Glomerate Sedge

Carex aggregata may be difficult to distinguish from C. gravida if the leaf sheaths are damaged or not visible on specimens.

Plants without conspicuous rhizomes. Culms (20–)30–100 cm, 1.5–3.5 mm wide basally, 0.7–1.2 mm wide distally. Leaves: sheaths usually loose, proximal green-and-white-striped and green-and-white-mottled, with conspicous transverse veins on back, fronts white to hyaline, sometimes red dotted and transversely rugose, yellow or brown and thickened at mouth; ligules 1–4.5 mm, shorter than to as long as wide; widest leaf blades 3.5–5 mm wide. Inflorescences with 5–10 spikes, (1.5–)2–5 cm × 8–13 mm; proximal internodes shorter than to as long as proximal spikes; proximal bracts to 3 cm; spikes with 5–15 ascending to spreading perigynia. Pistillate scales hyaline or pale brown with green, 1–3-veined center, ovate, 2.2–3.5 × 1.2–1.8 mm, body 2/3 as long to almost length of perigynia, apex acuminate to short-awned. Anthers 1.5–2.5 mm. Perigynia pale green to pale brown, veinless or weakly 2–5-veined abaxially, 3.4–4.6 × 1.9–2.8 mm, body somewhat spongy, thickened at base, margins serrulate distally; beak 0.7–1.4 mm, apical teeth 0.3–1 mm. Achenes circular to elliptic-circular, 1.8–2.1 × 1.6–1.8 mm.

Ont.; Ala., Del., D.C., Ill., Ind., Iowa, Ky., Md., Minn., Mo., N.J., N.Y., N.C., Ohio, Okla., Pa., S.Dak., Tenn., Va., W.Va., Wis.

Fruiting late spring.

Meadows, thickets, open forests, usually on calcareous soils; 50–300m.

Carex agglomerata Mackenzie, Bull. Torrey Bot. Club 33: 442. 1906, not C. B. Clarke 1903; C. sparganioides Muhlenberg ex Willdenow var. aggregata (Mackenzie) Gleason

Carex aggregata Mackenzie, Bull. Torrey Club 37: 246. 1910
Carex agglomrrata Mackenzie. Bull. Torrey Club 33: 442. 1906. (Type from Missouri.) Not
C. agglomerata C. B. Clarke, 1903.
Rootstocks lignescent but rather slender, conspicuously short-creeping, brownish or
blackish, fibrillose. the culms 4 10 dm. high, erect, ascending, or even decumbent, usually
considerably exceeding the leaves, sharply triangular, smooth below, slightly rough immediately
Ith the bead, light-lirownisli-tinged at base; leaves regularly and evenly distributed on
the lower part of the culm and not chiefly tufted near the base, the blades Hat. light-green,
• it, is dm. Ion/. 3 6 mm wide, smooth towards the base, roughened towards tinapex
and on the margins; sheaths conspicuously green-. in.l-wliite-iiio ttll id and Septate -nodulose
I , whitened but not es ily brolo n vi rurally, usually not transversely rugulose, concave,
d and thickened al mouth, the ligule widi i thou long, nol dark-margined;
in a terminal head 2 5 5 cm. long, 10 mm thick, the Iowa
rate and the upper closely aggregated, the few inconspicuou lUminati
Bowers terminal and the { 15 aacendio ia bekw brad iwl-
shaped, don ually conspicu horter than the head,
i,„ t r, tt ,, (mall, i inn. greenish-hyaline with a green midrib,
acun,.,: • iboul the length of the bodic ol the perigynia, but omewhat nai rower; perigynia plano-convex, ovate, sharp-edged to base and serrulate to the middle, deep-green, 3.25-4.5 mm. long, about 2 mm. wide, membranaceous, flat ventrally, sessile, round-truncate at base, nerveless ventrally, obscurely few-nerved dorsally, tapering into a serrulate beak about half the length of the body, bidentate, the teeth sharp, erect, whitehyaline within, the sutures on both sides conspicuous; achenes lenticular, oblong-orbicular, 2 mm. long, very short-stipitate, minutely apiculate: style slender, straight, jointed with achene, slightly thickened at base; stigmas two, reddish-brown, slender, elongate.
Type locality (of C. agglomerata Mackenzie, on which C. aggregata is based) : Courtney, Jackson County, Missouri (B. F. Bush 1718).
Distribution: Rich woods in calcareous districts, western New Jersey to District of Columbia, and westward to Kansas and Oklahoma. (Specimens examined from western New Jersey, New York, Pennsylvania, District of Columbia, Ohio, Indiana, Kentucky, Illinois, Iowa, Missouri, Kansas, Oklahoma.)

Carex aggregata is a species of sedge that was first described by Kenneth Mackenzie in 1910. It is native to the eastern United States and Canada.