Plants perennial, cespitose or solitary, to 70 cm; rhizomes slender, scaly, to 2 mm thick. Culms erect, slender, leafy-based, trigonous, several-ribbed. Leaves spreading to erect, overtopped by culm; blades narrowly linear, proximally flattened, 0.5-3 mm wide, apex tapering, trigonous. Inflorescences terminal, solitary, headlike, dense, white, leafy-involucrate; involucral bracts several, flaring to recurved, white from broadened base nearly to median, then green to tapered tip, longer bracts 13 cm × 2-7 mm. Spikelets white, ovoid, 5-7 mm, apex acute; fertile scales many, boat shaped, sharply curved keeled, 3-4(-5) mm, apex acute or blunt. Flowers: perianth absent. Fruits several per spikelet, 1.5-1.7(-2) mm; body yellow to mahogany, broadly pyriform obovoid, tumidly lenticular, 1 × 0.5-0.7 mm, widest at apex, margins thickened, interrupted at base of tubercle; surfaces transversely undulate rugose, ridges contiguous, of short linear papillae; tubercle broadly triangular, 0.5-0.6 mm, gray crustaceous, apex short acuminate. 2n = 12. Fruiting late spring-summer. Sands, peats, and silt of interdunal swales, shores, meadowy swales, and marsh edges, sometimes fens, usually on circumneutral or basic substrates; 0-300 m; Ala., Ark., Fla., Ga., La., Miss., N.C., S.C., Tex., Va.; Mexico; West Indies; Central America; South America (French Guiana). Rhynchospora colorata is a slender and clonal version of R. latifolia, with a distinct preference for more basic substrates; involucral bracts are very slender and have a longer portion of green, usually reaching well proximal to midbract. See also 16. Rhynchospora latifolia.
Stems slender, 2-6 dm, solitary or few together on slender stoloniform rhizomes; blades 2-3 mm wide, usually shorter than the stem; spikelets whitish, compressed at anthesis, more fusiform at maturity, 4-7 mm, numerous in a dense terminal head subtended by 4-7 widely spreading, linear, foliaceous, very unequal, conspicuously bicolored bracts with a white base; scales keeled, ca 8-12, not much imbricate, only 1-3 subtending perfect fls, the others with staminate fls or some empty; perianth wanting; achenes obovate, 1 mm, transversely rugose, capped by the paler, depressed tubercle. Damp, often sandy soil; se. Va. to Mex. and W.I. (Dichromena c.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.