Ann. Lyceum Nat. Hist. New York 3: 372. 1836.
Rhizomes to 10 cm × 2 mm. Culms 0.3–1 m × 1–2 mm. Leaves: blades conduplicate to subinvolute, (1–) 2–3.5 mm wide, smooth or nearly so. Inflorescences terminal or lateral and terminal, pedunculate, peduncle mostly covered by subtending leaf-sheath, 15–25 cm; 1st and 2d order branches (rarely congested and with little obvious branching), branches stiffly ascending. Spikelets in groups of 3–5 (–30), narrowly ellipsoid to lanceoloid; floral scales 5–6, the proximal chestnut-brown, ovate to oblong-lanceolate, 2.5–3 × 2 mm, midvein conspicuous, lateral-veins weak; stamens 2; anthers 2 mm, connective apices 0.1 mm; styles 2–2.5 mm; stigmas 1–1.5 mm. Achenes whitish or pale green, ovoid, 2.5–3 × 1.5–1.7 mm, base 3–6-lobed, discoid, truncate and impressed, flared, apex subacute, irregularly rugulose longitudinally, glossy.
Phenology: Fruiting summer–early fall.
Habitat: Open acidic to alkaline wetlands, brackish upper edges of tidal marshes
Elevation: 0–400(–1200) m
Man., N.B., Nfld. and Labr., N.S., Ont., Que., Sask., Conn., Del., Fla., Ill., Ind., Maine, Md., Mass., Mich., Minn., N.H., N.J., N.Y., N.C., Ohio, Pa., R.I., S.C., Tenn., Tex., Vt., Wis.