CHINESE YAM, CINNAMON VINE, AIR POTATO (Dioscorea batatas, D. oppositifolia, D. bulbifera)
Description
Chinese Yam and air potato are long-climbing vines with 2- to 3-inch wide shiny heart-shaped leaves having arc-shaped veins.
Leaves may vary in shape to arrowhead-like with lobes at the leaf base.
Pea- to marble-sized bulbils like small potatoes occur at leaf nodes in late summer. These may become potato-sized in other regions.
Ripe bulbils drop readily at slighest touch.
Origin--Asia
Distribution
Found increasingly in all counties at low to mid-elevations, along rights of way, forest edges, and in open spaces.
Threat
The vine is fast-growing (up to 1 inch/day at peak). It covers trees, shrubs, ground vegetation, and structures.
Reproduces prolifically starting in late June, and can spread rapidly along forest edges and openings.
Control
Shading not recommended for long-term control.
Mechanical control includes clipping, pulling, or burning plants before bulbils form in mid-June. Follow-on foliar herbicide control of sprouts with glyphosate.
Glyphosate foliar spray (Roundup) June to August as bulbils just forming.
Similar Plants
The native yam has similar leaves, but does not grow as aggressively. It often remains small and vertical (non-vine) and is found in shady forests.
Links to sites with additional information on Chinese Yam
The Nature Conservancy's Invasives on the Web--Chinese Yam
