Chinese yam
Dioscorea polystachya Turcz.


Dioscorea polystachya is an invasive herbaceous, twining vine that grows to about 16.4 ft. (5 m). It invades open to shady areas in the Eastern United States.
The leaves are alternate proximally but can become opposite as they advance up the vine. They are about 8 in. (20.3 cm) long, wide, and heart to fiddle shaped (margins three-lobed), with prominent, parallel veins. The petiole base is not clasping. Leaves are usually more rounded when young or on young plants and fiddle shaped farther along the stem and on older plants. The rounded stems are thin and wiry.
The staminate plants may produce small, white flowers annually.
The seeds are winged all around, but the chief means of reproduction are aerial, potato-like tubers (bulbils) located at the leaf axils and underground tubers.
Ecological Threat
Dioscorea polystachya can form dense masses of vines that cover and kill native vegetation, including trees, within a variety of moist, disturbed habitats. It was introduced from Asia for ornamental, food, and medicinal purposes and escaped cultivation in the mid-1990s.

Selected Images


EDDMapS Distribution

EDDMapS Distribution - This map is incomplete and is based only on current site and county level reports made by experts, herbaria, and literature. For more information, visit

State Regulated List

State Regulated List - This map identifies those states that list this species on their regulated list. For more information, visit

Taxonomic Rank

Kingdom: Plantae
Phylum: Magnoliophyta
Class: Liliopsida
Order: Dioscoreales
Family: Dioscoreaceae
Genus: Dioscorea
Subject: Dioscorea polystachya Turcz.

Synonyms and Other Names

Related Scientific Names:
Dioscorea batatas L. (Synonym)
Dioscorea oppositifolia L. (Synonym)


Plants - Vines


Common Name Reference:

Scientific Name Reference: Flora of North America.