Densely tufted, 3-7 dm; ligules 2.5-7.5 mm, acuminate, becoming lacerate; blades numerous, smooth, strongly involute, ca 1 mm wide, nearly as long as the stems; panicle (5-)7-15(-19) cm, open, diffusely branched, with long-pedicellate spikelets; glumes ovate-acuminate or tapering to an awn to 2 mm, hyaline-margined, finely puberulent to subglabrous, the 3(5) nerves prominent toward the greenish glume-base, obscure in the anthocyanic distal part; first glume (4.5-)5-7.5(-8) mm, the second a bit shorter; lemma 2.5-4(-5), fusiform, turgid, maturing dark and shiny, densely white-pilose with long soft hairs ca = glumes; awn 3-5.5 mm, straight, readily deciduous; 2n=28, 48, 65, 130. Dry, open often very sandy places; Man. and nw. Minn. to B.C., s. to Calif. and Tex. (Achnatherum h.) Hybridizes with several spp. of Stipa, producing sterile plants
called Ř“tiporyzopsis bloomeri (Bol.) B. L. Johnson.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.