Boechera dentata |
Boechera rollinsiorum |
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Short's rockcress |
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Habit | Biennials; short-lived; sexual; caudex present or absent. | Perennials; long-lived; sexual; caudex woody. |
Stems | 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. |
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 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. |
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 | 4–20, rarely concealing stem; blade auricles 1–8 mm, surfaces of distalmost leaves sparsely pubescent. |
5–9, not concealing stem; blade auricles 0.5–1 mm, surfaces of distalmost leaves sparsely to moderately pubescent. |
Racemes | 14–66-flowered, sparingly branched. |
5–11-flowered, usually unbranched. |
Flowers | divaricate at anthesis; sepals glabrous or sparsely pubescent; petals white or cream, 2–3.5 × 0.7–1 mm, glabrous; pollen ellipsoid. |
divaricate-ascending at anthesis; sepals pubescent; petals pale purple, 6–8 × 1.5–2 mm, glabrous; pollen ellipsoid. |
Fruiting pedicels | divaricate-ascending to slightly descending, straight, 1–6 mm, glabrous or pubescent, trichomes appressed, branched. |
descending, straight to slightly recurved, 4–6 mm, pubescent, trichomes appressed, branched. |
Fruits | 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. |
(immature) pendent, not appressed to rachis, not secund, straight, edges parallel; valves glabrous. |
Seeds | uniseriate, 0.7–1.1 × 0.5–0.6 mm; not winged. |
not seen. |
Boechera dentata |
Boechera rollinsiorum |
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Phenology | Flowering Apr–Jun. | Flowering Jun. |
Habitat | Bluffs and rocky ledges, wooded slopes, floodplains | Metamorphosed igneous gravel on steep slopes |
Elevation | 100-300 m (300-1000 ft) | ca. 2100 m (ca. 6900 ft) |
Distribution |
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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ID |
Discussion | Sisymbrium dentatum Torrey is an illegitimate name that pertains to Iodanthus dentatus. (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. 373. | FNA vol. 7, p. 403. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Shortia dentata, Arabis dentata var. phalacrocarpa, Arabis perstellata var. shortii, Arabis shortii, Arabis shortii var. phalacrocarpa, B. shortii, Iodanthus dentatus | |
Name authority | (Rafinesque) Al-Shehbaz & Zarucchi: Harvard Pap. Bot. 13: 293. (2008) | Windham & Al-Shehbaz: Harvard Pap. Bot. 11: 81. (2006) |
Web links |