Prostrate Knotweed, Polygonum aviculare
Family: Polygonaceae; Buckwheat Family
Vegetative Characteristics:
Seedling: cotyledons small, linear; stem reddish; leaves blue-green, glabrous
Stems: prostrate, to 1.0 m long, highly branched, conspicuous nodes, glabrous
Leaves: alternate, 5.0-30.0 mm long, 1.0-8.0 mm wide, simple, linear, margins entire, blue-green; petiole short; ocrea fringeless and veinless
Reproductive Characteristics:
Inflorescences: axillary clusters, small, perfect, included in or barely exserted from leaf axil; sepals green with white or pinkish margins, 1.0-1.6 mm long
Fruits: achene, 2.0-25.0 mm long, ovoid, reddish brown to dark brown, lustrous; calyx adhering to achene, green with pink or white margins
Special Identifying Features:
⇒ Prostrate to loosely ascending annual; flowers in leaf axil, inconspicuous; ocrea lacking fringe and veins
