Prostrate Knotweed (Polygonum aviculare L.)

Alien: Native of Europe.

Identification: Plant prostrate and straggling across the ground. Flowers small, pale green or white with pink tips and located in groups of 1 to 5 in the flower axils. Junction of leaf and stem swollen with a papery silver sheath rapidly becoming tattered and torn. Stem striate and much branched. Leaves blue-green, elongate-ovate, without petioles.

Distribution: Throughout North America.

Habitat: Found in a variety of disturbed habitats including empty lots, fields, roadsides, and sidewalks.

Flowering period: June to November.

Similar Species: Other similar species of Knotweeds such as Erect Knotweed and Bushy Knotweed are erect, not straggling and trailing along the ground. The blue-green color of the leaves is distinctive.