Wild Yam

General Description

Wild yam is a perennial twining vine with a smooth, reddish-brown stem. The glabrous leaves are broadly cordate, from 2-6 inches long and 1-4 inches wide. Leaves are usually alternate, though lower leaves at times grow in whorls. Greenish-yellow flowers appear in late July and August, with male flowers in panicles and female flowers in racemes. Fruit is a 3-winged capsule containing seeds. Roots are long, crooked, and laterally branched (Foster and Duke 2000, Grieve 1931, Haughton 2001).

Natural Habitat

The native range of wild yam covers eastern North America from Ontario south to Florida and west to Minnesota and Texas (USDA, NRCS 2001). It is most commonly found in wet wooded areas and swamps, along thickets, fences, and hedges (Nutriflip 1998).

Uses

The rhizome and root are collected in autumn and dried for later use. The dried roots can be stored for up to 1 year. The roots contain saponin and a substance incorrectly called dioscorein, which can be precipitated with water in a laboratory (but not in the human body) to create progesterone. Wild yam is an anti-inflammatory, diuretic, and antispasmotic. It is most widely used to treat bilious colic, labor pains, nausea during pregnancy, menstrual cramps, spasmodic hiccough or asthma, and flatulence. Since it can cause vomiting, the root is never taken internally while fresh (Foster and Duke 2000, Grieve 1931, Haughton 2001, Jackson and Shelton 1997, Nutriflip 1998).

Status

Wild yam is listed as at risk by United Plant Savers and should not be harvested from natural habitat (United Plant Savers).

Silviculture

Plants can be propagated by baby tubers found in the leaf axils in late summer and early fall. They should be planted in pots and kept indoors until spring. (Jackson and Shelton 1997).

Grows best in partial shade, with medium, well-drained, moist soil (Jackson and Shelton 1997).

References

• Additional NTFP References
• Garden Web Glossary of Botanical Terms
• Dictionary of Medical Terms