Dunhead Sedge

Reports of Carex phaeocephala from northern Canada are based on other species, mostly C. tahoensis.

Plants densely cespitose. Culms (5–)15–45 cm. Leaves: sheaths adaxially white-hyaline, summits U-shaped or rounded, often prolonged to 2.5(–3) mm beyond collar; distal ligules 1.5–2.5(–3) mm; blades 3–5 per fertile culm, often channeled, occasionally folded, becoming trigonous toward tip, 5–20 cm × 1–2.5(–3) mm, if not folded, margins revolute. Inflorescences usually dense, stiff, gold to brown or brown and green, 1.5–3.5(–4) cm × 10–15 mm; proximal internode 4–10 mm; 2d internode 2–5 mm; proximal bracts scalelike to bristlelike, shorter than inflorescences. Spikes (3–)4–7, distant, distinct, ovoid to broadly ovoid, 12–15 × 5.5–8 mm, base rounded to attenuate, apex acute to truncate. Pistillate scales gold or brown, usually with pale to green midstripe, lanceolate to ovate, 3.7–5.1 mm, usually ± equaling and covering perigynia, margin white-hyaline, 0.1–0.3 mm wide, apex acute to acuminate. Anthers early deciduous or short-persistent. Perigynia ascending, greenish or pale gold to brown, conspicuously (0–)4–9-veined abaxially, conspicuously 0(–4)-veined adaxially, narrowly ovate to broadly ovate, flat or plano-convex, 3.8–5.2 × 1.5–2.3 mm, 0.4–0.5 mm thick, margin flat, including wing 0.3–0.5 mm wide, ciliate-serulate at least on distal body, not crinkled, without glossy metallic sheen; beak brown to red-brown or gold with white-hyaline tip, cylindric, unwinged, ± entire for 0.6 mm, abaxial suture with conspicuous white margin, distance from beak tip to achene 1.8–2.2 mm. Achenes ovate to broadly ovate or, occasionally, elliptic, 1.5–2 × 0.8–1.1(–1.2) mm, 0.3–0.5 mm thick. 2n = 84.

Alta., B.C.; Alaska, Calif., Colo., Idaho, Mont., Nev., Oreg., Utah, Wash., Wyo.

Fruiting summer.

High-montane to alpine areas, usually rocky soils; 1200–4000m.

Carex phaeocephala Piper, Contr. U. S. Nat Herb. 11: 172. 1906.
Carex leporina var. americana Olney; (A. Gray, Proc. Am. Acad. 8: 407, name only. 1872) L. H.
Bailey. Proc. Am. Acad. 22: 152. 1886. (Type from Oregon.) "Carex leporina L." L. H. Bailey, in Coult. Man. 396. 1885. ■■Carex Preslii Steud." I. II Bailey. Mem. Torrey Club 1: 52. 1889. "Carex petasata Dewey" Holm, Am. Jour. Sci. IV. 16: 20. 1903. Carex petasata var. plciosiachya Kukcnth. in Engler, Pflanzenreich 4 20 : 210. 1909. (Type from
Lake Louise, Alberta.) Carex tahoensis Smiley, Univ. Calif. Publ. Bot. 9: 119. 1921. (Type from Mt. Tallac, Lake Tahoe.
California. )
Very densely cespitose, forming large stools, the rootstocks densely matted, very short, blackish, fibrillose, the culms 1-3 dm. high, slender but stiff, exceeding the leaves, obtusely triangular below, sharply angled and more or less roughened above, brownish at base, the dried-up leaves of the previous year conspicuous, the lower bladeless; leaves with well-developed blades 3-6 to a fertile culm, clustered towards the base, the blades short, canaliculate or more or less involute, ascending to recurving, usually 5-15 cm. long, 1.5-2 mm. wide, stiff, lightgreen, roughened towards the apex, the sheaths tight, white-hyaline ventrally, truncate at mouth, short prolonged beyond base of blade and continuous with ligule; sterile culm I similar; in (lore see in I 2-5, usually 3 or 4, rarely 7, spikes aggregated into an erect
head 12-25 mm. long. 5-12 mm. thick, tinlowei oni oi twospiki occasionally a little separate,
the spikes ovoid to oblong-obovoid, 6-12 mm. long, 5-8 mm. wide, gynaccaudrnii . obtl
apex, narrowed and often quite clavate ;ii ba • i pi daily the uppermoi I and hi no making
laminate portion more con ruling,
becoming loosely flowered at maturity, the bi much shorter than the head, occasionally developing a cuspidate point, the upper scale-like; scales ovate, acute, brownish-black or brownish or reddish-brown, with lighter 1-3-nerved center and broad white-hyaline margins, as long and as wide as and concealing the perigynia until over-ripe; perigynia concavo-convex, oblong-ovate or obovate, thin but distended over the achene, 4-6 mm. long, 1.75-2.5 mm. wide, membranaceous, slightly spongy at base, straw-colored to brownish-black, rather conspicuously margined, the margins green-winged to base, serrulate to below middle, substipitate, round-tapering at base, several-nerved dorsally, lightly several-nerved ventrally or nearly nerveless, abruptly contracted into a chestnut-brown beak 1 mm. long, serrulate below, terete, strongly white-hyaline-tipped and nearly smooth above, and obliquely cut dorsally, with white-hyaline margins; achenes lenticular, oblong-obovoid, 1.5 mm. long, 1 mm. wide, substipitate (nearly sessile), apiculate, brownish; style slender, jointed with achene, at length deciduous; stigmas two, reddish-brown, slender, elongate.
Tvpe locality (of C. leporina var. americana Olnev, on which C. phaeocephala is based) : Oregon (Elihu Hall 583).
Distribution : High mountain summits. Alberta to Colorado, westward to British Columbia, and southward to California, where confined to the higher peaks of the Sierra Nevada, extending as far south as Mt. Whitney. (Specimens examined from Alberta. Montana. Wyoming. Colorado, Utah, Idaho, Nevada. California. Oregon. Washington, British Columbia (including Vancouver Island).)

Carex phaeocephala is a species of sedge known by the common name dunhead sedge.