Overall At-Risk Score: 41
Synonyms: D. glauca, D. hirticaulis, D. quaternata
Dioscoreaceae (Yam family)
D. villosa is a dioecious plant, meaning each plant has a distinct sex. On male plants, tiny, pale green flowers develop in tight clusters along the vine. The female flowers are larger, tubular blossoms of similar color. The fruit develops into a three-part capsule, with each cell containing a two-winged seed for wind dispersal.
Wild Yam has a large native range encompassing most of the eastern United States, ending at the edge of the Great Plains. It is specifically found in the states of Alabama, Arkansas, Connecticut, Delaware, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maryland, Michigan, Minnesota, Mississippi, Missouri, Nebraska, New Jersey, New York, North Carolina, Ohio, Oklahoma, Pennsylvania, Rhode Island, South Carolina, Tennessee, Texas, Vermont, Virginia, West Virginia, and Wisconsin. It is also found in southern portions of the Canadian province Ontario.
Wild yams prefer partial to full sun and grow well in sandy soil. They grow primarily in savannahs and woodland borders but can also commonly be found in unkempt developed areas like fence lines, railroad clearings, and powerline clearances.
Ability to Withstand Disturbance and Overharvest:
As the root system is the part most commonly wild-harvested, it is common for the entire plant to be dug up, putting it at generally more at risk of a disturbance than plants that only have their leaves harvested.
Status of Endangered/Threatened (by state):
No legal protections for Dioscorea villosa exist.
Dioscorea villosa has not yet been evaluated by the IUCN Red List.
Part of Plant Used/Active Medicinal Compounds:
Wild yams have been used historically by the Meskwaki primarily to soothe labor pains; however, there are records of physicians using the root in an attempt to cure various respiratory issues, as well as rheumatism and morning sickness.
This plant contains diosgenin compounds that are used to produce a variety of modern steroid drugs, as well as hormone-related drugs used as contraceptives and to treat menopause and PMS.
Recommendations for industrial and home use:
There is a very limited market for farmed D. villosa, meaning that almost all of the product on the market is gathered in the wild. This increasing market can put a serious strain on established populations and prevent new colonies from establishing.
This plant is very easy to grow at home and will thrive in often underused edge and transitional habitats. Please talk to your doctor before attempting to take Dioscorea villosa or any other medicinal plant.
- Duke, J. and Foster, S., (1990), A Field Guide to Medicinal Plants and Herbs: Eastern and Central North America, Boston MA, Houghton Mifflin, Page 204.
- Integrated Taxonomic Information System. (n.d.). ITIS Standard Report Page: Ligusticum porteri. Retrieved from https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=43367#null
- Smith, Huron H., 1928, Ethnobotany of the Meskwaki Indians, Bulletin of the Public Museum of the City of Milwaukee 4:175-326, page 220.
- USDA, (n.d.), Plants Profile for Dioscorea villosa (wild yam), Retrieved August 18, 2019, from https://plants.usda.gov/core/profile?symbol=DIVI4