Ann. Lyceum Nat. Hist. New York 1: 68. 1824.
Plants densely cespitose; rhizomes ascending to erect, reddish-brown, 0–10 mm, stout. Culms 8–27 cm, scabrous distally; bases (remnants of old leaves) strongly fibrous. Leaf-blades green, greatly exceeding culms, 1.4–4 mm wide, herbaceous, papillose to scabrous abaxially, papillose to scabrous adaxially. Inflorescences with both staminate and pistillate spikes; peduncles of staminate spikes 0.3–0.8 mm; proximal cauline bracts leaflike, usually shorter than inflorescences. Spikes: proximal pistillate spikes 2–3 (basal spikes 0); cauline spikes overlapping, proximal 2 separated by less than 7 mm, with 6–15 perigynia; staminate spikes 5.3–10 × 1.1–2.3 mm. Scales: pistillate scales pale to, usually, dark reddish-brown to purplish brown, with similarly colored or narrow white margins, ovate to lanceolate, 2.9–3.7 × 1.2–2 mm, equaling or exceeding perigynia, apex acute to acuminate or cuspidate; staminate scales ovate, 3–4.3 × 1–1.8 mm, apex obtuse to acute or acuminate. Anthers 1.4–2.6 mm. Perigynia pale green, veinless, ellipsoid, 2.8–3.6 × 1–1.3 mm, longer than wide; beak straight, pale green, 0.7–1 mm, weakly ciliate-serrulate, apical teeth 0.1–0.4 mm. Stigmas 3. Achenes brown, ellipsoid, obtusely trigonous in cross-section, 1.4–2 × 0.9–1.2 mm. 2n = 36.
Phenology: Fruiting early Apr–late Jun.
Habitat: Acidic soils of rocky, dry woods, thickets, and clearings, in partial shade of mixed hardwood-pine forests or full sun along open roadsides and clearing edges, often adjacent to streams
Elevation: 10–800 m
Ont., Ala., Ark., Conn., Del., D.C., Ga., Ill., Ind., Ky., Mass., Miss., Mo., N.J., N.Y., N.C., Ohio, Pa., R.I., S.C., Tenn., Va., W.Va.