in A. Gray, Manual of Botany of the Northern United States (ed. 5) 542. 1867.
Herbs, perennial, not cespitose, rhizomatous, (3–)4.5–8(–9) dm. Rhizomes tuberous, 3–4 mm diam. Culms erect, terete, 2–3 mm diam., smooth. Cataphylls 0(–1), straw-colored, apex acute. Leaves: basal 1–2, cauline 2–4, auricles 0.5–3.5 mm, apex rounded, scarious; blade green to straw-colored, terete, 3–50 cm × 1–2 mm diam. Inflorescences terminal panicles of 2–10(–20) heads or a single head, 1–4(–10) cm, branches ascending; primary bract erect; heads 30–100-flowered, spheric, 8–10 mm diam. Flowers: tepals green to straw-colored, often red-tinted, lanceolate-subulate, apex acuminate; outer tepals 2.5–3.8 mm; inner tepals 2–3.2 mm; stamens 3, anthers 1/4–1/2 filament length. Capsules included, chestnut brown, 1-locular, obconic or ovoid, 1.8–2.7 mm, apex obtuse, valves separating at dehiscence, fertile throughout or only proximal to middle. Seeds ellipsoid to oblique-oblong, 0.3–0.4 mm, not tailed; cody clear to yellow-brown. 2n = 44.
Phenology: Fruiting mid summer–fall.
Habitat: Damp clayey, peaty, or sandy soils, swamps, ditches, ponds, wet woods, wet prairies
Elevation: 0–500 m
Ont., Ala., Ark., Conn., Del., Fla., Ga., Ill., Ind., Kans., Ky., La., Md., Mass., Mich., Minn., Miss., Mo., N.J., N.Y., N.C., Ohio, Okla., Pa., S.C., Tenn., Tex., Va., W.Va.