Wild Yam

Dioscorea villosa

Physical Characteristics

Dioscorea villosa is a PERENNIAL CLIMBER growing to 3 m (9ft 10in). See above for USDA hardiness. It is hardy to UK zone 6. It is in flower from September to October. The species is dioecious (individual flowers are either male or female, but only one sex is to be found on any one plant so both male and female plants must be grown if seed is required).. The plant is not self-fertile. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers moist soil.

Distribution

Eastern N. America - New England to Minnesota and Ontario, south to Virginia and Texas.

Habitats

Woodland Garden Sunny Edge; Cultivated Beds;

Edible Uses

Edible Parts: Root Edible Uses: Tuber - cooked[177]. Some caution should be exercised with this plant. See 'Medicinal Uses' for more information.

Medicinal Uses

Antiinflammatory Antirheumatic Antispasmodic Cholagogue Contraceptive Diaphoretic Homeopathy Vasodilator Wild yam roots, and the roots of many other members of the genus, contains diosgenin[222]. This is widely used in modern medicine in order to manufacture progesterone and other steroid drugs. These are used as contraceptives and in the treatment of various disorders of the genitary organs as well as in a host of other diseases such as asthma and arthritis[222, 254]. The roots are anti-inflammatory, antispasmodic, cholagogue, diaphoretic and vasodilator[165, 238]. They are also a visceral relaxant[165]. This plant affords one of the best and fastest cures for bilious colic, it is especially helpful in treating the nausea of pregnant women[4] and has been used to ease the pain of childbirth[257]. It is also taken internally in the treatment of arthritis, irritable bowel syndrome, gastritis, gall bladder complaints, painful menstruation etc[238]. The root is harvested in the autumn and dried for later use[238]. The root should not be stored for longer than 1 year, since it is likely to lose its medicinal virtues[4]. Caution is advised in the use of the this plant, when taken fresh it can cause vomiting and other side effects[222]. The root, harvested in September, is used to make a homeopathic remedy[232]. Its main use is in the treatment of infant colic[232].

Known Hazards

Edible species of Dioscorea have opposite leaves whilst poisonous species have alternate leaves[174]. Use of the fresh plant can cause vomiting and other side effects[222]. Known to cause headaches, menstrual irregularities & acne. May cause hair loss & oily skin. Avoid during pregnancy. Avoid in patients with cancers of the breast, ovaries, prostate & uterus [301].