Polygonum aviculare prostrate knotweed Polygonaceae POAV*; Bx, pb, sd, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct; Q, f, j, ri; R, c, is, js;

 

Polygonum aviculare Pihatatar.it.wikipedia.org

Polygonum aviculare Pihatatar.it.wikipedia.org (Accessed 3/2015).

Polygonum aviculare is a weedy taprooted annual herb to 10 (20) cm, freely branched, prostrate or sprawling to almost erect; nodes with membranous sheaths (ocreae) 0.4-0.8 cm, becoming tattered strips; node sheath membranous, becomng shredded. 

Leaves alternate, of several sizes, early leaves larger, 2.5-6 cm long, 0.4-1.5 cm wide, lance-shaped, later leaves and those of inflorescence about 1/3 as large, blade blue-green, jointed at base,. 

Polygonum aviculare.Arnoldo Mondadori.www.hear.org

Polygonum aviculare.Arnoldo Mondadori.www.hear.org (Accessed 4/2014).

Flowers green with white or pink margins, to 0.4 cm when mature, petal lobes longer than tube (corolla divided to below middle), tips flat, in axils; blooming and fruiting June-Nov. (Hough 1983). Fruit an achene, dark brown, to 0.3 cm, very finely warty. 

Wetland status: FACU . 

Frequency in NYC: Occasional. 

Origin: Eurasia 

Habitat: Open disturbed areas, abused lawns, ball fields, path edges, very tolerant of compaction, disturbance. 

Note: Usually not in natural areas.