Climbing false buckwheat is a rampant annual or perennial climber often forming curtainlike masses of twining red stems, covering shrubs and trees. Flowers are 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.
Stem length: to more than 16 feet.
Scattered to common nearly statewide.
Habitat and Conservation
Occurs in moist, open or shaded bottomlands, alluvial valleys, and floodplains; also glades, banks of streams and rivers, edges of ponds, lakes, sloughs, and seeps, and ledges and tops of bluffs, crop fields, fencerows, ditches, quarries, railroads, roadsides, and other open, disturbed areas.
Status
Native nonwoody vine.
DNA research has been causing a reclassification among members of the smartweed family (Polygonaceae). The family is diverse, with many different forms (you probably know buckwheat and rhubarb). Also, it can be hard to tell one genus from another within the family. Plants in genus Fallopia used to be grouped with many more species as members of genus Polygonum (knotweeds). Exact identification usually requires examining the fruits (seeds), which are typically angled or winged in notable ways.
Human Connections
The flower and fruit clusters of this native plant are rather showy. Although you probably wouldn’t want to plant this rampant buckwheat in your yard, you should be glad for the shelter and food it provides for wildlife, and its contribution to stabilizing bottomland soils that are most prone to flooding.
Ecosystem Connections
Many bees, wasps, flies, butterflies, moths, and beetles visit the flowers. Other insects eat the foliage. The nutritious seeds are eaten by many species of birds, including upland game birds, and by seed-eating mammals. The dense thickets provide wildlife shelter.