General: Evergreen dwarf subshrub, prostrate with a creeping or trailing habit, 0.1-1 m (0.3-3 ft) long, rooting at nodes; stems moderately to sparsely hairy and often glandular, becoming glabrous with maturity; flowering stems erect to ascending, mostly 1-15 cm long. Leaves: Opposite, simple, elliptic to obovate or orbicular, 0.5-2 cm long, 0.3-1.5 cm wide, light green to yellowish green, glabrous or somewhat long-hairy along veins and margins, margins slightly toothed above the middle or entire; petiole short, 0.2-0.4 cm. Flowers: Paired, nodding, borne on a long, forked peduncle subtended by 2 bracts; calyx lobes 5, lance-shaped, 2-5 mm long; corolla bell- to funnel-shaped, 5-lobed, 0.8-1.5 cm long, white, tinged with pink, pubescent within; stamens 4, of unequal lengths. Fruits: Indehiscent capsule, ovoid, 3-locular, 1.5-3 mm long, dry; seed 1. Ecology: Found in dense coniferous forests from 6,000-10,000 ft (1829-3048 m), flowers June-September. Distribution: Apache County (White Mountains), Coconino County (Kaibab Plateau); most of North America, circumpolar distribution. Notes: Twin-flower is killed by fire. It reproduces vegetatively by stolons, and seeds are dispersed by attaching to animals. Ethnobotany: Tribes from other regions use the mashed plant as a poultice for inflammation of limbs and for headache. Editor: Springer et al. 2011
Stems trailing and creeping, emitting numerous short, suberect, leafy branches to 10 cm, these with a slender terminal peduncle to 10 cm; lvs firm, short-petioled, broadly oval to obovate, 1-2 cm; fls nodding; cor pink to white, 10-15 mm, shallowly 5-lobed, flaring from near the top of the cal, hairy inside; 2n=32. Moist or dry woods and cold bogs; circumpolar, s. in Amer. to N.J., W.Va., n. Ind., Minn., and Calif. June-Aug. Our plants are var. longiflora Torr. (L. americana)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.