Boechera drepanoloba

Perennials; short- to long-lived; apomictic; caudex usually not woody. Stems usually 1 per caudex branch, arising from center of rosette near ground surface, 1–4 dm, glabrous or sparsely pubescent proximally, trichomes sessile or subsessile, 2- or 3-rayed, 0.1–0.3 mm, glabrous distally. Basal leaves: blade oblanceolate, 2–6 mm wide, margins entire, ciliate along petiole, trichomes (submalpighiaceous or simple), to 0.6 mm, surfaces sparsely to densely pubescent, trichomes subsessile, 2–6-rayed, 0.1–0.3 mm. Cauline leaves: 3–15, often concealing stem proximally; blade auricles 0.7–2.5 mm, surfaces of distalmost leaves usually glabrous. Racemes 5–25-flowered, usually unbranched. Fruiting pedicels horizontal to ascending, straight or curved, 4–8 mm, glabrous. Flowers ascending at anthesis; sepals glabrous or pubescent with scattered trichomes; petals purple to lavender, 6–8 × 1.5–2.5 mm, glabrous; pollen spheroid. Fruits horizontal to ascending, secund, straight to slightly curved, edges parallel, 3–5.8 cm × 2–3.5 mm; valves glabrous; ovules 44–76(–104) per ovary; style 0.05–0.5 mm. Seeds uniseriate, 1.5–2.2 × 1.2–1.6 mm; wing continuous, 0.3–0.7 mm wide.

Phenology: Flowering Jul–Aug.
Habitat: Rocky slopes and talus in alpine and subalpine habitats
Elevation: 2000-3800 m

Distribution

• Generated Map
• Legacy Map

Alta., Alaska, Colo., Idaho, Mont., Oreg., Utah, Wash., Wyo.

Discussion

Morphological evidence suggests that Boechera drepanoloba is an apomictic species that arose through hybridization between B. lemmonii and B. stricta (see M. D. Windham and I. A. Al-Shehbaz 2007 for detailed comparison).

Selected References

None.

Lower Taxa

None.