White Edge Sedge

Carex flexuosa Muhl.; Wilid. Sp. PI. 4: 297. 1805
Carex tenuis Rudge, Trans. Linn. Soc. 7: 97. pi. 9,f. 2. 1804. (Type from Long Island, New York.) Not C. tenuis J. F. Gmel. 1791.
"Carex debilis Michx." Boott, 111. Carex 92. pi. 272. 1860.
Carex debilis var. P Boott, 111. Carex 93. pi. 273. 1860. (Type from Penn Yan, New York.)
Carex debilis var. Rudgei L. H. Bailey, Mem. Torrey Club 1 : 34. 1889. (Based on C. tenuis Rudge.)
Carex debilis var. strictior L. H. Bailey, Mem. Torrey Club 1 : 34. 1889. (Type from White Mountains, New Hampshire.)
Carex debilis var. inlerjecta L. H. Bailey, Bull. Torrey Club 20: 418. 1893. (Based on C. debilis var. Boott.)
Carex tenuis var. inlerjecta Britton; Britt. & Brown, 111. Fl. 1 : 320. 1896. (Based on C. debilis var. interjecla Bailey.)
Carex tenuis var. erectior Britton; Britt. & Brown, 111. Fl. 1: 321. 1896. (New name for C. debilis var. strictior Bailey, not C. strictior Dewey, 1846.) Cespitose, not stoloniferous, the rootstocks very short, the clumps medium-sized or large, the culms 2-10 dm. high, slender but erect, exceeding the leaves, mostly lateral and aphyllopodic, a few central and phyllopodic, sharply triangular, somewhat roughened on the angles above, reddish-purple at base, the basal sheaths breaking and becoming somewhat filamentose ; sterile shoots conspicuous, phyllopodic or nearly so, mostly elongate; culm-leaves usually 2 or 3 and with the bracts evenly distributed, not bunched, their blades flat, deep-green, not stiff, ascending, 7-30 cm. long, 2-4 mm. wide, roughened on the margins and toward the apex, long-acuminate, the blades of the shoots up to 4.5 dm. long, 2.5-4 mm. wide; sheaths thin, yellowish-brown-tinged and reddish-dotted ventrally, glabrous, concave at mouth, the ligule longer than wide; staminate spike solitary, slender-peduncled, narrowly linear, 1.5-5 cm. long, 1 mm. wide, often with some perigynia at the summit, the scales loosely appressed, oblong-obovate, obtuse or acutish, whitish-straw-colored and more or less yellowish-browntinged, with green, 3-nerved, little roughened or nearly smooth center; pistillate spikes usually 3 or 4, not approximate except the uppermost, on slender rough peduncles, from twice the length of to shorter than the spikes, the spikes nodding to weakly erect, elongate, narrowly linear, 2-8 cm. long, 3-4 mm. wide, 12-25-flowered, the perigynia ascending, overlapping above, loosely flowered at base or sometimes throughout, the rachis flexuose, terminating in an empty scale; bracts usually exceeding the culms, the lowest leaf-like, with sheaths 1-4 cm. long, smooth, the upper much reduced; scales obovate, oblong-obovate, or ovate, obtuse to short-acuminate, narrower than and from one third to three fourths the length of the perigynia, more or less ciliate, greenish-white with green, 3-nerved, smooth or little roughened center, and more or less strongly reddish-brown-tinged, the midvein very prominent, not reaching top, sharply keeled, the scales at top not closely appressed, mostly deciduous with or after the perigynia; perigynia lanceolate, 4.5-7 mm. long, 1.75-2.25 mm. wide, triangular in crosssection, little inflated, glabrous but obscurely or slightly roughened on angles, membranaceous, deep-green, 2-ridged and slenderly several-nerved, round-tapering at base and truncately substipitate, contracted at apex into a yellowishbrown-tinged, rough, obliquely strongly bidentate, stoutish beak, the tip not enlarged, about 1 mm. long, ciliate and white-hyaline between the teeth; achenes obovoid, 2 mm. long, 1.5 mm. wide, triangular with sides concave below and thickened angles, in lower half of perigynium, slenderly stipitate, slenderly apiculate, jointed with the flexuose slender style; stigmas 3, slender, short, brownish-black.
Type locality: "Habitat in Pensylvania."
Distribution: Dry woods, acid soils, Newfoundland to Wisconsin, and southward to Virginia and Missouri, and in the mountains to North Carolina and Tennessee. (Specimens examined from Newfoundland, Quebec, Prince Edward Island, New Brunswick, Nova Scotia, Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Pennsylvania, Delaware, Maryland, West Virginia, Virginia, North Carolina, Kentucky, Tennessee, Ohio, Michigan, Indiana, Wisconsin, Missouri.)

