Greater Bladder Sedge

Plants from the south of the species range and from lower elevations northward are usually more robust and have more inflated, ovoid perigynia than northern or high-elevation plants. The latter are sometimes distinguished as Carex intumescens var. fernaldii L. H. Bailey.

Plants cespitose or not, short-rhizomatous. Culms solitary or not, erect, (15–)30–80(–140) cm. Leaves 6–12; basal sheaths purplish red; sheath of distal leaf 0–1(–2.5) cm; ligules rounded, 1–8 mm; blades 8–27 cm × 3.5–8 mm. Inflorescences 2–15 cm; peduncles of proximal pistillate spikes 0.3–1.5 cm, basal 2 peduncles 0.2–2.1 cm apart; of terminal spike 0.5–4 cm; bracts leafy, sheathless, blades 6–21 × 2–6 mm. Spikes: proximal pistillate spikes 1–4, often closely aggregated and difficult to distinguish, 1–12-flowered, ovoid to obovoid, 1–2.7 × 1–2.8 cm; terminal staminate spike 1, 1–5 cm × 1–3 mm. Pistillate scales 1–3-veined, lanceolate-ovate to ovate, 4–9.5 × 2–3.8 mm, apex acute to awned, awns rough, to 6.5 mm. Anthers 3, 2–4 mm. Perigynia ascending to spreading or the basalmost reflexed, strongly 13–23-veined, lanceoloid to ovoid, 10–16.5 × 2.5–6.5 mm, with satiny luster, glabrous; beak poorly defined, 2–4.2 mm. Achenes sessile, ellipsoid to obovoid, flat to convex faces, angles not thickened, 3.5–5.7 × (2.2–)2.5–3.9 mm; style same texture as achene.

Man., N.B., Nfld. and Labr., N.S., Ont., P.E.I., Que.; Ala., Ark., Conn., Del., D.C., Fla., Ga., Ill., Ind., Iowa, Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., S.Dak., Tenn., Tex., Vt., Va., W.Va., Wis.

Fruiting late spring–early summer.

Dry-mesic to wet coniferous, mixed, and deciduous forests, forest openings, thickets, wet meadows, ditches; 0–2000m.

Carex intumescens Rudge, Trans. Linn. Soc 7:97. pi. 9, f. 3. 1804.
" Carex folliculata L." Wahl. Sv. Vet.-Akad. Nya Handl. 24: 152. 1803.
Carex folliculata var. major Pursh, Fl. Am. Sept. 1: 42. 1814. (Based on C. intumescens Rudge.)
Carex folliculata C. intumescens Dewey, Am. Jour. Sci. 10: 32. 1825. (Based on C. intumescens
Rudge.) Carex folliculata var. major Kunth, Enum. PI. 2 : 499. 1837. (Based on C intumescens Rudge.) Carex intumescens var. Fernaldii L. H. Bailey, Bull. Torrey Club 20: 418. 1893. (Type from
Aroostook County, Maine.) Carex Grayi var. rariflora Farwell, Rep. Mich. Acad. 22 : 181. 1921. (Type from Detroit, Michigan.)
Cespitose, the rootstocks very short, without long horizontal stolons, thickish, tough, blackish, the clumps large, the culms 3-10 dm. high, leafy throughout, slender but stiff, much exceeded by the upper leaves, phyllopodic, sharply triangular, roughened beneath the head, purplish-red at base; sterile shoots elongate, conspicuous; leaves with well-developed blades 8-15 to a fertile culm, septate-nodulose, the lower clustered, the upper scattered and exposing the internodes, the blades erect-ascending, flat, dull-green, thin but firm, usually 1-3 dm. long, 2.5-9 mm. wide, averaging 3-5 mm., long-attenuate, the upper half very rough on the margins, the sheaths rather loose, white-hyaline ventrally, short-prolonged at mouth beyond base of blade, the ligule about as long as wide or shorter; staminate spike solitary, usually with a bract, shortto long-peduncled, narrowly linear, 1.5-5 cm. long, 2 mm. wide, the peduncle rough, the scales rather loose, lanceolate, cuspidate to obtuse, light-yellowish-red with green center and hyaline margins; pistillate spikes 1-3, aggregated, erect, on peduncles about the length of the spikes to nearly sessile, globose or subglobose, 1-2.5 cm. long and about as wide, the perigynia 1-15 (usually 5-10), spreading to erect; bracts leaf -like, much exceeding the culm, sheathless or short-sheathing, the sheaths short-prolonged upward at mouth beyond base of blade ; scales ovate or ovate-lanceolate, 3-nerved, tapering into a serrulate awn, mostly strongly cuspidate, varying to obtuse, white-hyaline with green center, much narrower and shorter than the perigynia; perigynia broadly or narrowly ovoid, 10-17 mm. long, 3.5-8 mm. wide, strongly inflated, suborbicular in cross-section, glabrous, shining, green, membranaceous, strongly about 15-ribbed, rounded at base, sessile or nearly so, tapering into a normally smooth or nearly so, broad, conic, bidentate beak 2-3.5 mm. long and about one fourth the length of the whole, the teeth 1 mm. long, stiff, hispid within, erect or nearly so; achenes oblong-obovoid, very loosely enveloped, 5 mm. long, 3 mm. wide, triangular with blunt angles and the sides concave below, yellowish-white, sessile, short-tapering above, conic-apiculate and continuous with the slender, normally straight, persistent style; stigmas 3, slender, blackish, short.
Type locality: "Habitat in Carolina."
Distribution: Swampy or moist woods, acid soils, Newfoundland to Keewatin, and southward to Florida and Texas. (Specimens examined from Newfoundland, Miquelon, Prince Edward Island, Quebec, Nova Scotia, New Brunswick, Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Pennsylvania, Delaware, Maryland, District of Columbia, Virginia, West Virginia, North Carolina, South Carolina, Georgia, Florida, Alabama, Mississippi, Ontario, Ohio, Michigan, Wisconsin, Indiana, Tennessee, Keewatin, Minnesota. Iowa. Missouri, Arkansas, Louisiana, Texas.)

Carex intumescens, also known as bladder sedge, is a species of Carex native to Canada and the eastern United States.