A rampant annual or perennial climber often forming curtainlike masses of twining red stems, covering shrubs and trees. Flowers minute, produced in masses on long racemes so that the effect is showy. Flowers are greenish white, sometimes pink-tinged, with a 5-parted calyx whose outer 3 segments are strongly winged, increasing the showiness. Blooms July–November. Leaves ovate to heart-shaped, to 6 inches long. Fruit enclosed in the enlarged remains of the winged calyx; a shiny, smooth, dark brown to black seed, which looks and tastes like buckwheat.
Similar species: Missouri has 4 species of Fallopia. Black bindweed (F. convolvulus) is found in similar habitats statewide. It has black fruits with a dull surface, finely roughened or with dense, small tubercles. Japanese knotweed (F. japonica), scattered mostly in eastern Missouri, is an invasive exotic that spreads aggressively, forming dense thickets. Also, the genus Polygonum is closely related.