54. Boechera lemmonii (S. Watson) W. A. Weber, Phytologia 51: 370. 1982;Arabis lemmonii S. Watson, Proc. Amer. Acad. Arts 22: 467. 1887. TYPE: United States, California: Lassen Peak, Sep 1872, J. G. Lemmon 23 (lectotype designated by Rollins (1941: 383), GH!).
Arabis bracteolata Greene, Leafl. Bot. Observ. Crit. 2: 73. 1910. TYPE: United States, Wyoming, 31 Aug 1893, J. N. Rose 399a (holotype, US!).
Arabis canescens Nuttall var. latifolia S. Watson, Bot. U.S. Geol. Survey 40th Parallel 5: 17. 1871; Arabis latifolia (S. Watson) Piper, Contr. U.S. Natl. Herb. 11: 295. 1906. TYPE: United States, Nevada, Clover Mt., Sep 1868, 1100 ft, S. Watson 71 (lectotype designated by Rollins (1941: 383), GH!; isolectotype, NY!).
Arabis codyi G. A. Mulligan, Rhodora 97: 151. 1996. TYPE: Canada, Yukon, Kaskawulsh nunatak, jct. N and central arms Kaskawulsh Glaceier, W of Kluane Lake, 6000 ft., unstable slopes, 1 Jul-1 Aug 1965, D. F. Murray and D. B. Murray 72 (holotype, DAO!).
Arabis egglestonii Rydberg, Fl. Rocky Mts. 361. 1918. TYPE: United States, Colorado, Clover Mt, above Garfield, 3940 m, 31 Jul 1910, W. W. Eggleston 6013 (holotype, NY!; isotype, US!).
Arabis kennedyi Greene, Leaf. Bot. Observ. Crit. 2: 71. 1910. TYPE: United States, Nevada, Washoe Co., Galena Creek, Aug 1906, 8000 ft, P. B. Kennedy 1248 (holotype, US!; isotype, NY!).
Arabis oreocallis Greene, Leafl. Bot. Observ. Crit. 2: 73. 1910. TYPE: Canada, British Columbia, Selkirk and Rocky Mountains, [near 51°30˝N, Beaverfoot Mts],  Jul 1904, C. H. Shaw s.n. (holotype, US!; isotypes, E!, GH!, MO!, US!).
Arabis polyclada Greene, Leafl. Bot. Observ. Crit. 2: 75. 1910. TYPE: United States, California, Lassen Co., Farewell Gap, 10600 ft, Sep 1897, C. A. Purpus 5229 (holotype, US!; isotypes, E!, GH!, MO!, UC!).
Arabis semisepulta Greene, Leafl. Bot. Observ. Crit. 2: 74. 1910. TYPE: United States, Oregon: Mt Thielson, Cascade Mts, near summit, in loose lava gravel, 6 Aug 1897, F. V. Coville & E. I. Applegate 454 (holotype, US!; isotypes, DS!, RM!).
Plants long-lived, somewhat cespitose perennials, with woody caudices, lacking crowded, persistent leaf bases; sexual (with ellipsoid pollen) or apomictic (with spheroid pollen). Stems usually 1 per caudex branch, arising near ground surface from center of basal rosettes or laterally below sterile shoot, 0.5–2(–2.5) dm, lower parts glabrous or with scattered short-stalked, 2–6-rayed trichomes 0.1–0.2 mm, upper parts glabrous. Leaves at stem bases oblanceolate to obovate, 1.5–5.0 mm wide, entire or rarely slightly dentate, ciliate on petioles, blade surfaces densely to sparsely pubescent with short-stalked, 3–9-rayed trichomes 0.1–0.2 mm; cauline leaves 2–8(–12), not concealing stem, the uppermost glabrous or sparsely pubescent, with auricles 0.1–0.5 mm or lacking. Inflorescences mostly unbranched, 3–12(–17)-flowered; fruiting pedicels 2–6 mm, divaricate-ascending to slightly descending, slightly recurved or rarely straight, glabrous or with few appressed, branched trichomes. Flowers divaricate-ascending at anthesis; sepals glabrous or sparsely pubescent; petals purple to lavender, 3.5–6.0 ´ 1.0–1.5 mm; ovules and seeds 28–40(–44) per fruit. Fruits (1.6–)2.0–4.4 cm ´ 1.6–2.3 mm, divaricate-ascending to slightly descending, not appressed to rachises, secund, straight or curved, with parallel edges, glabrous; style 0.1–0.2 mm. Seeds uniseriate, 1.3–2.0 ´ 1.0–1.5 mm; wing continuous, 0.1–0.5 mm wide. 2n = 14.
Habitat: cliffs, talus slopes, and gravelly soil in alpine and subalpine habitats.
Elevation: 2150–4350 m.
Distribution: Canada (Alberta, British Columbia, Yukon), United States (Alaska, California, Colorado, Idaho, Montana, Nevada, Oregon, Utah, Washington, Wyoming).
Reproductive mode: sexual diploid, apomictic triploid.