5. Boechera breweri (S. Watson) Al-Shehbaz, Novon. 13: 384. 2003.
Arabis breweri S. Watson, Proc. Amer. Acad. Arts 11: 123. 1876; A. breweri var. figularis Jepson; A. epilobioides Greene
Perennials; long-lived; sexual; caudex woody. Stems usually 1 per caudex branch, arising from center of rosette, somewhat elevated on woody base or from ground surface, 0.6-3.5(-4.5) dm, densely pubescent proximally, trichomes long-stalked and simple, 2-rayed (sometimes all simple), 0.4-1 mm, sparsely pubescent or glabrous distally. Basal leaves: blade oblanceolate, 3-7(-11) mm wide, margins entire or dentate, ciliate proximally, trichomes to 1 mm, surfaces densely pubescent, trichomes long-stalked, 2-4-rayed, 0.4-0.8 mm. Cauline leaves: 5-15(-28), often concealing stem proximally; blade auricles 0.5-3(-5) mm, surfaces of distalmost leaves pubescent. Racemes 7-20(-30)-flowered, usually unbranched. Fruiting pedicels ascending to divaricate-ascending, straight, 3-25 mm, pubescent or glabrous, trichomes spreading, simple and 2-rayed. Flowers ascending at anthesis; sepals pubescent; petals usually purple (rarely lavender), 7-12 × 2-4 mm, glabrous; pollen ellipsoid. Fruits ascending to divaricate-ascending, not appressed to rachis, not secund, usually curved, rarely straight, edges parallel, 3.5-10 cm × 1.5-2.2 mm; valves usually glabrous, rarely sparsely pubescent; ovules 48-96 per ovary; style 0.05-0.3 mm. Seeds uniseriate, 1.2-1.7 × 1-1.2 mm; wing continuous, 0.1-0.2 mm wide distally.
Subspecies 2 (2 in the flora): w United States.