Carex seorsa Howe

Carex seorsa very rarely hybridizes with C. atlantica subsp. atlantica.

Carex seorsa is unusual in sect. Stellulatae in its primarily forest understory habitat, lax, spreading habit, perigynia widest in the middle, and smooth perigynia beaks. Its affinities require further study.

Culms 15–75 cm. Leaves 2–4 per culm; sheaths with inner band hyaline, 3.5–12 cm, apex deeply concave, glabrous; ligules 1.7–7 mm, apex acute or often emarginate; blades plicate to flat, 9–50 cm × 0.8–3.9 mm, widest leaf 2.1–3.9 mm wide. Inflorescences 1.8–7 cm; spikes 4–8; lateral spikes pistillate often with few staminate flowers proximally, 2.8–10.8 mm, sessile, staminate portion (0–)1–6-flowered, (0–)0.8–4.6 mm, pistillate portion 4–25-flowered, 2–7.6 mm; basal 2 spikes 5–27 mm apart; terminal spike gynecadrous, 4.7–16.5 mm, staminate portion 3–13-flowered, 1.8–12.7 × 0.9–2.1 mm, pistillate portion 6–23-flowered, 2.8–7.3 × 4.4–6 mm. Pistillate scales ovate, 1.2–2.2 × 1–1.6 mm, apex acute. Staminate scales ovate, 1.7–3.3 × 1–1.4 mm, apex acute. Anthers 1–1.9 mm. Perigynia spreading to reflexed, green, 6–14-veined abaxially, 0–6-veined adaxially over achene, elliptic to elliptic-ovate, 1.8–2.9 × 1–1.9 mm, 1.2–2.1 times as long as wide; beak 0.2–0.6 mm, 0.09–0.33 length of body, smooth. Achenes ovate to orbiculate, 1.2–1.6 × 0.85–1.4 mm.

Ont.; Ala., Ark., Conn., Del., D.C., Fla., Ga., Ind., Ky., Md., Mass., Mich., Miss., N.H., N.J., N.Y., N.C., Ohio, Pa., R.I., S.C., Tenn., Va.

Fruiting late spring–early summer.

Acidic, sandy, peaty hardwood or Chamaecyparis swamps, thickets; 0–300m.

Carex seorsa Howe; Gordinier & Howe, Fl. Renss. Co. 39. 1894.
Carex rosaeoides Howe; Gordinier & Howe, Fl. Renss. Co. 33. 1894. (A name for which C.
seorsa was substituted.) "Carex canescens var. vulgaris L. H. Bailey" Deane, Fl. Metrop. Park Comm. 95. 1896.
In large dense clumps, the rootstocks not at all prolonged, the culms weak, 3-7 dm. high, sharply triangular, flattened in drying, roughened above, usually exceeding the leaves, lightbrown at base, conspicuously clothed with the dried-up leaves of the previous year, the lower bladeless; leaves with well-developed blades about 3 to a fertile culm, on the lower third, but not bunched, the blades erect-ascending, flat, green, thin, usually 2.5-3.5 dm. long, 2-4 mm. wide, very rough towards the apex, the sheaths tight, very thin and hyaline ventrally, concave at mouth, the ligule short; spikes 3-7, in a head 3-7 cm. long, the lower separate, the upper approximate, the lower spikes 1-2 cm. apart, the terminal spike 6-12 mm. long, peduncled and varying from narrowly linear, 1 mm. wide and all staminate, to oblong, 4-6 mm. wide and the staminate flowers occupying the clavate base, the lower spikes oblong to shortorbicular, 4-7 mm. long. 4-6 mm. wide, containing 5-20 at length widely radiating excurved perigynia and a few staminate flowers at base; bracts scale-like or the lowest occasionally prolonged, shorter than the head; scales orbicular-ovate, obtusish or acutish to cuspidate, dull-whitish-hyaline, prominently keeled to apex with the brownish or greenish midrib, narrower and from little to much shorter than bodies of perigynia; staminate scales longer; perigynia concavo-convex, broadly oval, 2.5 mm. long, 1.5 mm. wide, membranaceous, deepgreen, the body broadest near middle, somewhat spongy at base, narrowly sharp-edged, the edges thick, not serrulate, strongly several-nerved both dorsally and ventrally, short-stipitate, round-truncate at base, abruptly narrowed into a short beak about one fourth to one fifth of length of body, white-tipped, shallowly bidentate, smooth-margined (or nearly so), its teeth very' short and erect, the false suture on ventral face obscure, obliquely cut dorsally and with the suture more pronounced; achenes lenticular, occupying upper part of body of perigynium, short-stipitate, broadly ovate, minutely apiculate, 1.25 mm. long, 1 mm. wide; style very' short, somewhat enlarged at base, jointed with achene, at length deciduous; stigmas two, slender, light-reddish-brown, rather short.
Type locality: Lansing's Grove. Rensselaer County, New York.
DisTRrBiTioN: Acid soils in swampy woods, Massachusetts to Georgia, mostly east of the mountains, and locally westward to Ohio and northwestern Indiana. (Specimens examined from Massachusetts, Connecticut, Rhode Island, New York, New Jersey, Pennsylvania, Maryland, District of Columbia. Virginia, North Carolina, Georgia, Ohio. Indiana.)

Carex seorsa adalah spesies tumbuhan seperti rumput yang tergolong ke dalam famili Cyperaceae. Spesies ini juga merupakan bagian dari ordo Poales. Spesies Carex seorsa sendiri merupakan bagian dari genus Carex. Nama ilmiah dari spesies ini pertama kali diterbitkan oleh Howe.

Carex seorsa là một loài thực vật có hoa trong họ Cói. Loài này được Howe mô tả khoa học đầu tiên năm 1896.