecious, very small, green and white, all in spikes, the male inflorescence is erect, and the female inflorescence is below. Capsule has 3 wings. Perennial twining herbs; Having massive or rhizomatous underground stems; Leaves alternate, sparsely opposite, simple or palmately compound, divided or 0; Flowers dioecious; Rarely the same plant, forming spikes, racemes or panicles; Tepals 6, 2 whorls, connate at base; Stamens 6, sometimes 3 develop and 3 degenerate; Female flowers are similar to male flowers, but stamens are degenerated or absent; Ovary inferior, 8-loculed, style 3, separated; Capsule or berry; Seeds with wings. Growth habits like light, not cold tolerance is poor. It is suitable to grow in loam with good drainage and loose fertility. Avoid flooding. Underground yam stems are cylindrical, and may be deformed due to different growth geology, fleshy and hypertrophy. The first yam: the stem is cylindrical, the leaves are triangular-ovoid to triangular-ovoid, and the base is halberd-shaped. The male inflorescence is spike-shaped, not pendulous, the long axis is mostly zigzag, the male flowers are nearly sessile, the bracts are triangular-ovate, shorter than the perianth, the perianth segments are 6, ovate, and stamens are 6, developing; The female inflorescence is similar to the male inflorescence, and the ovary stigma is 3-lobed. Capsule has 3 wings, the fruit wings are several times as long as wide, with short stalks, and 2 seeds per room, which are placed in the center; The seeds are ovoid, surrounded by chestnut shell-colored thin wings, which are about 6 mm wide and unequal in width. The flowering period is from June to August, and the fruiting period is from August to October. The second kind of yam: asexual propagation, cylindrical stem, heart-shaped leaves, no flowers, "yam bean" between the axils, "yam bean" fell to the ground after withering in autumn and winter, and sprouted in the next spring.
Reprinted with attribution： https://cnlocality.com/(Chinese Specialty Products)