Culms trigonous in cross section, 40-80 cm. Leaves: basal sheaths reddish purple, inner bands slightly fibrillose with age; sheaths pubescent, at least at apex of inner band; ligules 2-9 mm; blades 2.5-6 mm wide, finely spreading-pubescent or glabrous, not papillose abaxially. Inflorescences 15-50 cm; spikes erect or ascending; proximal (1-)2-3 spikes pistillate; terminal 1-4 spikes staminate. Pistillate scales narrowly ovate, apex acute to acuminate, scabrous-awned, scabrous near midrib, otherwise glabrous. Staminate scales lanceolate to narrowly ovate, apex obtuse to acuminate, awnless, glabrous or sparsely ± appressed-pubescent near apex. Perigynia 12-18-veined, 4.8-6.5 × 1.4-2.4 mm, sparsely to densely pubescent; beak 1.4-2.6 mm, pubescent, teeth spreading, (0.4-)0.6-1.4 mm.

Fruiting Jun-Sep. Wet meadows, lakeshores, open, moist forests along streams; 1200-1900 m; Calif., Idaho, Nev., Oreg.