Fallopia convolvulus, the black-bindweed or wild buckwheat, is a fast-growing annual flowering plant in the family Polygonaceae native throughout Europe, Asia and northern Africa.
Synonyms include Polygonum convolvulus L. (basionym), Bilderdykia convolvulus (L.) Dumort, Fagopyrum convolvulus (L.) H.Gross, Fagopyrum carinatum Moench, Helxine convolvulus (L.) Raf., Reynoutria convolvulus (L.) Shinners, and Tiniaria convolvulus (L.) Webb & Moq. The flowers have 5 sepals, the 3 outer ones are larger and show a keel. It has 5 stamens and the fruit grows to 4 mm long.
While it superficially resemble bindweeds in the genus Convolvulus there are many notable differences; it has ocrea (stipule-sheath at nodes), which Convolvulus does not; and Convolvulus has conspicuous trumpet-shaped flowers while Black-bindweed has flowers that are unobtrusive and only about 4 mm long.