Culms 20-90 cm, pilose. Leaves: ligules shorter than wide; blades 1.5-4 mm wide, pilose on both surfaces. Inflorescences: lateral spikes 8-18 × 3-5.5 mm, usually crowded; terminal spike gynecandrous, at least 1/2 of flowers pistillate, 10-20(-25) mm. Pistillate scales ovate, 1.8-2.5 × 0.7-1.3 mm, apex obtuse, sometimes mucronate, shorter than perigynia. Staminate scales ovate to lanceolate, 2.1-5.2 mm, apex acuminate. Anthers 1.3-2.2 mm. Perigynia ascending, weakly 9-18-veined, obovate-circular, ± trigonous in cross section, 2-3 × 1.1-1.6 mm, not papillose, glabrous; beak absent. Achenes 1.6-2.1(-2.6) × 0.8-1.3 mm. 2n = 52.
Common in southern Indiana, usually in sterile soil, in dry open woods and fallow fields and along sandy roadsides; infrequent in low or flat woods; becoming less frequent northward and rare in the northernmost counties.