Culms (3-)10-30(-40) cm × 0.4-0.8 mm. Leaves 5-20 cm × 0.8-2.7 mm. Inflorescences: spikes densely ovoid, 8-16 mm; rays 0 or 1-3, 1-4 cm; bracts 2-4, 4-15 cm. Spikelets 20-60, 3-7 × 2.5-3.5 mm; floral scales 3-7, 1.8-2.5 × 1.4-1.8 mm, margins clasping achene, apex mucronate, mucro 0.05-0.2 mm. Achenes 1.4-1.8 × 0.6-0.9 mm. Fruiting summer. Various well-drained, open places; 0-1000 m; N.B., N.S., Ont., Que.; Conn., Del., D.C., Ga., Ill., Ind., Iowa, Maine, Md., Mass., Mich., Minn., Nebr., N.H., N.J., N.Y., N.C., Ohio, Pa., R.I., Vt., Va., W.Va., Wis.