96. Boechera shockleyi (Munz) Dorn, Brittonia. 55: 3. 2003.
Arabis shockleyi Munz, Bull. S. Calif. Acad. Sci. 31: 62. 1932
Perennials; usually short-lived; sexual; caudex not woody, (rarely with persistent, crowded leaf bases). Stems usually 1 per caudex branch, arising from center of rosette near ground surface, (0.8-)2-5 dm, densely pubescent proximally, trichomes short-stalked, 7-12-rayed, 0.1-0.2 mm, densely to sparsely pubescent distally. Basal leaves: blade oblanceolate, 3-10 mm wide, margins entire, not ciliate, surfaces densely pubescent, trichomes short-stalked, 7-12-rayed, 0.1-0.2 mm. Cauline leaves: 14-60, concealing stem for most of length; blade auricles 0.5-4 mm, surfaces of distalmost leaves densely pubescent. Racemes 20-70-flowered, usually unbranched. Fruiting pedicels divaricate-ascending, straight, 7-28 mm, pubescent, trichomes appressed, branched. Flowers ascending at anthesis; sepals pubescent; petals lavender, 6-9 × 0.8-1.2 mm, glabrous; pollen ellipsoid. Fruits divaricate-ascending, not appressed to rachis, not secund, usually curved, rarely straight, edges parallel, 4.5-11 cm × 1.5-2 mm; valves glabrous or sparsely pubescent throughout; ovules 140-190 per ovary; style 0.05-0.6 mm. Seeds sub-biseriate, 1-1.3 × 0.7-0.8 mm; wing distal or, rarely, absent, 0.05-0.1 mm wide.
Flowering Apr-May. Rock outcrops (primarily dolomite) and gravelly soil in desert scrub, sagebrush, and pinyon-juniper woodlands; 1200-2200 m; Calif., Nev., Utah.
Boechera shockleyi is a distinctive sexual species recognizable by the combination of strongly overlapping cauline leaves, a dense covering of minute, 7-12-rayed trichomes, and relatively long, curved, divaricate-ascending fruits with sub-biseriate seeds. It is most similar to B. inyoensis, but differs from that species in its narrower (0.8-1.2 versus 1.2-2 mm) petals, eciliate basal leaves with smaller (0.1-0.2 versus 0.2-0.7 mm) trichomes, greater number (140-190 versus 74-134) of ovules per ovary, and shorter (1-1.3 versus 1.7-2 mm) seeds with distal (versus continuous) wings.