Potamogeton gramineus 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

    Potamogeton gramineus L.

  • Description

    Species Description - Stems slender, somewhat compressed, much branched, 3–7 dm; submersed lvs sessile, linear or lance-linear to oblanceolate, 3–8 cm × 3–10 mm, acute to cuspidate, 3–7-veined; floating lvs narrowly to broadly elliptic, 2–5 cm, a fourth to half as wide, 11–19-nerved, obtuse to rounded or subcordate at base, the slender petiole often exceeding the blade; stipules axillary, free, 1–3 cm, obtuse; peduncles 2–4(–15) cm, thicker than the stem; spikes dense, cylindric, 1.5–3 cm; frs obovoid, 2–2.5 mm, the sharp dorsal keel and the obscure lateral ones developed chiefly beyond the middle, the sides shallowly pitted; 2n=52. A highly variable circumboreal sp., in Amer. extending s. to N.Y., Io., and Calif. (P. heterophyllus, misapplied) Putative hybrids with various other spp. have been called P. ×hagstroemii A. Benn., P. ×spathulaeformis Morong, P. ×subnitens Hagstr., and P. ×varians Morong)

  • Common Names

    variable pondweed