43. Boechera hoffmannii (Munz) Al-Shehbaz, Novon. 13: 386. 2003. (as hoffmanii).
Arabis maxima Greene var. hoffmannii Munz, Bull. S. Calif. Acad. Sci. 31: 63. 1932; A. hoffmannii (Munz) Rollins
Perennials; long-lived; sexual; caudex woody (sometimes with persistent, crowded leaf bases). Stems usually 1 per caudex branch, arising from center of rosette, often elevated above ground surface on woody base, 5-7 dm, glabrous or sparsely pubescent proximally, trichomes short-stalked, 2- or 3-rayed, 0.15-0.4 mm, glabrous or sparsely pubescent distally. Basal leaves: blade narrowly oblanceolate, 3-8 mm wide, margins coarsely dentate, ciliate, trichomes (simple and 2-rayed), to 0.6 mm, surfaces sparsely to densely pubescent, trichomes short-stalked, 2-7-rayed, 0.15-0.4 mm. Cauline leaves: 15-65, concealing stem; blade auricles 1-4 mm, surfaces of distalmost leaves pubescent. Racemes 30-70-flowered, sometimes branched. Fruiting pedicels divaricate-ascending, straight, 10-45 mm, glabrous. Flowers ascending at anthesis; sepals pubescent; petals white or pale lavender, 8-10 × 1.5-2 mm, glabrous; pollen ellipsoid. Fruits divaricate-ascending to horizontal, not appressed to rachis, not secund, usually curved, rarely straight, edges parallel, 6-10 cm × 2.5-3 mm; valves glabrous; ovules 170-220 per ovary; style 0.05-0.5 mm. Seeds biseriate, 1.2-1.6 × 0.9-1.2 mm; wing continuous, 0.1-0.2 mm wide.
Flowering Feb-Mar. Sea cliff ledges and crevices of volcanic outcrop in chaparral communities; of conservation concern; 0-100 m; Calif.
Boechera hoffmannii is a distinctive sexual species that appears to be restricted to Santa Cruz Island in Santa Barbara County. It is in the Center for Plant Conservation’s National Collection of Endangered Plants.