winged yam: Dioscorea alata (Dioscoreales: Dioscoreaceae)

winged yam	USDA PLANTS Symbol: DIAL2 USDA ARS GRIN: 14175 ITIS: 43372
Dioscorea alata L.
Taxonomic Rank: Liliopsida: Dioscoreales: Dioscoreaceae
Synonym(s): water yam
Winged yam is an herbaceous, twining vine that can grow to lengths exceeding 30 ft. (9.1 m). It invades open to shady areas in the extreme southeastern United States. Leaves are opposite, 8 in. (20.3 cm) long and narrowly heart-shaped with long petioles. The stems are square with the corners compressed into wings. The chief means of reproduction is by aerial potato-like tubers (bulbils) located at the leaf axils and by underground tubers. The vine rarely flowers. Winged yam can form dense masses of vines that cover and kill native vegetation including trees. It was introduced from Asia as a possible food source in the early 1800s. In some countries it is presently being cultivated for medicinal uses.

Identification, Biology, Control and Management Resources

Selected Images from Invasive.org

Foliage; leaves Forest & Kim Starr, U.S. Geological Survey, Bugwood.org Additional Resolutions & Image Usage	Foliage; leaves Forest & Kim Starr, U.S. Geological Survey, Bugwood.org Additional Resolutions & Image Usage	Foliage; leaves Forest & Kim Starr, U.S. Geological Survey, Bugwood.org Additional Resolutions & Image Usage	Plant(s); in August Fred Nation, Weeks Bay National Estuarine Research Reserve, Bugwood.org Additional Resolutions & Image Usage
Flower(s); Forest & Kim Starr, U.S. Geological Survey, Bugwood.org Additional Resolutions & Image Usage	Flower(s); habit Forest & Kim Starr, U.S. Geological Survey, Bugwood.org Additional Resolutions & Image Usage	Feature(s); Aerial tubers (bubils) Chris Evans, River to River CWMA, Bugwood.org Additional Resolutions & Image Usage	Fruit(s); yamlet Forest & Kim Starr, U.S. Geological Survey, Bugwood.org Additional Resolutions & Image Usage
Infestation; Chris Evans, River to River CWMA, Bugwood.org Additional Resolutions & Image Usage	Plant(s); habit Forest & Kim Starr, U.S. Geological Survey, Bugwood.org Additional Resolutions & Image Usage	Infestation; Chris Evans, River to River CWMA, Bugwood.org Additional Resolutions & Image Usage	Infestation; Chris Evans, River to River CWMA, Bugwood.org Additional Resolutions & Image Usage