Boechera subpinnatifida |
Boechera rollinsiorum |
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ashy rock-cress, Klamath rockcress |
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Habit | Perennials; long-lived; sexual; caudex woody (often with persistent, crowded leaf bases). | Perennials; long-lived; sexual; caudex woody. |
Stems | usually 1 per caudex branch, arising from center of rosette near ground surface, 1–4(–5) dm, densely pubescent proximally, trichomes short-stalked, 2–6-rayed, 0.1–0.2 mm, sparsely pubescent distally. |
usually 3–5 per caudex branch, arising from margin of rosette, elevated above ground surface on woody base, 1–2.5 dm, densely pubescent proximally, trichomes short-stalked, 2–4 (or 5)-rayed, 0.2–0.4 mm, moderately to sparsely pubescent distally. |
Basal leaves | blade narrowly oblanceolate, 1–4(–5) mm wide, margins prominently dentate to subpinnatifid (leaf margins of sterile shoots often entire), ciliate near petiole base, trichomes (simple or 2-rayed), 0.4–0.6 mm, surfaces densely pubescent, trichomes short-stalked, (2–)4–9-rayed, 0.05–0.2 mm. |
blade oblanceolate, 3–5 mm wide, margins entire, ciliate proximally, trichomes (simple), to 0.6 mm, surfaces densely pubescent, trichomes short-stalked, 2–4 (or 5)-rayed, 0.15–0.4 mm. |
Cauline leaves | (10–)20–60, often concealing stem throughout; blade auricles 0.5–3 mm, surfaces of distalmost leaves moderately to sparsely pubescent. |
5–9, not concealing stem; blade auricles 0.5–1 mm, surfaces of distalmost leaves sparsely to moderately pubescent. |
Racemes | 8–30-flowered, usually unbranched. |
5–11-flowered, usually unbranched. |
Flowers | divaricate-ascending to pendent at anthesis; sepals pubescent; petals usually purple, rarely lavender, 9–14 × 1.5–3 mm, glabrous; pollen ellipsoid. |
divaricate-ascending at anthesis; sepals pubescent; petals pale purple, 6–8 × 1.5–2 mm, glabrous; pollen ellipsoid. |
Fruiting pedicels | reflexed, strongly recurved, 5–15 mm, pubescent, trichomes appressed, branched. |
descending, straight to slightly recurved, 4–6 mm, pubescent, trichomes appressed, branched. |
Fruits | pendent, not appressed to rachis, not secund, straight to slightly curved, edges parallel, (3.5–)5–8 cm × (1.6–)2–3 mm; valves pubescent throughout; ovules 24–42 per ovary; style 0.5–1 mm. |
(immature) pendent, not appressed to rachis, not secund, straight, edges parallel; valves glabrous. |
Seeds | uniseriate, 2.5–3.5 × 1.5–2.2 mm; wing continuous or at both ends, 0.4–0.8 mm wide. |
not seen. |
2n | = 14. |
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Boechera subpinnatifida |
Boechera rollinsiorum |
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Phenology | Flowering Mar–May. | Flowering Jun. |
Habitat | Rock outcrops, talus, gravelly soil, often in sagebrush-grassland communities | Metamorphosed igneous gravel on steep slopes |
Elevation | 800-2400 m (2600-7900 ft) | ca. 2100 m (ca. 6900 ft) |
Distribution |
CA; ID; NV; OR; UT
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ID |
Discussion | Originally thought to be restricted to northern California and adjacent Oregon, Boechera subpinnatifida is a sexual species that recently has been found in central Idaho, northern Nevada, and northwestern Utah. It appears to intergrade with both B. puberula and B. retrofracta, and species boundaries within this complex need further study. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Boechera rollinsiorum shows superficial similarities to both B. glareosa and B. lasiocarpa (see M. D. Windham and I. A. Al-Shehbaz 2006 for detailed comparison). It is known thus far only from the type collection below Galena Summit in central Idaho. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 409. | FNA vol. 7, p. 403. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Arabis subpinnatifida | |
Name authority | (S. Watson) Al-Shehbaz: Novon 13: 389. (2003) | Windham & Al-Shehbaz: Harvard Pap. Bot. 11: 81. (2006) |
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