Plants perennial, cespitose, 70-110 cm; rhizomes absent. Culms erect to excurved, leafy, obscurely trigonous, slender. Leaves spreading to ascending, shorter than culm, crowded toward culm base; blades linear, proximally flat, 1-3 mm wide, gradually involute, apically trigonous, subulate. Inflorescences: spikelet clusters 1-4, dense to open, mostly irregularly turbinate; peduncles ascending, branches spreading to erect, ultimate branches with many spikelets; leafy bracts setaceous tipped, usually exceeding all clusters, or at least all but the distal. Spikelets light red brown or brown, broadly ellipsoid to lanceoloid, 3-4 mm, apex acute to acuminate; fertile scales ovate to obovate or suborbiculate, 2-3.5 mm apex acute to rounded or emarginate, midrib included or exserted as mucro. Flowers: perianth bristles mostly 6, rarely reaching fruit midbody, antrorsely barbellate. Fruits mostly 1 per spikelet, 2-2.5 mm, body dark brown, obovoid to subglobose, tumid or lenticular, 1.5-1.7 mm, transversely finely rugose to nearly level, intervals with very small, pitlike alveoli.
Much like no. 21 [Rhynchospora grayi Kunth]; spikelets globose-ovoid, 2.5-3 mm; bristles delicate, often caducous, half to nearly as long as the achene; achenes brown, 1.5-1.8 mm; tubercle 0.3-0.5 mm. Acid soils, chiefly on the coastal plain; se. Va. to Fla. and Tex., n. inland to Mo.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.