Culms 10-95 cm. Leaves 3-5 per culm; sheaths tight, inner band hyaline, 1.8-13 cm, apex concave, glabrous; ligule of distalmost leaf obtuse to rounded, 0.6-2.2 mm; blades plicate, 6-31 cm × 0.6-2.4(-2.7) mm, widest leaf 1-2.4(-2.7) mm wide. Inflorescences 0.8-3.7 cm; spikes 2-5(-7); lateral spikes pistillate often with few staminate flowers proximally, 3-9.5 mm, sessile, staminate portion 3-flowered, to 2.2 mm, pistillate portion 3-18-flowered, 2.3-8 mm; basal 2 spikes 2.1-11 mm apart; terminal spike 5.2-20 mm, gynecandrous, staminate portion 3-10-flowered, 2.2-14.5 × 0.7-1.4 mm, pistillate portion 4-16-flowered, 3-7 × 4-5.8 mm. Pistillate scales ovate, 1.2-2.1(-2.4) × 1-1.6 mm, apex obtuse. Staminate scales ovate, 1.4-2.9 × 1-1.3 mm, base clavate, apex obtuse to acute. Anthers 0.6-1.4 mm. Perigynia spreading to reflexed, castaneous to dark brown, 4-12-veined abaxially, sometimes faintly, 0(-6)-veined adaxially over achene, ovate, often convexly tapered from widest point to beak, forming a 'shoulder,' 1.95-3(-3.3) × 1.1-1.8 mm, 1.4-2(-2.2) times as long as wide; beak 0.4-0.95 mm, 0.18-0.44 length of body, setulose-serrulate, teeth 0.15-0.4 mm. Achenes ovate, 1.2-1.8 × 0.95-1.5 mm.

Fruiting late spring-early summer. Wet meadows, wet prairies, fens, coniferous and deciduous swamps, river and lakeshores, seeps; usually in ± calcareous, open sites; 0-2700 m; St. Pierre and Miquelon; Alta., B.C., Man., N.B., Nfld. and Labr. (Nfld.), N.W.T., N.S., Ont., P.E.I., Que., Sask., Yukon; Alaska, Ariz., Ark., Calif., Colo., Conn., Idaho, Ill., Ind., Iowa, Kans., Maine, Mass., Mich., Minn., Mo., Mont., Nebr., Nev., N.H., N.J., N.Y., N.Dak., Ohio, Oreg., Pa., S.Dak., Utah, Vt., Va., W.Va., Wash., Wis., Wyo.; Mexico (Chihuahua).

When Carex interior occurs with C. sterilis, C. echinata, and (rarely) C. atlantica, usually sterile intermediates, presumably hybrids, may occasionally be found.

Frequent to common except in southern Indiana; in tamarack bogs and swamps and on springy banks.

Common Name: inland sedge

Duration: Perennial

Nativity: Native

Lifeform: Graminoid

General: Densely tufted, with slender stems 20-50 cm tall, leaves reduced above.

Vegetative: Leaves all borne together on the lower part of the stem, not closely bunched, can equal the stems, flat and 1-2 mm wide.

Inflorescence: Spikes mostly 3-6, sessile, small and few flowered, some of the lateral spikes wholly pistillate, but the terminal one with a conspicuous, slender, staminate base, the bracts small and inconspicuous, shorter than the perigynia and hyaline or scarious except for the firmer greenish midvein, the perigynia 5-15 per spike, crowded, lower ones reflexed, broadest near the base, ovate to triangular, coriaceous and shining, thickened at base, 4-12 nerves on back, plano-convex, with raised marginal nerves, serrulate margined near tips and on beak, beak less than 1 mm long, fourth to half as long as body, achene lenticular about 1.5 mm long.

Ecology: Found in swamps, bogs, along creeks and streams, and in other wet locations from sea level to 9,000 ft (2743 m), flowers April-June.

Distribution: Ranges throughout the interior west, north to Canada and south into northern Mexico.

Ethnobotany: Unknown

Etymology: Carex is the classical Latin name for the genus, while interior means inside or inland.

Synonyms: Carex scirpoides

Editor: SBuckley 2012

Stems tufted, aphyllopodic, 2-9 dm, smooth; lvs 3-5 per stem, all in the basal third, shorter than to about equaling the stems, plicate, 1-2.5 mm wide; spikes (2)3-6, sessile, contiguous or ±remote, small and few-fld, the terminal one with a conspicuous, slender, staminate base, some of the lateral ones often wholly pistillate; bracts small and inconspicuous; anthers 0.6-1.4 mm; perigynia mostly 5-15, crowded, widely spreading or the lower reflexed, green or tan, planoconvex, coriaceous and shining, spongy-thickened at base, 4-12-nerved dorsally, nerveless or occasionally few-nerved ventrally, ovate or triangular-ovate, 2.2-3.2 נ1.1-1.8 mm, 1.4-2 times as long as wide, tending to be ±convexly tapered from the widest point to the beak, conspicuously serrulate-margined distally and on the beak, this short, broad, very shallowly bidentate, 0.5-1 mm, a fourth to half as long as the body; achene lenticular; 2n=54. Swamps, bogs, and other wet places; Nf. and Lab. to s. Yukon and Alas., s. to Va., Mo., and Mex.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

©The New York Botanical Garden. All rights reserved. Used by permission.