Culms 15-50 cm, pilose. Leaves: sheaths pilose; ligules longer than wide; blades 1.5-3 mm wide, pilose. Inflorescences: lateral spikes approximate or proximal distant, 6-12 × 4-7 mm; terminal spike staminate or, rarely, gynecandrous with not more than 1/4 flowers pistillate, 8-16 × 2-4 mm. Pistillate scales ovate-circular, 2-3 × 1.6-2.5 mm, not more than 1.5 times as long as wide, shorter than perigynia, apex obtuse to acuminate. Staminate scales ovate, 3.2-4.1 mm, apex acute or acuminate. Anthers 1.9-2.4 mm. Perigynia ascending, strongly 18-24-veined, ovate or obovate, 2.2-3.2 × 1.5-2.2 mm, glabrous; beak 0.2-0.5(-1) mm. Achenes 2-2.5 × 1.5-1.9 mm. Fruiting summer. Meadows, moist woods; 200-2500 m; Alta., Man., Sask.; Colo., Minn., Mont., N.Dak., S.Dak., Wis., Wyo.
Much like no. 158 [Carex pallescens L.]; pistillate spikes 5-12 mm; pistillate scales subrotund, much shorter than the perigynia, minutely cuspidate, conspicuously hyaline-margined; perigynia obovoid, 2.5-3.5 mm, narrowed to the base, the body conspicuously 15-25-nerved, rounded to a cylindric beak 0.2-0.5 mm; 2n=58. Thickets and moist meadows, mainly on the n. Great Plains; Wis. and Minn. to Alta., Mont., and Colo.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.