This is a natural medicine, that belongs to the family of true yam. (Dioscorea)
This crops is a native to the following: Asia continent, Africa continent and northern part of Australia, this means that, you can easily find it in those mentioned continent and country, their used for this crops is of greater heights.
For more details see Wikipedia
Upon it smaller size in nature, if you peel the body of this crop, it is green in color and has a very light shell covering the body.
Dioscorea bulbifera is a species of true yam in the yam family. It is planted the same way that others yam in the family are planted, it is supportive also, such that it has to grow on wood or stick, but the only difference with others yam in the family is that, it bears it tubers on the wood or support stick while, others yam bears their fruit on the ground.
Dioscorea bulbifera is widely cultivated now in many countries as it economic importance is reveal and has become naturalized in many regions, they are tiny in nature than all the rest of yam.
Such that you can carry more than three tubers at a time, I can remember when my grandmother used to cook it for us to eat, whenever she wanted to prepared it I always feels happy.