Much like no. 216 [Carex vesicaria L.]; stems 4-8 dm, tufted on short rhizomes; lvs soft and flat, the main ones 2-4 dm נ3-6 mm; staminate spikes usually 2, widely separated, much elevated above the pistillate, these 2-4, well separated, cylindric, 2-5 cm; perigynia numerous, imbricate and ascending in ca 6 rows, 7-10 נ(4-)4.5-7 mm, inflated and very thin-walled, broadly ovoid, the conic summit tapering into a slender beak 2 mm, its teeth 0.5-1 mm; achene trigonous, obovoid, 3-4 mm, deeply indented in the middle of one angle. Swampy woods, pond-margins, and wet meadows; N.B. to Minn., s. to N.J., O., and Io.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Frequent in northeastern Indiana; otherwise known in the state only from the dune area and from Floyd County. It is found in swales in woods, swamps, and on borders of ponds, frequently in shallow water.