Culms 6.8-40 cm. Leaves: basal sheaths pale to medium brown; blades dull green to yellowish green, exceeding culms, 1.5-5.9 mm wide, widest ones 2-5.5 mm wide, herbaceous, margins green, papillose. Lateral spikes 0-3, basal, on erect peduncles. Terminal spikes with staminate portion 2-3-flowered, 1.7-2.6 × 0.4-0.9 mm; pistillate portion 3-5-flowered. Pistillate scales yellowish green to dull olive green, margins green, 2.5-3 mm wide, essentially concealing perigynia, apex acute; distal scales ovate, apex acute. Staminate scales white or green, often with reddish brown tinge, margins connate, sometimes for entire length, enfolding scales above, apex obtuse. Anthers 0.9-1.4 mm. Perigynia yellowish green to dull olive green, obovoid, 3.9-5.4 × 1.6-2.5 mm, tightly enveloping achenes, apex abruptly tapered; beak 0.5-1.6 mm, smooth. Stigmas clavate, erect, minutely papillose. Achenes brown, obpyriform, 2.8-3.5 × 1.5-2.4 mm.

Fruiting spring-summer (late May-late Jul). Naturally disturbed, rocky slopes with organic layer and leaf litter in mesic mixed forests, or disturbed, open, grassy slopes; 500-2400 m; Alta., B.C.; Idaho, Mont., Oreg., Utah, Wash., Wyo.