Draba ramosissima Desvaux, J. Bot. Agr. 3: 186. 1815. TYPE. U.S.A.

Alyssum dentatum Nuttall, Gen. N. Amer. Pl. 2: 63. 1818; D. dentata (Nuttall) W. J. Hooker & Arnott, J. Bot. (Hooker) 1: 192. 1834. TYPE. U.S.A. [[Harper’s Ferry at K]]            

Draba ramosissima var. glabrifolia E. L. Braun, Rhodora 42: 49. 1940. TYPE. U.S.A. Kentucky. Jessamine Co.: Brooklyn Bridge, edge of mossy cliff facing north, 17 Apr 1937, E. Lucy Braun s.n. (holotype, GH!; isotype, US!).

     Herbs perennial; caudex well developed, many branched, with persistent leaf bases. Stems single from caudex branches, 7–38(–5) cm, unbranched at base, paniculately branched above, pubescent proximally with short-stalked, 2–4-rayed trichomes 0.1–0.6 mm, these sometimes mixed with simple trichomes 0.4–0.8 mm. Basal leaves rosulate, oblanceolate, (0.7–)1–5.5 cm × 2–8 mm, dentate; both surfaces pubescent with short-stalked to subsessile, 3- or 4-rayed trichomes 0.1–0.5 mm; adaxial surfaces sometimes also with simple trichomes 0.4–1.3 mm; petiole to 2 cm, ciliate with simple trichomes 0.3–0.5 mm; cauline leaves of flowering stems (5–)7–15(–21), ovate to oblong or elliptic to lanceolate, coarsely dentate or serrate, rarely subpinnatifid, sessile, pubescent as basal leaves. Racemes ebracteate, paniculate, 9–28-flowered; rachis pubescent as stem, not flexuous; lowermost fruiting pedicels (4–)6–12(–15) mm, horizontal to divaricate-ascending, straight, pubescent with 2–4-rayed trichomes. Flowers: sepals oblong, 2.5–3 mm, with simple and subsessile, 2–4-rayed trichomes; petals white, spatulate, 4–6 × 1.5–2.5 mm; anthers oblong, 0.5–0.6 mm. Fruits narrowly oblong to elliptic or oblong-lanceolate, 5–11 × 1.5–2.2 mm, flattened, often strongly twisted, pubescent with subsessile or sessile, 2–4-rayed trichomes 0.07–0.3 mm; style (1–)1.5–3(–4) mm, sparsely pubescent; ovules and seeds 4–10(–12) per fruit. Seeds oblong, flattened, 1.2–1.8 × 0.6–0.9 mm, wingless. 2n = 16.

Flowering: Apr–Jun.

Habitat: limestone cliffs and outcrops, shale barrens, and rocky wooded areas.

Elevation: 0–1100 m.

Distribution: United States (District of Columbia, Kentucky, Maryland, North Carolina, Tennessee, Virgina, West Virginia).