Wild buckwheat (Black bindweed)

Fallopia convolvulus

Plant family: Polygonaceae (knotweed family)

Life cycle: Annua

Reproduction: Seed

Leaves: Leaves are alternate, almost heart-shaped and pointed at the apex. The leaf base has deep and rounded to pointed lobes. At the base of each leaf, a cylindrical, membranous sheath (ocrea) surrounds the stem. Leaves are can be up to 3.5 inches long.

Roots: Fibrous root system. Regeneration does not occur from roots.

Flowers: Individual flowers are small and inconspicuous (less than 0.5 inches in length). There are no petals, only sepals that are white to pink to green in color. Flowers are held in small clusters in leaf axils or at the end of stems.

Seeds: Seed are 3-angled and short-lived.

Fast-growing annual

Wild buckwheat, also known as black bindweed, is a fast-growing annual vine with fragile stems in the Polygonaceae (knotweed/smartweed family). The root system of wild buckwheat is composed solely of fibrous roots. Unlike the perennial bindweeds, reproduction does not occur from root fragments.

wild buckwheat stems and foliage — Wild buckwheat (also known as black bindweed), leaves, stems and flowers.

Image above: Wild buckwheat (also known as black bindweed), leaves, stems and flowers.

Seedlings emerge in spring/early summer. Cotyledons are long and oval. Leaves are alternate, almost heart-shaped and pointed at the apex. The leaf base has deep and rounded to pointed lobes. At the base of each leaf, a cylindrical, membranous ocrea surrounds the stem. Leaves are can be up to 3.5 inches long. Vines are branched at the base; internodes are long.

wild buckwheat leaves — Wild buckwheat/black bindweed leaves.

Field bindweed and wildbuckwheat leaves — Field bindweed leaf (left) vs. wild buckwheat leaf (right).

Image above: Wild buckwheat/black bindweed leaves (left). Field bindweed vs. wild buckwheat/black bindweed leaves (right).

Flowers are produced from mid-summer through fall. Individual flowers are small and inconspicuous (less than 0.5 inches in length), unlike those of field and hedge bindweed. There are no petals (just sepals that are white to pink to green in color). Flowers are held in small clusters in the axils of the leaves or at the end of stems (racemes). There are no bracts present below the flowers.

Wild buckwheat produces triangular (3-angled) seed that are short-lived. Unlike field and hedge bindweed seed, which may last for decades in the soil, black bindweed seed only persist a few years.

Images above: Wild buckwheat flowers (left). Right image shows wild buckwheat (left) versus field bindweed (right).