Polygonum viviparum L.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Erect perennial 1–4 dm from a short, stout rhizome, the stem simple and few-lvd; lowest lvs linear-oblong, 3–8 × 0.5–1.5 cm, long-petioled, the others progressively reduced and nearly linear; raceme 1, slender, 3–6 × 0.5–1 cm, the lower fls usually replaced by bulblets; pedicels jointed at the summit; tep white or pink, obtuse, the inner the wider; stamens long-exserted; styles 3, longer than the ovary; achene trigonous; 2n=66–132. Moist, usually calcareous soil; circumboreal, s. in our range to n. Minn., n. Mich., and the higher mts. of N.E. Late June–Aug. (Bistorta v.)