Bot. Gaz. 9: 85. 1884.
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 setaceoustipped, usually exceeding all clusters, or at least all but the distal. Spikelets light redbrown 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.
Ala., Ark., Fla., Ga., Kans., La., Miss., Mo., N.C., Okla., S.C., Tenn., Tex., Va., Midwestern, se United States.
Varieties 2 (2 in the flora).
|1||Fruit body broadly obovoid to suborbicular, medially with mostly isodiametric tiny alveoli or pits, or minutely raised reticulate in an almost honeycomb pattern of alveolae, or simply evenly finely cancellate; ultimate spikelet complexes with clusters on stiffish branchlets, usually dense and exceeded at least by subulate tips of subtending leafy bract and bractlets.||Rhynchospora harveyi var. harveyi|
|1||Fruit body obovoid, lenticular, medially with oblong or roundish pitlike alveoli, intervals between contiguous transverse rows forming shallow, broad, pale, smooth ridges; ultimate spikelet clusters more sparse, on more slender, lax, erect to excurved branches and exceeding subtending bracts and bractlets.||Rhynchospora harveyi var. culixa|