Dioscorea villosa Identity & Plant Part
The botanical entity is Dioscorea villosa L., the wild yam or colic root, a slender climbing vine of the Dioscoreaceae native to eastern North America. The part used is the root, in practice the knotty rhizome. Vines, leaves and fruit are not part of this ingredient. The species is wild-growing, and its root is hard, woody and pale inside.
Wild yam is a different plant from the food yams grown in tropical agriculture, such as Dioscorea alata, and also from the sweet potato, which is not a yam at all. The root carries steroidal saponins such as dioscin, which can release diosgenin on hydrolysis, along with starch, named here as families only.












