Boechera quebecensis |
Boechera dentata |
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Short's rockcress |
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Habit | Biennials or perennials; short-lived; apomictic; caudex present or absent. | 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 sessile, 2–4-rayed, 0.15–0.5 mm, glabrous 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 oblanceolate, 5–15 mm wide, margins denticulate, ciliate proximally, trichomes (simple), to 1 mm, surfaces moderately pubescent, trichomes subsessile, (2- or) 3–7-rayed, 0.1–0.3 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 | 4–15, not concealing stem; blade auricles 1–3.5 mm, surfaces of distalmost leaves glabrous. |
4–20, rarely concealing stem; blade auricles 1–8 mm, surfaces of distalmost leaves sparsely pubescent. |
Racemes | 11–41-flowered, usually unbranched. |
14–66-flowered, sparingly branched. |
Flowers | divaricate at anthesis; sepals pubescent; petals white, 6–7 × 1–2 mm, glabrous; pollen spheroid. |
divaricate at anthesis; sepals glabrous or sparsely pubescent; petals white or cream, 2–3.5 × 0.7–1 mm, glabrous; pollen ellipsoid. |
Fruiting pedicels | horizontal to slightly descending, curved to straight, 3–8(–14) mm, glabrous or with some subappressed, branched trichomes. |
divaricate-ascending to slightly descending, straight, 1–6 mm, glabrous or pubescent, trichomes appressed, branched. |
Fruits | horizontal to slightly descending, not appressed to rachis, secund, straight, edges parallel, 3–6 cm × 1.5–2 mm; valves glabrous; ovules 56–94 per ovary. |
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, 1.2–1.5 × 1–1.3 mm; wing continuous, 0.1–0.15 mm wide. |
uniseriate, 0.7–1.1 × 0.5–0.6 mm; not winged. |
Boechera quebecensis |
Boechera dentata |
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Phenology | Flowering Jun–Jul. | Flowering Apr–Jun. |
Habitat | Calcareous rock outcrops and talus slopes | Bluffs and rocky ledges, wooded slopes, floodplains |
Elevation | 0-300 m (0-1000 ft) | 100-300 m (300-1000 ft) |
Distribution |
QC |
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 | Morphological evidence suggests that Boechera quebecensis is an apomictic species that arose through hybridization between B. holboellii and B. stricta; it is most likely to be confused with B. grahamii (see M. D. Windham and I. A. Al-Shehbaz 2007b for detailed comparison). (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. 401. | FNA vol. 7, p. 373. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Arabis divaricarpa var. dechamplainii | Shortia dentata, Arabis dentata var. phalacrocarpa, Arabis perstellata var. shortii, Arabis shortii, Arabis shortii var. phalacrocarpa, B. shortii, Iodanthus dentatus |
Name authority | Windham & Al-Shehbaz: Harvard Pap. Bot. 12: 246. (2007) | (Rafinesque) Al-Shehbaz & Zarucchi: Harvard Pap. Bot. 13: 293. (2008) |
Web links |