Draba carnosula |
Draba pedicellata |
|
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Mount Eddy Draba, Mt. Eddy Draba |
Cusick's Draba, rocky-slope Draba, rocky-slope whitlow-grass, stalk whitlow-cress |
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Habit | Perennials; (loosely cespitose); caudex branched (somewhat surculose, with persistent leaf bases, branches sometimes terminating in sterile rosettes); scapose. | Perennials; (loosely cespitose); caudex branched (with persistent leaf bases, branches sometimes terminating in sterile rosettes); scapose. |
Stems | unbranched, 0.3–1.2 dm, glabrous throughout. |
unbranched, (0.15–)0.3–1.3(–1.6) dm, pubescent proximally, glabrous or nearly so distally, trichomes 2- or 3-rayed and simple, 0.1–1 mm. |
Basal leaves | rosulate; petiolate; petiole (persistent, midvein prominent), ciliate, (trichomes sparse, short-stalked, 2–4-rayed, sometimes with simple ones, 0.2–0.5 mm); blade (somewhat fleshy), oblanceolate or spatulate to obovate, 0.3–1.5 cm × 1.5–5 mm, margins entire, (pubescent as petiole), surfaces glabrous. |
rosulate; subsessile; blade oblanceolate to obovate, 0.4–1.6(–2) cm × 2–4(–6) mm, margins entire, (not ciliate), surfaces pubescent with stalked, 2–4-rayed trichomes, 0.2–0.9 mm, rarely adaxially with simple trichomes, (midvein obscure abaxially). |
Cauline leaves | 0. |
0. |
Racemes | 2–6-flowered, ebracteate, elongated in fruit; rachis not flexuous, glabrous. |
3–20(–27)-flowered, ebracteate, slightly to considerably elongated in fruit; rachis straight or flexuous, usually glabrous, rarely pubescent, trichomes simple and 2–4-rayed. |
Flowers | sepals ovate, 3–4 mm, glabrous; petals yellow, oblanceolate, 5–7 × 1.3–2 mm; anthers oblong, 0.7–0.9 mm. |
sepals broadly ovate, 1.8–2.5 mm, glabrous or pubescent, (trichomes simple and branched); petals yellow, spatulate, 3.5–5.5 × 1.5–2.2 mm; anthers ovate, 0.4–0.5 mm. |
Fruiting pedicels | divaricate-ascending, straight, 3–8 mm, usually glabrous, rarely trichomes simple. |
divaricate to horizontal, straight or curved upward (expanded basally or not), 4–9(–13) mm, glabrous or pubescent, trichomes simple and 2–4-rayed. |
Fruits | lanceolate to elliptic-lanceolate, plane, strongly flattened, 10–23 × 4–6 mm; valves (each with distinct midvein), glabrous; ovules 8–12 per ovary; style 2–3 mm. |
lanceolate to ellipsoid or ovoid, plane (not curved), inflated or slightly flattened, (4.2–)5.3–10(–13) × 2.5–4.5(–5.5) mm; valves glabrous or pubescent, trichomes simple and short-stalked, 2-rayed, 0.05–0.3 mm; ovules 8–16 per ovary; style 0.3–1(–1.2) mm. |
Seeds | (broadly winged), orbicular, 3–4.5 in diam.; (wing 1–1.5 mm wide). |
oblong, 1.2–1.6 × 0.7–0.9 mm. |
2n | = 20. |
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Draba carnosula |
Draba pedicellata |
|
Phenology | Flowering Jun–Jul. | Flowering May–Jul. |
Habitat | Open rocky hillsides | Rock outcrops, talus, steep gravel slopes in pinyon-juniper, mixed conifer, and subalpine meadow communities |
Elevation | 2800-3100 m (9200-10200 ft) | 2300-3800 m (7500-12500 ft) |
Distribution |
CA |
NV; UT
|
Discussion | Of conservation concern. Although Draba carnosula was reduced by Hitchcock to a variety of D. howellii, it differs significantly by having leafless flowering stems, 2–6-flowered racemes, and broadly winged seeds 3–4.5 mm in diam. Draba howellii almost always has 1–3-leaved stems, (5–)7–18(–25)-flowered racemes, and not winged, distally appendaged seeds 1–1.6 mm in diam. Draba carnosula is known only from a few collections from Mount Eddy in Trinity County and the north side of Mount Shasta in Siskiyou County. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Draba pedicellata is known from Elko, Eureka, Nye, and White Pine counties in northeastern Nevada and to Tooele County in northwestern Utah. It was considered a variety of D. cusickii by R. C. Rollins (1993); chromosome number, morphology, and geographic distribution suggest a closer relationship to D. sphaeroides. For a detailed discussion and comparison of these species, consult M. D. Windham (2004). N. H. Holmgren (2005b) divided D. pedicellata into two varieties: var. pedicellata, which is found on limestone throughout the species range, and var. wheelerensis, which is found on non-calcareous substrates in White Pine County. Although var. wheelerensis has slightly more spreading pedicels on somewhat more flexuous rachises, it appears to be little more than a dwarf alpine form of the species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 299. | FNA vol. 7, p. 328. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | D. howellii var. carnosula | D. cusickii var. pedicellata, D. pedicellata var. wheelerensis |
Name authority | O. E. Schulz: in H. G. A. Engler, Pflanzenr. 89[IV,105]: 82. (1927) | (Rollins & R. A. Price) Windham: Madroño 50: 221. (2004) |
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