Carex allegheniensis Mackenzie, sp. nov
Carex venusta var. Boott, 111. Carex 51. 1858. (Type from North Carolina.) Carex debilis var. pubera A. Gray, Man. ed. 5. 593. 1867.
Cespitose, not stoloniferous, the rootstock very short, the clumps medium-sized or large, the culms 2.5-6 dm. high, slender but erect, exceeding the leaves, lateral and aphyllopodic or central and phyllopodic, sharply triangular, smooth or but slightly roughened on the angles above, reddish-purple at base, the basal sheaths breaking and becoming somewhat filamentose; sterile shoots aphyllopodic, conspicuous, mostly elongate; leaves with well-developed blades 2-4 to a fertile culm, not bunched, the blades flat, not stiff, pale-green, very sparingly hirsute on upper surface at base, 7-30 cm. long or even longer on the sterile shoots, 2-3 mm. wide, long-acuminate, much roughened toward the apex, the sheaths thin, yellowish-brown-tinged and reddish-dotted ventrally, smooth dorsally, concave at mouth, the ligule longer than wide; terminal spike staminate, more or less strongly peduncled, very narrowly linear, 1.5-3 cm. long, 1 mm. wide, the scales loose, oblong-obovate or oblanceolate, ciliate, white-hyaline with conspicuously roughened, sharply defined, green midrib extending to the acute or acuminate tip; pistillate spikes 2-4, not approximate or the upper slightly so, drooping or weakly erect on rough slender peduncles from much shorter than to 3 times the length of the spikes, the spikes narrowly linear, 2.5-5 cm. long, 3-4 mm. wide, with 8-20 appressed-ascending perigynia overlapping in few rows, or often loosely flowered at base, the rachis flexuose, terminating in empty scales; lower bracts leaflet-like, the upper reduced, but usually exceeding inflorescence, the sheaths 1-4 cm. long, smooth; scales oblanceolate or oblong-obovate, slightly narrower than and from one third to one half the length of the perigynia, sharply keeled, cuspidate or awned, more or less ciliate, little or not at all brownish-tinged, white-hyaline with roughish green midvein extending to tip, somewhat persistent after fall of perigynia ; perigynia lanceolate, 5-7 mm. long, 1.5 mm. wide, obscurely triangular in cross-section, but little inflated, hirsutulous, membranaceous, light-green, or greenish-straw-colored at maturity, 2-keeled and slenderly several-nerved, tapering at base, short-stipitate, tapering at apex into a slender, unequally cleft, sharply bidentate beak 1 mm. long, the teeth ciliate; achenes elliptic or oblong-ovoid, 1.75-2 mm. long, 1-1.25 mm. wide, in lower half of perigynium, triangular with sides concave below and thickened angles, punctate, yellowish, sessile or substipitate, strongly slenderly apiculate, jointed with the nearly straight slender style; stigmas 3, slender, rather long, reddishbrown.
Typr locality (of C. debilis var. pubera Gray, on which C. allegheniensis is based): "Bear Meadows, Centre County, Penn., Prof. Porter."
Distribution: Dry woodlands, mostly in the mountains, Pennsylvania to North Carolina. (Specimens examined from Pennsylvania, District of Columbia, Virginia, North Carolina.)

Carex flexuosa, commonly called flexuous white-edge sedge, or Rudge's white-edge sedge, is a species of flowering plant in the sedge family, Cyperaceae. It is native to the eastern North America, where it is found in eastern Canada, the northeastern and midwestern United States, and southward in the Appalachian Mountains. Its natural habitat is in upland forests, rock outcrops, and Appalachian balds. It is typically found in areas with acidic soil.

Carex flexuosa is a clumping perennial. It is similar to Carex debilis, of which it is frequently considered a variety, as Carex debilis var. rudgei. Carex flexuosa can be distinguished from C. debilis by its smaller perigynia that are broadest near the middle. It is also similar to Carex allegheniensis, from which Carex flexuosa can be distinguished by its glabrous (hairless) perigynia.