Herbs, perennial, rhizomatous. Culms trigonous, 50–100 cm × 2.5–3 mm, glabrous. Leaves V-shaped, 20–50 cm × 4–7 mm. Inflorescences: spikes loosely ovoid, 1.5–7 cm wide; rays 5–13, 1–21 cm; 2d order rays 0.5–3 cm; bracts 3–8, V-shaped, 5–50 cm × 2.5–5.6 mm; rachilla persistent, wings 0.4–0.6 mm wide. Spikelets 5–30, compressed, linear, (5–)12–40 × 1.5–2.2 mm; floral scales deciduous, 6–24, reddish brown to yellowish brown laterally, greenish medially, 5–7-ribbed, elliptic, 3–4 × 1.4–1.6 mm, apex obtuse. Flowers: anthers 1.5–2 mm; styles 2–2.3 mm; stigmas 2–3 mm. Achenes dark brown, sessile, oblong, 1.5 × 0.4–0.5 mm, apex apiculate, surfaces puncticulate.

Fruiting summer. Ditches, croplands; 100–1000 m; Kans., Mo., N.Mex., Okla., Tex.