Tufted perennial 2–6 dm; stems smooth, scarcely thickened at base; lvs flat, soft, 3–6 mm wide; bracts 4–10, the longest surpassing the infl; rays 3–8, to 10 cm; spikes subglobose, 8–15 mm; spikelets 3–6-fld, to 10 mm, radiating in all directions from the short axis, deciduous at maturity; scales ovate, acute, 2.5–3 × 1–1.5 mm, multinerved; rachilla broadly winged; achenes trigonous, 1.3–1.7 mm, half as thick. Dry soil; trop. Amer., n. mostly on the coastal plain to N.J. and in the interior to Mo. (C. echinatus and C. globulosus, both misapplied)