Boechera subpinnatifida |
Boechera dentata |
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ashy rock-cress, Klamath rockcress |
Short's rockcress |
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Habit | Perennials; long-lived; sexual; caudex woody (often with persistent, crowded leaf bases). | Biennials; short-lived; sexual; caudex present or absent. |
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 2–4 per plant or caudex branch, arising from margin of rosette near ground surface, or arising laterally proximal to sterile shoots, 2–6 dm, pubescent proximally, trichomes short-stalked, 2–4-rayed, 0.15–0.4 mm, sparsely pubescent or glabrous 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 obovate to oblanceolate, (6–)10–45 mm wide, margins dentate, not ciliate, surfaces sparsely pubescent, abaxially trichomes short-stalked, 3- or 4-rayed, 0.15–0.4 mm, adaxially simple ones, 0.4–1 mm. |
Cauline leaves | (10–)20–60, often concealing stem throughout; blade auricles 0.5–3 mm, surfaces of distalmost leaves moderately to sparsely pubescent. |
4–20, rarely concealing stem; blade auricles 1–8 mm, surfaces of distalmost leaves sparsely pubescent. |
Racemes | 8–30-flowered, usually unbranched. |
14–66-flowered, sparingly branched. |
Flowers | divaricate-ascending to pendent at anthesis; sepals pubescent; petals usually purple, rarely lavender, 9–14 × 1.5–3 mm, glabrous; pollen ellipsoid. |
divaricate at anthesis; sepals glabrous or sparsely pubescent; petals white or cream, 2–3.5 × 0.7–1 mm, glabrous; pollen ellipsoid. |
Fruiting pedicels | reflexed, strongly recurved, 5–15 mm, pubescent, trichomes appressed, branched. |
divaricate-ascending to slightly descending, straight, 1–6 mm, glabrous or 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. |
divaricate-ascending to slightly descending, not appressed to rachis, not secund, straight or slightly curved, edges parallel, 1.3–4.2 cm × 0.7–0.8 mm; valves usually sparsely pubescent throughout, rarely glabrous; ovules 14–44 per ovary; style 0.1–0.5 mm. |
Seeds | uniseriate, 2.5–3.5 × 1.5–2.2 mm; wing continuous or at both ends, 0.4–0.8 mm wide. |
uniseriate, 0.7–1.1 × 0.5–0.6 mm; not winged. |
2n | = 14. |
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Boechera subpinnatifida |
Boechera dentata |
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Phenology | Flowering Mar–May. | Flowering Apr–Jun. |
Habitat | Rock outcrops, talus, gravelly soil, often in sagebrush-grassland communities | Bluffs and rocky ledges, wooded slopes, floodplains |
Elevation | 800-2400 m (2600-7900 ft) | 100-300 m (300-1000 ft) |
Distribution |
CA; ID; NV; OR; UT
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AL; AR; DC; IA; IL; IN; KS; KY; MD; MI; MN; MO; NE; NY; OH; OK; PA; SD; TN; VA; WI; WV; ON
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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.) |
Sisymbrium dentatum Torrey is an illegitimate name that pertains to Iodanthus dentatus. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 409. | FNA vol. 7, p. 373. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Arabis subpinnatifida | Shortia dentata, Arabis dentata var. phalacrocarpa, Arabis perstellata var. shortii, Arabis shortii, Arabis shortii var. phalacrocarpa, B. shortii, Iodanthus dentatus |
Name authority | (S. Watson) Al-Shehbaz: Novon 13: 389. (2003) | (Rafinesque) Al-Shehbaz & Zarucchi: Harvard Pap. Bot. 13: 293. (2008) |
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