Please try our next iteration of the Michigan Flora Online here. Beginning on February 1, 2023, will point to this new site.

The new site offers several benefits over the existing website, including real coordinate mapping, giving a clearer view of the density of documentation as well as more precision about plant distributions and their link to landforms. We will also have the ability to update species pages more regularly, both in terms of new collections and as more existing Michigan specimens are georeferenced. In addition, we have a better photo display, and offer indented keys.

Dioscorea villosa L.
Common Name: WILD YAM
Coefficient of Conservatism: 4
Coefficient of Wetness: 0
Wetness Index: FAC
Physiognomy: Nt P-Vine

Dioscorea villosa male flowers B. S. Walters male flowers

An herbaceous vine in rich dense or dry open forests, fencerows, and thickets; often along pond and marsh borders, river bottoms, and railroads.

Al-Shehbaz & Schubert (1989) consider D. villosa to be a primarily Coastal Plain species with strongly ridged stems and leaves all alternate, while recognizing our plant as D. quaternata J. F. Gmel., with essentially terete stems and the lowest leaves on the stem whorled. Many, however, regard this variation as part of a broadly defined D. villosa. Herbarium collections often do not have the lower portions of the stem, but our plants in the field may have the lowermost leaves alternate or whorled in the same population, and the stems seem slightly ridged. Hopefully further work will clarify this situation.


Allegan County
Barry County
Berrien County
Branch County
Calhoun County
Cass County
Clare County
Clinton County
Eaton County
Genesee County
Gratiot County
Hillsdale County
Ingham County
Ionia County
Jackson County
Kalamazoo County
Kent County
Lake County
Lapeer County
Lenawee County
Livingston County
Manistee County
Mason County
Mecosta County
Menominee County
Midland County
Monroe County
Muskegon County
Newaygo County
Oakland County
Ottawa County
Saginaw County
Shiawassee County
St. Clair County
St. Joseph County
Tuscola County
Van Buren County
Washtenaw County
Wayne County


MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. January 30, 2023.