Prostrate knotweed

Polygonum aviculare L.

Life cycle

Prostrate, mat-forming summer annual.

prostrate knotweed plant
Prostrate knotweed plant.

Leaves

Alternate, narrow oval to oblong leaves with pointed tips, smooth margins and short petioles.

prostrate knotweed seedling
Prostrate knotweed seedling

Stems

Prostrate, tough, wiry stems with distinct nodes are highly branched and mat-forming. Plants perform well in compacted areas. A membranous sheath (ocrea) surrounds the stem at the base of each petiole.

prostrate knotweed ocrea
Prostrate knotweed ocrea.

Flowers and fruit

Small, inconspicuous flowers are white to pinkish and clustered in the leaf axils. The seed is enclosed in a single-seeded, dark reddish brown, three-sided fruit.

prostrate knotweed flower
Prostrate knotweed leaf and flower.

Reproduction

Seeds.

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