Virginia Tech Weed Identification Guide

Cinnamon Vine, Chinese Yam or Potato Vine: Dioscorea batatas

potatovine8-3b.jpg (140999 bytes) Weed Description:   Herbaceous or slightly woody twining vines with fleshy or woody rootstocks, winding upward from left to right to approximately 13 feet in length.  Found especially throughout the piedmont and mountainous areas of the southeastern United States.
Leaves:  Alternate or lower leaves opposite and ovate with a long tapering point, concave sides, and heart-shaped base (cordate).  Leaves have 9 to 13 distinct veins.  Leaves are thin and without hairs (glabrous) or nearly so above, pubescent or sometimes glabrous beneath. Petioles often longer than the blades.  New leaves often have a bronze 'tint'. chineseyam9-10b.jpg (82059 bytes)
Stems:  Herbaceous or slightly woody vine that twines upward from left to right.
Flowers:  Greenish-yellow, nearly sessile, in spikes or panicles at the ends of branches, from June-August. potatovine6-26b.jpg (76110 bytes)
potatovine6-26.jpg (96907 bytes)  

Roots:  Slender or stout, simple or branched, horizontal and woody.

Fruit:  Membranous, 3-angled capsule, approximately 3/4 to 1 1/4 inches long and 3/4 inch in diameter.

Identifying Characteristics:  This weed is often confused with wild yam, however the vines of wild yam twine upwards from the right to the left, while those of cinnamon vine twine from the left to the right.  Cinnamon vine is also commonly confused with the morningglory species.  However, the distinct leaf veination and bronze 'tint' of newer leaves help to distinguish this weed from most morningglories. potatovine8-3.jpg (78286 bytes)