Carex rossii

Plants densely cespitose; rhizomes usually ascending, occasionally horizontally spreading, dark reddish brown to purplish brown, 0-10 mm, stout. Culms ascending, 7-30(-40) cm, weakly to strongly scabrous distally; bases (remnants of old leaves) slightly fibrous. Leaf blades pale to dark green, usually equaling or exceeding stems, occasionally shorter, 0.8-2.5(-4) mm wide, herbaceous, glabrous abaxially, strongly scabrous to papillose adaxially. Inflorescences with both staminate and pistillate spikes; peduncles of basal pistillate spikes erect, elongate, slender; peduncles of staminate spikes 1.1-10 mm; proximal nonbasal bracts leaflike, exceeding inflorescences. Spikes: proximal pistillate spikes 2-4 (basal spikes 1-2); cauline spikes overlapping or somewhat separated, with 3-10(-15) perigynia; staminate spikes (4.8-)6-12.8 × (0.7-) 0.9-1.3(-2.5) mm. Scales: pistillate scales pale to dark reddish brown, with narrow white margins, ovate, 2.9-5.7 × 1.4-2.3 mm, shorter than perigynia, apex acute or acuminate to long-acuminate; staminate scales lanceolate, 3.2-5.8 × 1.2-1.8 mm, apex acuminate. Anthers 1.2-2 mm. Perigynia green to pale brown, veinless, ellipsoid to obovoid, 3.1-4.5 × 1.4-1.7 mm; beak straight or slightly bent, pale green, occasionally with reddish brown tinge, 0.9-1.7 mm, ciliate-serrulate, apical teeth 0.2-0.4 mm. Stigmas 3. Achenes brown, globose to obovoid or ellipsoid, obtusely trigonous in cross section, 1.9-2.4 × 1.3-1.7 mm. 2n = 36.

Fruiting mid Apr-early Sep. Moist or dry, sandy or rocky, open montane pine, fir, and spruce woodlands, sagebrush slopes, deciduous wooded slopes, prairies, alpine meadows; 210-3700 m; Alta., B.C., Man., N.W.T., Ont., Sask., Yukon; Alaska, Ariz., Calif., Colo., Idaho, Mich., Minn., Mont., Nebr., Nev., N.Mex., Oreg., S.Dak., Utah, Wash., Wyo.

Much like no. 101 [Carex deflexa Hornem.], but more densely cespitose, without creeping rhizomes; stems 1-3 dm; staminate spike longer, 5-12(-15) mm; perigynium 3-4.5 mm, its beak 1-1.7 mm, half to fully as long as the body, often strongly bidentate with teeth to 0.6 mm; 2n=36. Dry, rocky, exposed places; Yukon to Calif. and Colo., e. irregularly to Minn. and to Keweenaw Point, Mich.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

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