Arabis holboellii Hornemann var. fendleri S. Watson in A. Gray et al., Syn. Fl. N. Amer. 1(1,1): 164. 1895; A. fendleri (S. Watson) Greene

Perennials; short- to long-lived; sexual; caudex usually not woody (sometimes with persistent, crowded leaf bases). Stems 1-7 per caudex branch, arising from center of rosette near ground surface, or arising laterally proximal to sterile shoots, 1.5-5.5(-8) dm, densely pubescent proximally, trichomes simple and long-stalked, 2-rayed, 0.2-0.9 mm, glabrous distally. Basal leaves: blade broadly oblanceolate, 5-15(-20) mm wide, margins dentate, ciliate, trichomes (simple), to 1.2 mm, surfaces glabrous or pubescent, trichomes simple and long-stalked, usually 2-rayed, rarely some 3-rayed, 0.2-0.6 mm. Cauline leaves: 8-25, often concealing stem proximally; blade auricles 0.8-3 mm, surfaces of distalmost leaves often glabrous. Racemes 6-40(-74)-flowered, usually unbranched. Fruiting pedicels horizontal to divaricate-ascending, curved or angled downward, 9-18(-23) mm, usually glabrous, rarely sparsely pubescent, trichomes spreading, simple. Flowers ascending at anthesis; sepals sparsely hirsute; petals usually lavender, rarely white, 5-9 × 1-2 mm; pollen ellipsoid. Fruits widely pendent, not appressed to rachis, not secund, curved to nearly straight, edges parallel, 3-5.8 cm × 1.5-2 mm; valves glabrous; ovules 98-128 per ovary; style 0.2-0.5 mm. Seeds biseriate, 0.9-1.2 x 0.6-0.8 mm; wing distal (sometimes absent), 0.05-0.15 mm wide. 2n = 14.

Flowering Apr-Jul. Rocky slopes in pine forests, pinyon-juniper woodlands, scrub oak; 1800-2800 m; Ariz., Colo., Nev., N.Mex., Utah.

As circumscribed by R. C. Rollins (1993), Boechera fendleri included distinctive elements, segregated here as B. porphyrea, B. spatifolia, and B. texana (see M. D. Windham and I. A. Al-Shehbaz 2006, 2007 for detailed comparison). Boechera fendleri in the strict sense is a sexual diploid extending from the Four Corners region through northern Arizona to southern Nevada.