Culms 10-50 cm × 0.4-1.7 mm. Leaves 12-40 cm × 0.8-3.5 mm. Inflorescences: spikes loosely to densely ovoid, 8-16 mm; rays 0or 1-4, 1-6 cm; bracts 2-4, 6-25 cm. Spikelets 15-40(-60), 6-22 × 3-4 mm; floral scales 5-22, 2.5-4 × 2-2.6 mm, margins not clasping achene. Achenes 1.7-2.2 × 0.8-1.2 mm. Fruiting summer. Well-drained, open roadsides, fields, prairies; 0-1700 m; Ont.; Ark., Colo., Conn., Del., Idaho, Ill., Ind., Kans., Ky., Mass., Mich., Minn., Mo., N.J., N.Y., N.C., Ohio, Oreg., Pa., R.I., Tenn., Tex., Vt., Va., W.Va., Wis.