Dioecious Sedge

Culms 10–75 cm. Leaves 3–5 per culm; sheaths tight, inner band hyaline, 4–13 cm, apex concave, glabrous; ligules 0.3–1.7 mm, rounded to obtuse; blades plicate, 7.5–25 cm × 1.2–2.6 mm, widest leaf 1.6–2.6 mm wide. Inflorescences densely crowded distally, often with basal spikes ± separate, 0.9–4 cm; spikes 3–8; unisexual with pistillate and staminate spikes on different plants; pistillate plants rarely with few staminate flowers; staminate plants sometimes with few pistillate flowers scattered on spikes or, occasionally, entirely pistillate spikes mixed with entirely staminate ones in same inflorescence; proximal 2 spikes 3.8–15.5 mm apart, lateral spikes 3–13.5 mm, similar to terminal spikes; terminal spikes 3.5–13.7 mm, usually unisexual, pistillate spikes 5–26-flowered, 4.5–7.2 mm wide, staminate spikes 6–31-flowered, 1.2–2.6 mm wide. Pistillate scales ovate, 1.8–2.9 × 1–1.8 mm, apex acute. Staminate scales ovate, 2.2–3.3 × 1.1–1.8 mm, base not clavate, apex acute. Anthers (1–)1.2–2.2(–2.35) mm. Perigynia spreading to reflexed, castaneous to almost black, 5–12-veined abaxially, 0–10-veined adaxially, ovate to deltate, 2.1–3.8 × 1.2–2.2 mm, 1.4–2.3(–2.7) times as long as wide; beak 0.65–1.6 mm, 0.45–0.8 length of body, setulose-serrulate, teeth whitish, 0.15–0.5 mm, soft. Achenes ovate to suborbiculate, 1–1.7 × 0.9–1.3 mm.

Man., Nfld. and Labr. (Nfld.), Nunavut, Ont., Que., Sask.; Conn., Ill., Ind., Iowa, Maine, Mass., Mich., Minn., Mo., N.J., N.Y., Ohio, Pa., Tenn., Va., W.Va., Wis.

Fruiting late spring–early summer.

Fens, openings in white-cedar swamps, wet calcareous prairies, fresh interdunal meadows, calcareous seeps, lake and river shores, wet sunny limestone outcrops; 0–800m.

Carex elachycarpa Fernald; Kobresia elachycarpa (Fernald) Fernald

Carex sterilis Wilid. Sp. PI. 4: 208, in greater part. 1805
Carex scirpoides Schkuhr ; Willd. Sp. PI. 4: 208, in greater part. 1805. (Type from North America.)
Carex stellulala var. Torr. Ann. Lye. N. Y. 3: 387. 1836. (Based on C. sterilis Willd.)
Carex stellulala var. scirpoides Darl. Flora Cestr. 31. 1837. (Technically based on C. scirpoides
Schkuhr.) Carex stellulala var. sterilis Carey, in A. Gray, Man. 544. 1848. (Based on C. sterilis Willd.)
Very densely cespitose, the rootstocks very short, black, fibrillose, the culms slender but strict, usually 3-6 dm. high, dark-brown or brownish-black at base, exceeding leaves, sharply triangular and usually much roughened on angles above, clothed at base with the dried-up leaves of the previous year, the lower bladeless;. leaves with well-developed blades 3 or 4 to a fertile culm, on lower fourth, but not bunched, the blades 1-3 dm. long, 1.25-2.5 mm. wide, canaliculate or involute, green, stiff, very rough towards the long-attenuate apex, the sheaths tight, hyaline ventrally, thickened, concave, and yellowish-brown-tinged at mouth, wider than long; sterile culms similar, slender, well-developed; head 2-3 cm. long, the spikes 3-6, approximate or the lower more or less separate, very variable, pistillate, staminate, androgynous, or gynaecandrous, the culms frequently dioecious or nearly so, the spikes then being often entirely staminate or pistillate; pistillate spikes suborbicular to short-oblong, 4-6 mm. long and nearly as wide, the perigynia 3-15, widely spreading or somewhat reflexed at maturity; bracts short and scale-like, or the lowest more or less setaceous-prolonged; scales ovate, obtuse or somewhat cuspidate, with 3-nerved green center, a chestnut-brown (or in age brownish) intermediate band, and conspicuous shining white margins, the midvein obscure at apex, not sharply keeled, narrower but slightly longer than bodies of perigynia; staminate scales more obtuse and with more obscure midvein; perigynia plano-convex, ovate or ovate-lanceolate, 3 mm. long, 1.5-1.75 mm. wide, thick, subcoriaceous, yellowish-brown or brownish, sharp-edged to base, the margins little elevated, lightly severalto many-nerved both dorsally and ventrally, substipitate, spongy and truncate at base, rather abruptly contracted into a beak about half its length, the beak chestnut at apex, usually minutely white-hyaline dorsally at orifice, sharply bidentate, the upper margins of the body and the beak setulose-serrulate; achenes lenticular, broadly ovate, yellow, short-stipitate, apiculate, 1.5 mm. long, 1 mm. wide; style slender, straight, jointed with achene, at length deciduous; stigmas two, dark, slender, rather long.
Type locality: "Habitat in Pennsylvania"; according to Schkuhr. "Hab. in Pennsylvaniae graminosis humidis" (probably near Lancaster. Muhlenberg).
Distribution: Swampy meadows in calcareous regions, Newfoundland and Anticosti Island to Minnesota, and southward to New Jersey. Pennsylvania, and Illinois. (Specimens examined from Newfoundland. Quebec, Vermont, Massachusetts, Connecticut. New York. New Jersey, Pennsylvania, Ohio. Ontario. Michigan, Indiana. Wisconsin, Illinois, Minnesota.)

