Plants densely cespitose. Culms 14-89(-101) cm × 0.3-1.1 mm wide, smooth or papillose. Leaves: ligule on distal leaf 0.9-2.2 mm, as long as wide; blades 0.6-4.2 mm wide, widest blade 2.4-4.2 mm wide. Inflorescences 12-56 mm; proximal internode 6-34 mm; proximal bracts 6-49 mm, awn 7-46 mm; spikes (2-)3-5, longest ones 2-5, usually gynecandrous; proximal spikes with 1-2 staminate and (5-)7-12 pistillate flowers, 5.2-11(-13) × (2.1-)3.7-6.9 mm; terminal spikes usually with 1-3(-5) staminate and (7-)9-13(-16) pistillate flowers, 6.8-13 × 3.8-8.1 mm. Pistillate scales with colorless or stramineous margins, 3-4.5 × 1.6-2.2 mm, body 2.8-4.2 mm, apex acuminate to short-awned, awn to 0.6 mm. Staminate scales with colorless or stramineous margins, 3-5.3 × 1.2-1.6 mm, apex acute to acuminate or occasionally short-awned to 0.3 mm. Anthers (1.8-)1.9-2.2 mm. Perigynia erect to ascending, green to pale brown, 0-5-veined abaxially, usually veinless adaxially, narrowly ovate, 4-4.9(-5.2) × 1.3-1.5(-1.6) mm, 2.9-3.8 times as long as wide, apex gradually tapering; beak 1.4-2.1 mm, 0.32-0.4 times as long as perigynia, margins serrulate, apex entire or bidentulate, teeth to 0.2 mm, 0-0.05 times as long as perigynia. Stigmas 1.9-2 mm. Achenes 1.8-2.2 × 1.2-1.5 mm wide, 1.3-1.8 times as long as wide.