Culms subterete to slightly compressed, to 2 times as wide as thick, (0.2-)0.5-1 mm wide. Distal leaf sheaths often with tooth, to 0.1(-0.5) mm. Fruiting spring-summer. Seasonally wet seeps and depressions in calcareous grasslands, meadows, open oak woods, ditches, sometimes limestone, rarely saline marsh or lakeshores; 10-2300 m; B.C., Man., Sask.; Colo., Ill., Iowa, Kans., Minn., Mo., Nebr., N.Mex., N.Dak., Okla., S.Dak., Tex. Some specimens herein included in E. compressa var. acutisquamata are intermediate with E. elliptica in their floral scales, including the single record from British Columbia. Eleocharis compressa var. acutisquamata probably occurs in Alberta; I have not seen specimens.