Boechera paddoensis |
Boechera glaucovalvula |
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Mount Adams rock-cress, Mt. Adams rock-cress |
bluepod rockcress |
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Habit | Perennials; long-lived; (cespitose); apomictic; caudex usually woody. | Perennials; short- to long-lived; sexual; caudex usually not woody. |
Stems | 1–3 per caudex branch, arising from center of rosette near ground surface, or arising laterally proximal to sterile shoots, 1–2.5 dm, glabrous throughout. |
usually 1 per caudex branch, arising from center of rosette near ground surface, (0.6–)1–4.5 dm, densely pubescent proximally, trichomes short-stalked, 4–8-rayed, 0.1–0.4 mm, similarly pubescent distally. |
Basal leaves | blade narrowly oblanceolate, 1–3(–6) mm wide, margins usually entire, rarely apically few-toothed, not ciliate, surfaces sparsely pubescent, trichomes short-stalked, 4–8-rayed, 0.08–0.2 mm. |
blade linear to linear-oblanceolate, 2–4(–6) mm wide, margins entire, usually ciliate at petiole base, trichomes (simple or spurred), to 1.5 mm, surfaces densely pubescent, trichomes short-stalked, 4–8-rayed, 0.1–0.4 mm. |
Cauline leaves | 4–8, not concealing stem; blade auricles 1–2 mm, surfaces of distalmost leaves glabrous. |
6–10, not concealing stem; blade auricles absent, surfaces of distalmost leaves densely pubescent. |
Racemes | 5–12(–18)-flowered, usually unbranched. |
(5–)10–25-flowered, usually unbranched. |
Flowers | ascending at anthesis; sepals glabrous; petals lavender to purple, 4–5.5 × 1–1.5 mm, glabrous; pollen spheroid. |
divaricate at anthesis; sepals pubescent; petals light purple to lavender, 6–9 × 1.5–2.5 mm, glabrous; pollen ellipsoid. |
Fruiting pedicels | usually divaricate-ascending, rarely horizontal, straight, 2–5(–10) mm, glabrous. |
reflexed, strongly curved at base, 2–10 mm, pubescent, trichomes appressed, branched. |
Fruits | usually divaricate-ascending, rarely horizontal, not appressed to rachis, secund (often weakly so), straight, edges parallel, 3–5.5 cm × 1.5–2 mm; valves glabrous; ovules 42–54 per ovary; style 0.05–0.1 mm. |
strongly reflexed, sometimes appressed to rachis, often secund, straight, edges parallel, (1.8–)2.5–4.5 cm × 5–8 mm; valves glabrous; ovules 24–62 per ovary; style 0.2–0.6 mm. |
Seeds | uniseriate, 1.1–1.5 × 0.9–1.3 mm; wing continuous, 0.1–0.3 mm wide. |
biseriate, 5–6 × 4–5 mm; wing continuous, 1.8–2.5 mm wide. |
2n | = 14. |
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Boechera paddoensis |
Boechera glaucovalvula |
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Phenology | Flowering Jul–Aug. | Flowering Mar–Apr. |
Habitat | Rocky ridges | Rocky slopes and gravelly soil, usually under shelter of desert shrubs |
Elevation | 1500-2100 m (4900-6900 ft) | 600-1600 m (2000-5200 ft) |
Distribution |
OR; WA
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CA; NV
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Discussion | Morphological evidence suggests that Boechera paddoensis is an apomictic species that arose through hybridization between B. lemmonii and B. lyallii (see M. D. Windham and I. A. Al-Shehbaz 2007 for detailed comparison). Boechera paddoensis is known only from the mountains of central Washington and northeastern Oregon. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Boechera glaucovalvula, a distinctive sexual diploid that has the widest fruits in the genus, is known from Inyo, Mono, Riverside, and San Bernardino counties, California, and Clark and Nye counties, Nevada. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 392. | FNA vol. 7, p. 380. |
Parent taxa | Brassicaceae > tribe Boechereae > Boechera | Brassicaceae > tribe Boechereae > Boechera |
Sibling taxa | ||
Synonyms | Arabis lemmonii var. paddoensis | Arabis glaucovalvula |
Name authority | (Rollins) Windham & Al-Shehbaz: Harvard Pap. Bot. 11: 268. (2007) | (M. E. Jones) Al-Shehbaz: Novon 13: 385. (2003) |
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