Herbs, perennial, cespitose, rhizomatous, tuberlike. Culms trigonous, 5-35 cm × 0.7-1.2 mm, glabrous. Leaves V-shaped, 5-25 cm × 1.5-3.5 mm, slightly scabridulous on abaxial margins, midrib. Inflorescences: spikes loosely ± globose, 15-25 mm wide; rays 1-10 cm; rachis 1-4 mm; bracts 3-7, ascending, V-shaped, 3-20 cm × 1-3 mm; rachilla deciduous, wingless. Spikelets 3-24, compressed, oblong-lanceoloid, 4-12 × 2.5-3.2 mm; floral scales deciduous, 3-9, pale reddish brown, ovate, laterally 3-5-ribbed, 2.5-3 × 2-2.4 mm , apex acute to obtuse. Flowers: anthers 1-1.2 mm; styles 0.4-0.6 mm; stigmas 1-2 mm. Achenes dark brown, ± stipitate, ellipsoid, 2-2.4 × 0.9-1.2 mm, apex obtuse, apiculate, surfaces glabrous, puncticulate, or papillose. 2n = 166.

Fruiting summer. Sand prairies, waste places, fallow fields; of conservation concern; 100-300 m; Ark., Ill., La., Mo., Tex.

Cyperus grayoides is in the Center for Plant Conservation´s National Collection of Endangered Plant´s. See frontispiece.