5. Boechera breweri (S. Waton) Al-Shehbaz, Novon 13: 384. 2003.
Plants long-lived perennials, with woody caudices, lacking crowded, persistent leaf bases; sexual, with ellipsoid pollen. Stems usually 1 per caudex branch, somewhat elevated on woody bases or produced at ground surface, arising from center of basal rosettes, 0.6–3.5(–4.5) dm, lower parts with many simple and long-stalked, 2-rayed (occasionally all simple) trichomes 0.4–1 mm, upper parts sparsely pubescent or glabrous. Leaves at stem bases oblanceolate, 3–7(–11) mm wide, entire or dentate, ciliate proximally with trichomes to 1 mm, blade surfaces densely pubescent with long-stalked, 2–4-rayed trichomes 0.4–0.8 mm; cauline leaves 5–15(–28), often concealing stem proximally, the uppermost pubescent, with auricles 0.5–3.0(–5.0) mm. Inflorescences mostly unbranched, 7–20(–30)-flowered; fruiting pedicels 3–25 mm, ascending to divaricate-ascending, straight, with spreading, simple and 2-rayed trichomes or glabrous. Flowers ascending at anthesis; sepals pubescent; petals purple or rarely lavender, 7–12 ´ 2–4 mm, glabrous; ovules 48–96 per fruit. Fruits 3.5–10.0 cm ´ 1.5–2.2 mm, ascending to divaricate-ascending, not appressed to rachises, not secund, curved or rarely straight, with parallel edges, glabrous or rarely sparsely pubescent; style 0.05–0.30 mm. Seeds uniseriate, 1.2–1.7 ´ 1.0–1.2 mm; wing continuous, 0.1–0.2 mm wide.
Habitat: rocky outcrops, ledges and talus, woodlands.
Elevation: 300–2250 m.
Distribution: United States (California, Oregon).
Reproductive mode: sexual diploid.
Two subspecies: United States (California, Oregon).