Slender, tufted perennial 3-9 dm; lvs mostly basal or below the middle of the stem, usually erect, the blade flat or more often involute, 1-2(-3) mm wide; ligule short, mostly 1-2.5 mm; infl ±flushed with reddish, ovoid or pyramidal, very diffuse, 1-3+ dm, sometimes half as long as the whole plant, the scabrous filiform branches finally divaricate, mostly forking well above the middle; spikelets 1.2-3.2 mm; glumes scabrous on the midvein; lemma awnless or with a short straight awn; callus short-bearded; palea obsolete or to 0.3 mm; anthers 0.3-0.6 mm; 2n=28, 42. Abundant, widely distributed in many habitats, and highly variable; Lab. to Alas., s. to Fla. and Mex. Two vars.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.