Polygonum pensylvanicum L.

  • Authority

    Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

  • Family


  • Scientific Name

    Polygonum pensylvanicum L.

  • Description

    Species Description - Erect, branching annual to 2 m, or seldom prostrate; lvs lanceolate, acuminate; ocreae becoming lacerate, but not fringed-ciliate; racemes numerous, erect, commonly cylindric, blunt, 1.5–3 cm, ocreolae ovate, entire or minutely ciliate; perianth rose or white, scarcely exceeding the achene, 5-lobed to below the middle, the segments with several inconspicuous, branched and anastomosing veins; achenes lenticular, concave on both sides, 2.6–3.4 mm, 85–100% as wide; 2n=44. Fields and waste ground, especially in moist, rich soil; N.S. and Que. to Minn. and S.D., s. to Fla. and Tex. Highly variable, but scarcely divisible into significant vars. Heterostylic southern plants, reaching our range in s. Ill., have been segregated as P. bicorne Raf. (P. longistylum Small), but the populational relationship of these plants to the widespread, homostylic P. pensylvanicum remains to be elucidated.

  • Common Names

    Pennsylvania smartweed