264.
Carex
laxiflora
Lamarck in J. Lamarck et al., Encycl. 3: 392. 1792.
Carex laxiflore
Carex laxiflora var. serrulata F. J. Hermann
Culms densely tufted, lateral or central, ascending or lax to decumbent, 39—47 cm × 0.8—2 mm. Leaves: basal sheaths light brown; sheaths 6—22 mm; blades ascending, midrib and 2 lateral veins developed, occasionally slightly corrugated, 19—25 cm × 5—26 mm, blades of overwintering leaves smooth or, rarely, sparsely papillose abaxially. Inflorescences: peduncles of proximal spikes erect, 0—3.4 cm, of lateral spikes 1.4—3.3(—5.3) times as long as spikes they subtend; of terminal spikes 1—2.2 cm. Bracts 7.2—17.5 cm × 2—8 mm, bract blade of distal lateral spikes linear, narrower than spikes, widest bract blade of distalmost lateral spike 0.5—3.4 mm wide. Spikes (3—)4 per culm; lateral spikes 9—33 × 3.2—4 mm; terminal spike linear to clavate, 23—24(—34) × 1.5—3 mm. Pistillate scales 2.5—3 × 1.2—1.5 mm, apex acute or apiculate. Staminate scales 3—3.5 × 1—1.5 mm, oblong-ovate, margins white-hyaline or brownish, apex obtuse or acute. Anthers 2.6—3 mm. Perigynia 3—20 per spike, usually separate, ratio of longer lateral spike length to perigynia number 1.9—3.4, ascending, conspicuously (22—)25—32-veined, (2.6—)3.2—4.1(—4.6) × 1.2—1.6 mm; beak straight, 0.5—1.4 mm. Achenes broadly ellipsoid, 1.8—2.2(—3.4) × 1—1.4 mm. 2n = 40.
Fruiting spring—early summer. Dry or moist, deciduous or mixed deciduous-evergreen forests, higher elevations southward; 0—1000 m; N.S., Ont., Que.; Ala., Ark., Conn., Del., Ga., Ill., Ind., Ky., Maine, Md., Mass., Mich., Miss., Mo., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., Tenn., Vt., Va., W.Va., Wis.
The Carex laxiflora complex contains a wide array of phenotypic variation and deserves further research. F. J. Hermann (1938) proposed the name C. laxiflora var. serrulata; however, among the numerous specimens of C. laxiflora we studied, the key characteristic of ciliate-serrulate bract-sheaths varied greatly.
