Prostrate knotweed – Polygonum aviculare

Prostrate knotweed

Polygonum aviculare L.
Polygonaceae (Smartweed family)

Life cycle

Prostrate, mat-forming summer annual.


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


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.

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 plant
Prostrate knotweed flower
Prostrate knotweed seedling
Prostrate knotweed ocrea

For more information visit:

Plant & Pest Diagnostics

Other Documents in this Series

Accessibility Questions:

For questions about accessibility and/or if you need additional accommodations for a specific document, please send an email to ANR Communications & Marketing at

Michigan State University Michigan State University Close Menu button Menu and Search button Open Close