Boechera subpinnatifida |
Boechera breweri |
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ashy rock-cress, Klamath rockcress |
Brewer's rock-cress |
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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 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. |
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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, 3–7(–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. |
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Cauline leaves | (10–)20–60, often concealing stem throughout; blade auricles 0.5–3 mm, surfaces of distalmost leaves moderately to sparsely pubescent. |
5–15(–28), often concealing stem proximally; blade auricles 0.5–3(–5) mm, surfaces of distalmost leaves pubescent. |
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Racemes | 8–30-flowered, usually unbranched. |
7–20(–30)-flowered, usually unbranched. |
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Flowers | divaricate-ascending to pendent at anthesis; sepals pubescent; petals usually purple, rarely lavender, 9–14 × 1.5–3 mm, glabrous; pollen ellipsoid. |
ascending at anthesis; sepals pubescent; petals usually purple (rarely lavender), 7–12 × 2–4 mm, glabrous; pollen ellipsoid. |
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Fruiting pedicels | reflexed, strongly recurved, 5–15 mm, pubescent, trichomes appressed, branched. |
ascending to divaricate-ascending, straight, 3–25 mm, pubescent or glabrous, trichomes spreading, simple and 2-rayed. |
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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. |
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. |
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Seeds | uniseriate, 2.5–3.5 × 1.5–2.2 mm; wing continuous or at both ends, 0.4–0.8 mm wide. |
uniseriate, 1.2–1.7 × 1–1.2 mm; wing continuous, 0.1–0.2 mm wide distally. |
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2n | = 14. |
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Boechera subpinnatifida |
Boechera breweri |
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Phenology | Flowering Mar–May. | |||||
Habitat | Rock outcrops, talus, gravelly soil, often in sagebrush-grassland communities | |||||
Elevation | 800-2400 m (2600-7900 ft) | |||||
Distribution |
CA; ID; NV; OR; UT
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CA; OR
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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.) |
Subspecies 2 (2 in the flora). Relatively few other sexual diploid species of Boechera co-occur with B. breweri, and the only currently recognized hybrid involving this taxon is B. rubicundula (= B. arcuata × B. breweri; M. D. Windham and I. A. Al-Shehbaz 2007). Boechera breweri appears to be related to B. sparsiflora, and some specimens of subsp. shastaensis can be difficult to separate from that species. The two subspecies appear to intergrade on the western side of the Sacramento Valley from Tehama to Solano counties. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 7, p. 409. | FNA vol. 7, p. 367. | ||||
Parent taxa | ||||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Arabis subpinnatifida | Arabis breweri, Arabis breweri var. figularis, Arabis epilobioides | ||||
Name authority | (S. Watson) Al-Shehbaz: Novon 13: 389. (2003) | (S. Watson) Al-Shehbaz: Novon 13: 384. (2003) | ||||
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