14. Rhynchospora alba (Linnaeus) Vahl, Enum. Pl. 2: 236. 1805 (as Rynchospora).
Rhynchospore blanc
Schoenus albus Linnaeus, Sp. Pl. 1: 44. 1753; Dichromena alba (Linnaeus) J. F. Macbride; Phaeocephalum album (Linnaeus) House; Rhynchospora luguillensis Britton; Triodon albus (Linnaeus) Farwell
Plants perennial, densely cespitose, 6–75 cm; rhizomes mostly absent. Culms erect to curved, leafy, obscurely trigonous to nearly terete, few ribbed, slender. Principal leaves mostly overtopped by culm; blades narrowly linear to filiform, proximally flat, 0.5–1.5 mm, apex tapering, trigonous. Inflorescences: clusters 1 or 2–3, then widely spaced, narrowly turbinate to hemispheric, 1.5–2.5 cm wide; subtending leafy bracts often exceeded by distal cluster. Spikelets pale brown to nearly white, ellipsoid, 3.5–5.5 mm, apex acute; fertile scales elliptic, 3–3.5(–4) mm, apex acute or acuminate, midrib excurrent as mucro. Flowers: perianth bristles 10–12, slightly overtopping tubercle, retrorsely barbellate or rarely smooth, base often setose. Fruits 1(–2) per spikelet, (2.3–)2.5–3 mm; body pale brown with paler center, stipitate obovoid, lenticular, 1.5–1.8(–2) × 0.9–1.2 mm; surfaces transversely striate, relatively smooth, rim narrow, flowing to tubercle base; tubercle narrowly triangular subulate, 0.5–1.2 mm.
Fruiting summer–fall. Acid, sphagnous, boggy, open sites, poor fens, often on floating mats or peaty interstices of rocky shores; 0–2000 m; Alta., B.C., Man., N.B., Nfld. and Labr. (Nfld.), N.W.T., N.S., Ont., P.E.I., Que., Sask.; Alaska, Calif., Conn., Del., Fla.(?), Ga., Idaho, Ill., Ind., Maine, Md., Mass., Mich., Minn., N.H., N.J., N.Y., N.C., Ohio, Oreg., Pa., R.I., S.C., Tenn., Vt., Va., Wash., W.Va., Wis.; West Indies (Puerto Rico); South America(?); Eurasia.
The smooth-bristled Rhynchospora alba forma laeviseta Gale mostly occurs with the typical antrorsely barbellate type in Pennsylvania, the Great Lakes, British Columbia, Newfoundland, and Nova Scotia.