Sphenopholis obtusata
Culms (9)20-130 cm. Sheaths glabrous or hairy, sometimes scabridulous; ligules (1)1.5-2.5 mm, erose-ciliate, more or less lacerate; blades 5-14 cm long, (1)2-8 mm wide, usually flat, rarely slightly involute, scabrous or pubescent. Panicles (2)5-15(25) cm long, 0.5-2 cm wide, usually erect, often spikelike, spikelets usually densely arranged. Spikelets 2.2-3.6 mm. Lower glumes less than 1/3 as wide as the upper glumes; upper glumes 1.5-2.5 mm, subcucullate, width/length ratio 0.3-0.5, apices rounded to truncate; lowest lemmas 1.9-2.8 mm, usually scabridulous distally; distal lemmas usually smooth on the sides, occasionally scabrous, unawned; anthers 0.2-1 mm. 2n = 14.
Distribution
Conn., N.J., N.Y., Wash., Del., D.C, Wis., W.Va., Pacific Islands (Hawaii), Mass., Maine, N.H., R.I., Vt., Fla., Wyo., N.Mex., Tex., La., Tenn., N.C., S.C., Pa., Nev., Va., Colo., Miss., Calif., Ala., Kans., N.Dak., Nebr., Okla., S.Dak., Ark., Ill., Ga., Ind., Iowa, Ariz., Idaho, Md., Ohio, Utah, Mo., Minn., Mich., Mont., Alta., B.C., Man., N.B., Ont., Sask., Ky., Oreg.
Discussion
Sphenopholis obtusata grows in prairies, marshes, dunes, forests, and waste places, at 0-2500 m. Its range extends from British Columbia to New Brunswick, through most of the United States, to southern Mexico and the Caribbean. The distal lemmas of S. obtusata are occasionally somewhat scabrous. Such plants can be distinguished from S. nitida (p. 621) by their narrower lower glumes, from S. filiformis (p. 621) by their wider leaves, and from S. pensylvanica (p. 621) by their shorter, unawned spikelets. Hybrids with S. pensylvanica, called Sphenopholis xpallens, have short (0.1-4 mm) awns on the distal lemmas.
Selected References
None.