Boechera repanda |
Boechera missouriensis |
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Greene's rockcress, Yosemite rockcress |
green rockcress |
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Habit | Perennials; short- to long-lived; sexual; caudex usually not woody. | Biennials; short-lived; sexual; caudex not evident. |
Stems | usually 1 per caudex branch, arising from center of rosette near ground surface, (1–)2–9 dm, densely pubescent proximally, trichomes short- to long-stalked, 2–6-rayed, 0.2–0.5 mm, rarely mixed with simple ones, to 1.5 mm, glabrous or sparsely pubescent distally. |
usually 1 per plant, arising from center of rosette near ground surface, 2–7.5 dm, sparsely pubescent proximally, trichomes simple, to 0.5 mm, or glabrous throughout. |
Basal leaves | blade broadly oblanceolate to obovate, 7–25(–50) mm wide, margins usually repand to coarsely dentate, rarely entire, not ciliate, surfaces moderately to densely pubescent, trichomes short- to long-stalked, 3–6-rayed, 0.2–0.5 mm. |
blade oblanceolate, 5–18 mm wide, margins lyrate-pinnatifid, often ciliate-mucronate on lobes, trichomes minute, surfaces glabrous or sparsely pubescent, trichomes simple, 0.1–0.5 mm. |
Cauline leaves | (3–)8–30, not concealing stem; blade auricles absent, surfaces of distalmost leaves sparsely pubescent. |
10–45, often concealing stem proximally; blade auricles 1–5 mm, surfaces glabrous. |
Racemes | 7–25-flowered, sometimes branched. |
18–47-flowered, sometimes branched. |
Flowers | erect to ascending at anthesis; sepals glabrous or sparsely pubescent; petals white, 3.5–6 × 0.8–1 mm, glabrous; pollen ellipsoid. |
ascending at anthesis; sepals glabrous; petals white, 5–10 × 1–1.5 mm, glabrous; pollen ellipsoid. |
Fruiting pedicels | erect to divaricate-ascending, straight, 3–10 mm, glabrous or pubescent, trichomes spreading, usually 2–5-rayed, rarely simple. |
suberect to divaricate-ascending, straight or slightly curved, 5–13 mm, glabrous. |
Fruits | divaricate-ascending, not appressed to rachis, not secund, usually curved, rarely straight, edges parallel, (3.5–)5–13.5 cm × 2.5–4 mm; valves glabrous or pubescent throughout; ovules 34–50 per ovary; style 0.5–1.5 mm. |
ascending to divaricate-ascending, not appressed to rachis, not secund, curved, edges parallel, 6–11 cm × 1.5–2 mm; valves glabrous; ovules 60–86 per ovary; style 0.1–1 mm. |
Seeds | uniseriate, 2.5–5(–6) × 2–3(–3.5) mm; wing continuous, 0.7–1.8 mm wide. |
uniseriate, 1.2–2 × 1–1.2 mm; wing continuous, 0.1–0.4 mm wide. |
2n | = 14. |
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Boechera repanda |
Boechera missouriensis |
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Phenology | Flowering Jun–Jul. | Flowering Mar–Jun. |
Habitat | Rock outcrops, talus, and gravelly soil in meadows and open pine forests | Rocky bluffs, wooded slopes, valley bottoms |
Elevation | 1600-3500 m (5200-11500 ft) | 50-300 m (200-1000 ft) |
Distribution |
CA; NV
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AR; CT; GA; IL; KY; MA; MI; MN; MO; NC; NY; OK; SC; WI
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Discussion | Boechera repanda is a sexual diploid that is distinguished from all other western North American species by its wide (10–50 mm), repand to coarsely dentate basal leaves. The form recognized as var. greenei appears to be a growth response to ecologically marginal habitats. Boechera repanda occurs sporadically in the Sierra Nevada and Transverse Ranges of California, and barely extends into the Carson Range in western Nevada. Arabis inamoena Greene (1911), not Greene (1908) is an illegitimate name, sometimes found in synonymy with Boechera repanda. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Boechera missouriensis occasionally has been treated as a variety of B. laevigata. With its significantly longer petals (5–10 versus 3–5 mm) and distinctive, lyrate-pinnatifid basal leaves that persist well beyond anthesis, it warrants recognition as a species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 402. | FNA vol. 7, p. 390. |
Parent taxa | Brassicaceae > tribe Boechereae > Boechera | Brassicaceae > tribe Boechereae > Boechera |
Sibling taxa | ||
Synonyms | Arabis repanda, Arabis repanda var. greenei | Arabis missouriensis, Arabis laevigata var. heterophylla, Arabis laevigata var. missouriensis, Arabis missouriensis var. deamii, Arabis viridis, Arabis viridis var. deamii |
Name authority | (S. Watson) Al-Shehbaz: Novon 13: 388. (2003) | (Greene) Al-Shehbaz: Novon 13: 387. (2003) |
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