Morphology
A rhizomatous, perennial grass with culms 50-150(200) cm tall and 8-12 mm thick. Sheaths keeled. Ligules 1-5(7) mm. Blades 25-43 cm long, 4.5-15 mm wide.
Panicles16-42 cm long, 12-20 cm wide. Branches (7)10-18 cm long. Spikelets 3.2-10 mm long, 2-3 mm wide, somewhat laterally compressed, with 4-10 florets. Lower glumes 1-2.3 mm. Upper glumes 1.5-2.7 mm. Lemmas 1.8-3 mm, (5)7-veined. Anthers 3, 0.5-1.2 mm.
Name/Synonymy Info
Glyceria grandis S. Watson in A. Gray, Manual, ed. 6, rev. S. Watson & J.M. Coulter, 667 (1890). LEC: GH 24593; Canada, Québec; 1858; Munro [Hitchc., Man. Grasses U.S. 865 (1935)].
Glyceria grandis S. Watson var. grandis in A. Gray, Manual, ed. 6, rev. S. Watson & J.M. Coulter, 667 (1890). Panicularia grandis (S. Watson) Nash in Britton & A. Br., Ill. fl. n. U.S., ed. 2, 1:265 (1913); Glyceria maxima subsp. grandis (S. Watson) Hultén, Acta Univ. Lund, n.s., 38:229 (1942); Glyceria maxima var. grandis (S. Watson) Breitung, Canad. Field-Naturalist 71:45 (1957). LEC: GH; Canada, Québec; 1858; Munro [Hitchc., Man. Grasses U.S. 865 (1935)].
Poa aquatica var. americana Torrey, Fl. n. middle United States 1:108 (1823); Panicularia americana (Torrey) MacMillan, Metasp. Minnesota valley 81 (1892); Glyceria americana (Torrey) Pammel in Pammel, C.R. Ball & Scribner, Grasses Iowa 2:271 (1905) [title page 1904]; Glyceria maxima var. americana (Torrey) B. Boivin, Naturaliste Canad. 94:524 (1967). TYPE: U.S.A., Massachusetts: Deerfield; G.E. Cooley.
Glyceria flavescens M.E. Jones, Bull. Montana State Univ., Biol. Ser. 15:17, pl. 2 (1910). TYPE: U.S.A., Montana: Swan Lake; 24 Aug 1908; M.E. Jones [9697].
Glyceria grandis var. komarovii Kelso, Rhodora 36:266 (1934). Glyceria hultenianum Á. Löve, Svensk Bot. Tidskr. 48:218 (1954). HOL: US 948398; Canada, Yukon Territory: Dawson City; 17-19 Jul 1909; A.S. Hitchcock 4362.
References
M.E. Barkworth & L.K. Anderton. 2007. Glyceria in Flora of North America, volume 24. Oxford University Press.
