Perennial to 1 m, the rhizome commonly contorted; basal lvs oblong-ovate or triangular-ovate, rounded to a broadly winged petiole; raceme stout, 5-9 נ1-2 cm, floriferous to the base; otherwise much like no. 14 [Polygonum viviparum L.]; 2n=24, 48. Native of Eurasia, rarely escaped from cult. in our range. May-Aug
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.