Scirpus barbatus Rottbøll, Descr. Pl. Rar., 27. 1772; Bulbostylis floridana (Britton) Fernald; Isolepis barbata (Rottbøll) R. Brown; Scirpus dussii Boeckeler; Stenophyllus floridanus Britton ex Nash

Herbs, annual, densely cespitose, scapose, low. Culms 5–20(–30) cm. Leaves to 2/3 length of scapes; sheaths greenish or tan, glabrous or hispidulous on ribs; blades spreading, filiform, 0.5 mm wide, involute, margins scabridulous. Inflorescences: scapes filiform, coarsely few ribbed, to 0.5 mm thick; spikelets in terminal headlike, involucrate clusters, 1–1.5 cm wide; involucral bracts with setaceous blades rarely exceeding inflorescence. Spikelets red to red-brown or dull brown, lance-ovoid to lanceoloid or linear oblong; fertile scales lanceolate, keeled, 1.2–2.2 mm, glabrous, midrib excurrent as mucro. Flowers: stamens 1; anthers oblong, 1 mm. Achenes trigonous, obovoid, 0.5–0.6 mm, angles often sharp, faces flat or slightly concave, finely reticulate; tubercle a small button. 2n = 10.

Fruiting summer–fall. Moist to dry sands and sandy peats, weedy in open disturbed sandy sites; 0–500 m; Ala., Fla., Ga., La., Miss., N.C., S.C., Tenn., Tex.; West Indies (Martinique); Central America; tropical Africa (including Madagascar); tropical Asia (including Indonesia); tropical Atlantic Islands; Indian Ocean Islands; tropical Pacific Islands; tropical Australia.