259.
Carex
hendersonii
L. H. Bailey, Proc. Amer. Acad. Arts. 22: 115. 1887 (as hendersoni).
Culms densely tufted, ascending, lax or decumbent, 45—87 cm × 2—2.2 mm brownish. Leaves: basal sheaths; sheaths green, lighter toward base, 7—55 mm; blades ascending, green, corrugate, 19—52 cm × 3—16 mm, blades of overwintering leaves smooth abaxially. Inflorescences: peduncles of lateral spikes 0—15 cm; of terminal spike 0.2—4 cm; bracts 2.5—13 × 3—10 mm, blade of distal lateral spike linear. Spikes (3—)4(—5) per culm; lateral spikes erect, 12—27 × 2.7—3 mm; terminal spike linear-clavate, 15—21 × 2—2.7 mm, usually from sheath of distal lateral spike. Pistillate scales 2.7—3.1 × 1.9—2.3 mm, apex aristate to acute. Staminate scales obovate, 5.7—6.2 × 2.7—3 mm, margins hyaline and brownish, apex acute. Anthers 3—3.2 mm. Perigynia 7—12 per spike, scattered on proximal spikes, ratio of longer lateral spike length to perigynia number 1.9—3.4, aggregated on distal spikes, (22—)25—32-veined, linear, 4.6—6 × 1.8—2.3 mm; beak slightly concave at maturity, 0.5—1.8 mm. Achenes ellipsoid, 4.5—5 × 1.6—2 mm.
Fruiting spring—summer. Moist, mixed deciduous-evergreen forests; 5—1000 m; B.C.; Calif., Idaho, Oreg., Wash.
