Bull. Misc. Inform. Kew, addit. ser. 8: 26. 1908.
Herbs, annual, densely cespitose, scapose. Culms (5–) 10–20 cm. Leaves 1/2–2/3 length of culms; sheaths brownish to stramineous, glabrous or scabrid along ribs; blades spreading-recurved, filiform, 0.5 mm wide, involute, margins and adaxial ribs hispidulous. Inflorescences: scapes erect to spreading, wiry, angularly ribbed, 0.6–1 mm thick, hispidulous; spikelets in dense, terminal, top-shaped to hemispheric involucrate heads, 1–1.5 cm wide; longer involucral bracts with setaceous blades many times exceeding heads, gradually dilating to scarious-bordered, entire sheaths. Spikelets usually greenish or dull brown, oblong to lance-ovoid, 3–5 mm; fertile scales ovate, keeled, 3–4 mm, abaxially hirtellous, midrib excurrent forming excurved mucro, scabrid. Flowers: stamens 1; anthers oblong, 0.5 mm. Achenes pale or graybrown, broadly trigonousobovoid, rather sharply 3-ribbed, 1 mm, faces flat or somewhat concave, finely transversely rugose; tubercle a depressed-conic button. 2n = 30.
Phenology: Fruiting summer–fall.
Habitat: Moist sands or sandy peats of sandhill swales, fields, pineland savanna, and waste areas, often weedy
Elevation: 0–200 m
Fla., Ga., N.C., S.C., West Indies (Cuba).