Fallopia convolvulus

Native of northern Africa, Europe, Asia, and the Indian subcontinent. Introduced and naturalized in North America.

Common

Cultivated grain fields, railroads, roadsides, disturbed areas. Full sun.

May to October

Greenish-white

Twining, 20″ to 40″ long

This is an annual vine that rises on a single stem from deep, fibrous roots. It does not produce rhizomes. It climbs by spiraling counter-clockwise (twining) around the stem of another plant.

The stems are trailing or twining, 20″ to 40″ long, light green or bright red, not woody (herbaceous), not glaucous, slightly angled, and freely branched at the base. They are somewhat rough to the touch due to the presence of short, stiff hairs that are often arranged in lines. The stems and leaves do not have a milk latex.

The leaves are alternate, widely spaced, ¾″ to 2⅜″ long, and ¾″ to 2″ wide. They are on 3 ⁄16″ to 2″ long leaf stalks. The leaf stalks are somewhat roughened with lines of short, stiff hairs. There is a small, hairless, membraneous sheath (ocrea) that surrounds the stem at the base of each leaf stalk. The leaf blade is heart-shaped or arrow-shaped with the basal lobes sometimes directed inwards, though this may not be apparent. It is sharply pointed at the tip with curved sides along the tip. The upper surface is hairless. The lower surface is usually powdery (mealy) and is not glaucous. The margins are untoothed and somewhat wavy.

The inflorescence is an unbranched, spike-like, ¾″ to 4″ long arrangement of several clusters of 3 to 6 flowers each at the end of the stems and branches and also rising from the leaf axils. The clusters are stalkless or on stalks up to 4″ long. The individual flowers are on 1 ⁄32″ to ⅛″ long stalks. The central axis of the inflorescence (rachis) is somewhat roughened with lines of short, stiff hairs.

Each flower is ⅛″ to 3 ⁄16″ long. There are 5 elliptic to inversely egg-shaped, petal-like sepals (tepals) and no petals. The tepals are greenish white and often have a pink or purple tinge at the base. The outer 3 tepals are slightly ridged (keeled).

The fruit is a dull black, 3-angled achene, enclosed within the 3 winged, persistent sepals.

Field bindweed (Convolvulus arvensis) is a longer vine, reaching up to 6½′ in length. The stems and leaves have a milky latex. The leaf stalk does not have an ocrea at the base. The flower is large, showy, and trumpet-shaped. The fruit is a capsule.

Hedge bindweed (Calystegia sepium ssp. angulata) is a longer vine, reaching up to 10′ in length. The stems and leaves have a milky latex. The leaf stalk does not have an ocrea at the base. The flower is large, showy, and trumpet-shaped. The fruit is a capsule.

Throughout

This species is found in every state, province, and territory in North America except Nunavut.