Densely tufted perennial 1-5 dm; lvs mostly crowded at the base, the blades flat or more often involute, 1-3 mm wide; ligules mostly truncate and 1-2 mm; infl pyramidal, 5-15 cm, nearly as thick at base when fully expanded, the branches glabrous or nearly so, forking near the middle; spikelets purplish, 2-4 mm; first glume often scabrous along the midvein, the second usually glabrous; lemma 1.6-2.8 mm, bearing at or near the middle a bent awn 3-6 mm; callus very shortly bearded; palea short, to 0.5 mm; anthers 0.5-0.7 mm; 2n=56. Peaty or rocky soil; circumboreal, s. to Que. and on the higher mts. of Me., N.H., Vt., N.Y., W.Va., and in the w. cordillera. (A. borealis)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.