Plants colonial; rhizomes long-creeping. Culms central, coarse, trigonous, 40-110 cm, smooth. Leaves: basal sheaths pale green to brownish or pale red tinged, base with marescent remains of previous year´s leaves; longest ligules 2-10(-12) mm, less than 2 times longer than wide; blades glaucous, flat to V-shaped, (4-)5.5-13 mm wide, glabrous. Inflorescences 15-50 cm; proximal 2-4 spikes pistillate, ascending to arching; distal spikes erect; terminal 3-6 spikes staminate. Pistillate scales lanceolate to ovate, apex obtuse to acute, glabrous, awn 0.9-8.5 mm, scabrous. Perigynia ascending, obscurely 10-15-veined, veins somewhat impressed, narrowly ovoid, (4.5-)5.5-7.7 × 1.6-3 mm, glabrous; beak obscure, 0.9-1.7 mm, bidentulate, teeth straight, 0.4-0.8 mm. Fruiting Apr-Jul. Swamp forests, river bottoms, shores of streams, ponds and lakes, wet meadows, often in clay soils, seasonally moist sites; 0-400 m; Ont.; Ark., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Md., Mich., Miss., Mo., Nebr., N.C., Ohio, Okla., Pa., S.C., Tex., Va. Carex hyalinolepis is abundant in the Mississippi lowlands and often dominant in the understory of open, wet floodplain forests and bottomland meadows. It is a rapid invader of ditches and other disturbed areas. Sometimes extensive stands are seen without fertile culms. Occasionally, Carex hyalinolepis hybridizes with C. pellita (= C. ×subimpressa Clokey, according to A. A. Reznicek and P. M. Catling 1986), and rarely with C. lacustris. Carex ×subimpressa is sufficiently frequent that it has been treated as a species in some floras. It can form large colonies in suitable sites.