Carex elachycarpa Fernald, Proc. Am. Acad. 37: 492. pi. 5, f. 133, 134. 1902
Kobresia elachycarpa Fernald, Rhodora 5: 251. 1903. (Based on Carc.v elachycarpa Kernald.)
Very densely cespitose, the rootstocks very short, black, fibrillose, the culms slender, wiry, 2-5.5 dm. high, striate, triangular, roughened beneath head, strongly exceeding leaves, dark-brown at base and clothed with the short-bladed leaves of the previous year, the lowest bladeless; leaves with well-developed blades 2 or 3 to a fertile culm, on lower fourth, but not bunched, the blades erect or ascending, light-green, stiffish, up to 12 cm. long, 1-2 mm wide, canaliculate or involute, the sheaths tight, thin and hyaline ventrally, short -prolonged at mouth beyond base of blade and continuous with ligule; head narrow, 12-25 nun. Ion spikes 4-6, the lower more or less separated, the upper approximate, short-ovoid or suborbicular, 4-7 mm. long, 4-5 mm. wide, gynaecandrous, rounded at apex, rounded or short tapering at base, the perigynia 15 or less, closely appres led, many abortive, whole spikes being •■lien bracts scale-like or lowest slightly prolonged; scales ovate, acutish to short-cuspidate, light-chestnut-brown with lighter I 3-nervcd center and narrow dull-hyaline margins, sharply keeled, the mill vein prominent to apex, as wirle as imt simrtn than perigynia, : n 1 1 1 concealing them; pe ri g y nia plano-convi , oblong-lanceolate, 2.25 mm. long. 0.8 nun. wide, thick, yi llowishgreen or straw-colored or light-brownish, sharp edged to base bul not serrulate except ll
of beak, lightly scveral-striate on both faces, tapering and truncate at ba II , tapering at apex
into a serrulate beak one fourth to one lifth length of the whole, hyaline tipped, i -la burl brown-tinged, obliquely cu1 dorsally, bidentulate, th dorsal uturi conspicuous, thi ventral
lj membranaceous and fragile and broken bj elon
tion of maturing achene; achem s lenticular, linear oblong. 1.75 mm long, 0.6 nun wide,
bort-apiculate, yellowish, nearl) a thii I with
1 i I '.nun Id, MaimI'll illulnl . ( oUiti I
aii only from
•in.-. Pro. , . ,.l 37:/./ .i 133 134 Rob ■•■ fern Man I »JP;Britl Sc Brown, III. PI ed 2 I 917
n, i . i probabl) •■ hybrid between I

Carex sterilis, common names dioecious sedge, sterile sedge and Atlantic sedge, is a perennial plant native to North America.