Culms 1-4 dm, scarcely tufted, without rhizomes; lvs mostly on short basal shoots, 3-5 cm נ1.5-4 mm; cauline lvs 1 or 2, erect, 1-5 cm נ2-3 mm; ligule (1-)2-4 mm; panicle long-pedunculate, pyramidal, 3-6 cm, nearly as wide, its branches mostly paired, soon divaricately spreading; spikelets 4.5-6(-7) mm, (3)4-6-fld; glumes ovate, over half as wide as long, herbaceous- margined, the first 2.4-3.9 mm, the second 2.6-4.5 mm; lemmas 2.9-4.5 mm, spreading-hairy on the lower half of the keel and marginal veins, and to some extent in the interveinal areas below, not webbed, the intermediate veins obscure; anthers 1.5-2.2 mm; 2n=14-74. Calcareous shores and ledges; circumboreal, s. to N.S., Que., the Bruce Peninsula of Ont., and Keweenaw Point, Mich. (P. اaspensis)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
