Herbs acaulescent; caudex branched. Flowering stems often leafy, 30-95 cm, glabrous or short stipitate-glandular. Leaves: petiole glabrous or short stipitate-glandular; blade (often variegated adaxially), broadly ovate to cordate, shallowly 5-lobed, 3-12 cm, base cordate or nearly truncate, lobes rounded to widely ovate, terminal lobes often elongated, margins dentate, apex acute or obtuse, surfaces glabrous or short stipitate-glandular, at least on veins. Inflorescences diffuse. Flowers: hypanthium strongly bilaterally symmetric, free 2.2-6.2 mm, green, gibbous-tubular, abruptly inflated distal to adnation to ovary, 6.6-12.6 mm, short stipitate-glandular; sepals inflexed (closing mouth of flower), darker green-tipped, equal, 2-3.7 mm, apex rounded; petals inflexed (closing mouth of flower), white, pink, or purple, spatulate, unlobed, 1.8-5.5 mm, margins often fimbriate; stamens 2.4 mm included to 0.7 mm exserted; styles included 1.3-5.3 mm, 1.5-2.5 mm, to 0.1 mm diam. Capsules ovoid, 5-13 mm, beaks divergent, not papillose. Seeds dark brown, ellipsoid, 0.5-0.9 mm. 2n = 14.
Flowering May-Jun. Rich, shaded woods and roadcuts over limestone substrates and outcroppings; 100-500 m; Ala., Ky., N.C., Tenn., Va., W.Va.
Heuchera longiflora is restricted to limestone outcroppings and is rare in all the states where it is found.
Plants 3-9 dm; scape with small and scale-like or larger and leaf-like bracts; petioles glabrous or minutely glandular-puberulent; lvs round-cordate, glabrous or nearly so, or short-hairy on the veins beneath, often white-mottled, 5-9-lobed, the teeth very broad and flat or barely rounded, mucronate; stems short-hirsute; infl lax, with herbaceous bracts; fls horizontal, distinctly oblique, 7-9 mm on the upper side, 3/4 as long on the lower; sep inflexed, closing the fl, rounded, 2-3.5 mm, separated by narrow sinuses; pet white to pink or purple, inflexed, spatulate, 2-5 mm, often fimbriate; stamens evidently included to barely exserted; styles included 1.5-3 mm (from the cal-tip) at anthesis; 2n=14. Rich woods on limestone substrate; mts. of e. Ky., s. W.Va., and sw. Va. to N.C. and Ala. May, June.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.