Draba globosa |
Draba nemorosa |
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beavertip Draba, rockcress Draba, round-fruit Draba |
woodland Draba, woodland whitlow-grass, woods Draba, woods whitlow-grass, yellow whitlow-grass |
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Habit | Perennials; (cespitose, pulvinate); caudex branched (with persistent leaves, branches sometimes terminating in sterile rosettes); scapose. | Annuals; not scapose. |
Stems | unbranched, 0.1–0.5 dm, glabrous. |
unbranched or branched proximally, (0.3–)0.6–4.5(–6) dm, densely pubescent proximally, glabrous distally, trichomes simple, 0.5–1.3 mm, and stalked, 2–4-rayed, 0.1–0.5 mm. |
Basal leaves | rosulate; sessile; blade (not fleshy), narrowly oblanceolate or lanceolate to linear, (0.2–)0.3–0.8 cm × 0.5–1.6(–2) mm, margins entire (ciliate, trichomes simple, 0.1–0.8 mm, apex acute, trichomes usually longer), surfaces glabrous, (midvein obscure abaxially). |
rosulate or not, petiolate; petiole ciliate throughout; blade oblong-obovate or oblanceolate, (0.4–)1–3.5(–5) cm × (2–)5–15(–20) mm, margins usually dentate to denticulate, rarely subentire, surfaces sparsely to densely pubescent with stalked, 2- or 3-rayed, and cruciform trichomes, 0.1–0.5 mm. |
Cauline leaves | 0. |
4–12(–15); sessile; blade broadly ovate to oblong, margins dentate or denticulate, surfaces pubescent, abaxially as basal, adaxially with primarily simple, and 2- or 3-rayed trichomes. |
Racemes | 2–5(–7)-flowered, ebracteate, slightly elongated in fruit; rachis not flexuous, glabrous. |
(10–)18–60(–92)-flowered, ebracteate, considerably elongated in fruit; rachis not flexuous (straight), glabrous. |
Flowers | sepals (persistent to near fruit maturity), ovate to broadly oblong, 2–3 mm, glabrous; petals white to pale yellow, obovate, 2.5–4 × 1.2–2 mm; anthers oblong, 0.4–0.6 mm. |
sepals ovate, (0.7–)0.9–1.6 mm, sparsely pubescent, (trichomes simple); petals yellow, spatulate to oblanceolate, (1.2–)1.7–2.2(–2.5) × (0.4–)0.6–1 mm, (deeply notched); anthers broadly ovate to subreniform, 0.1–0.2 mm. |
Fruiting pedicels | divaricate-ascending, straight or slightly curved, 2–6 mm, glabrous. |
divaricate, straight, 7–28(–35) mm [(1.5–)2–7 times longer than fruit], glabrous. |
Fruits | ovate, plane, flattened, 4.5–8 × 2.5–4 mm; valves (distinctly veined), glabrous; ovules 8–16 per ovary; style (0.1–)0.2–0.6 mm. |
oblong to elliptic or, rarely, oblong-oblanceolate, plane, slightly flattened, (3–)5–8 (–10) × 1.5–2.5 mm; valves glabrous or puberulent, trichomes simple, antrorse, 0.05–0.2 mm; ovules (30–)36–60(–72) per ovary; style 0.01–0.1 mm. |
Seeds | oblong, 1.1–1.4 × 0.8–1 mm. |
ovoid, 0.5–0.7(–0.8) × 0.3–0.4(–0.5) mm. |
2n | = 16. |
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Draba globosa |
Draba nemorosa |
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Phenology | Flowering Jun–Aug. | Flowering Apr–Jul. |
Habitat | Ridges, talus, alpine tundra and meadows | Rock outcrops, open wooded slopes, meadows and prairies, stream banks, roadsides, disturbed gravelly grounds, waste places |
Elevation | 2700-3900 m (8900-12800 ft) | 0-2700 m (0-8900 ft) |
Distribution |
ID; MT; UT; WY
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AK; CA; CO; IA; ID; MI; MN; MT; ND; NE; NV; OR; SD; UT; WA; WI; WY; AB; BC; MB; NT; NU; ON; QC; SK; YT; Europe; Asia [Introduced in North America; introduced also in Australia]
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Discussion | Draba globosa is an apomictic species closely related to D. burkei (M. D. Windham, unpubl.). Though often treated as a variety of D. densifolia, it is morphologically and phyletically distinct from that species. Both R. C. Rollins (1993) and N. H. Holmgren (2005b) indicated that the species occurs in Colorado, but we have not seen material for that state. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 7, p. 308. | FNA vol. 7, p. 321. |
Parent taxa | Brassicaceae > tribe Arabideae > Draba | Brassicaceae > tribe Arabideae > Draba |
Sibling taxa | ||
Synonyms | D. apiculata, D. densifolia var. apiculata, D. densifolia var. decipiens, D. densifolia var. globosa | D. dictyota, D. nemoralis, D. nemorosa var. brevisilicula, D. nemorosa var. hebecarpa, D. nemorosa var. leiocarpa, Tomostima nemorosa |
Name authority | Payson: Amer. J. Bot. 4: 257. (1917) | Linnaeus: Sp. Pl. 2: 643. (1753) |
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