Plants cespitose, with knotty, shortly rhizomatous bases. Culms 20-80 cm; nodes often with soft, 1-2 mm hairs. Sheaths rounded, lower sheaths often strigose or pilose, upper sheaths glabrous or scabrous; ligules 0.5-1 mm, membranous, ciliate; blades 1-4 mm wide, usually involute or loosely infolded, glabrous, scabrous, or sparsely pilose, attenuate distally. Panicles 7-20(25) cm long, 0.3-0.8 cm wide; branches erect, spikelets imbricate but usually not crowded; pedicels 1-2 mm. Spikelets 8-13 mm, with 5-11 florets. Glumes glabrous, usually purple-tinged; lower glumes 3-8(10) mm, 1-3-veined; upper glumes 4-10 mm, 1-7-veined; lemmas 3.5-7 mm, usually purple-tinged, midveins pilose on the basal 1/3 - 1/2, rarely excurrent, lateral veins pilose to well above midlength, never excurrent; paleas 1-2 mm shorter than the lemmas, margins pubescent; anthers 1-1.5 mm. Caryopses 1.5-2.3 mm. 2n = 40.
Kans., Okla., Colo., N.Mex., Tex., La., Utah, Calif., Ark., Ariz., Mo., Nev.