6. Boechera burkii (Porter) Windham & Al-Shehbaz, Harvard Pap. Bot. 12: 237. 2007; Arabis laevigata Muhlenberg ex Willdenow var. burkii Porter, Bull. Torrey Bot. Club 17: 15. 1890; A. burkii (Porter) Small, Man. Fl. Southeast. U.S. 572. 1933. TYPE: United States, Pennsylvania. Franklin County: Mercerburg, 1852, Isaac Burk s.n. (holotype, PH!; Isotype: GH!).
Plants biennials, without evident caudices, lacking crowded, persistent leaf bases; sexual, with ellipsoid pollen. Stems usually 1 per plant, arising near ground surface from center of basal rosettes, (2–)3–7 dm, glabrous and often glaucous throughout. Leaves at stem bases oblanceolate to obovate, 4–10 mm wide, dentate, not ciliate, blade surfaces glabrous or sparsely pubescent subapically with simple trichomes 0.3–0.8 mm; cauline leaves 18–28, often concealing stem proximally, the uppermost glabrous, without auricles. Inflorescences mostly unbranched, 20–50-flowered; fruiting pedicels 4–12 mm, ascending to divaricate-ascending, usually straight, glabrous. Flowers ascending at anthesis; sepals glabrous; petals white, 3–5 ´ 0.5–0.7 mm, glabrous; ovules 64–80 per fruit. Fruits 5–10 cm ´ 1.5–1.8 mm, divaricate-ascending, not appressed to rachises, not secund, curved or rarely straight, with parallel edges, glabrous; style 0.2–0.6 mm. Seeds uniseriate, 1.5–1.8 ´ 1.2–1.4 mm; wing continuous, 0.3–0.5 mm wide distally.
Habitat: rocky areas, wooded slopes, and river banks.
Distribution: United States (Maryland, Pennsylvania, Tennessee, Virginia, West Virginia).
Reproductive mode: sexual diploid.