The scientific name of wild yam is Dioscorea villosa. Wild yam is very frequently confused with sweet potato, but there is a lot of difference between the two. The wild yam plant is also called colic root. There are two species of wild yam, one from North America and the other is from China. The wild yam plant is like a bush and has a cluster of small, yellowish green or whitish green flowers. Many of its species are found in damp thickets and woodlands. It has knotty roots, which are pale brown and are cylindrical shaped. Their roots can grow up to 30 feet in length. The taste of the wild yam roots is starchy to bitter and acrid.