Draba breweri |
Draba longisquamosa |
|
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Brewer's whitlow grass, cushion Draba |
granite Draba |
|
Habit | Perennials; (cespitose, grayish pubescent); caudex branched (sometimes covered with persistent leaf bases, branches short, compact); sometimes scapose. | Perennials; (cespitose); caudex branched (covered with persistent petiole remains, branches sometimes terminating in sterile rosettes); scapose. |
Stems | unbranched, (0.1–)0.2–1(–1.5) dm, pubescent throughout, trichomes stalked, 4–10-rayed, 0.1–0.3 mm. |
unbranched, 0.2–0.9 dm, hirsute throughout, trichomes simple, 0.2–0.8 mm. |
Basal leaves | rosulate; petiolate; petiole base ciliate, margin not ciliate, (trichomes simple and 2-rayed, 0.3–0.8 mm); blade oblanceolate to obovate, (0.3–)0.4–1.5(–2.5) cm × 1.5–3(–5) mm, margins usually entire, rarely dentate, surfaces densely pubescent with stalked, 4–10-rayed, stellate trichomes, 0.1–0.2 mm (sometimes 1 or more rays spurred). |
rosulate; shortly petiolate; petiole base and margin ciliate, (trichomes simple, 0.1–1 mm); blade oblanceolate to obovate, 0.5–2 cm × 2–5 mm, margins entire, surfaces pubescent with simple trichomes, 0.15–0.8 mm. |
Cauline leaves | 0–3(–6); sessile; blade oblong or lanceolate to ovate, margins entire (sometimes ciliate at base), surfaces usually pubescent as basal. |
0. |
Racemes | (5–)7–18(–24)-flowered, ebracteate, slightly to considerably elongated in fruit; rachis not flexuous, pubescent with stalked, 4–10-rayed trichomes, (0.1–0.3 mm). |
4–16-flowered, ebracteate, (subumbellate), slightly elongated in fruit; rachis not flexuous, hirsute as stem. |
Flowers | sepals (persistent), ovate, 1.2–2 mm, pubescent, (trichomes short-stalked, 2–6-rayed); petals white, spatulate to oblanceolate, 2–3 × 0.7–1.1 mm; anthers ovate, 0.2–0.25 mm. |
sepals (persistent) ovate, 1.5–2.2 mm, pubescent, (trichomes simple); petals (persistent), yellow, spatulate, 3.5–5 × 1.5–2 mm; anthers oblong, 0.5–0.6 mm. |
Fruiting pedicels | ascending, (sometimes slightly appressed to rachis), straight, 1.5–3(–4) mm, pubescent as rachis. |
divaricate to ascending (not decurrent basally), straight, 3–7 mm, hirsute as stem. |
Fruits | lanceolate or oblong to linear, usually slightly to strongly twisted, rarely plane, flattened, 3.5–9(–11) × 1.5–2.5 mm; valves pubescent, trichomes short-stalked, 2–5-rayed, 0.05–0.25 mm; ovules 28–40 per ovary; style 0.1–0.3(–0.4) mm. |
ovate to suborbicular, plane, flattened, 3.5–7 × 2.5–5 mm; valves pubescent, trichomes simple, 0.1–0.3 mm; ovules 10–16 per ovary; style 0.4–1 mm. |
Seeds | ovoid, 0.5–0.7 × 0.3–0.5 mm. |
ovoid, 1–1.2 × 0.7–0.8 mm. |
2n | = 32. |
|
Draba breweri |
Draba longisquamosa |
|
Phenology | Flowering Jul–Aug. | Flowering Jul. |
Habitat | Rock outcrops, talus, exposed ridges, alpine areas | Gravelly areas |
Elevation | 3100-4100 m (10200-13500 ft) | 3000-3900 m (9800-12800 ft) |
Distribution |
CA
|
CA |
Discussion | The circumscription of Draba breweri was expanded by R. C. Rollins (1993) to include D. cana. Plants of D. cana differ from those of D. breweri by being non-cespitose (versus cespitose) and taller [(4–)10–30(–38) versus (1–)2–9(–15) cm], and by having basally bracteate (versus ebracteate) racemes, and stems, pedicels, and sepals pubescent with a mixture of simple and branched (versus exclusively branched) trichomes. Draba breweri is known to us from Alpine, Fresno, Inyo, Mono, Plumas, Tulare, and Tuolumne counties. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Draba longisquamosa was treated as a synonym of D. lemmonii by both C. L. Hitchcock (1941) and R. C. Rollins (1993). We feel that the two taxa show sufficient morphological divergence and merit recognition as separate species (see I. A. Al-Shehbaz and M. D. Windham 2007 for more detailed discussion). Draba longisquamosa is currently known only from the southern Sierra Nevada in Fresno, Inyo, and Tulare counties. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 297. | FNA vol. 7, p. 317. |
Parent taxa | Brassicaceae > tribe Arabideae > Draba | Brassicaceae > tribe Arabideae > Draba |
Sibling taxa | ||
Synonyms | D. breweri var. sublaxa | |
Name authority | S. Watson: Proc. Amer. Acad. Arts 23: 260. (1888) | O. E. Schulz: in H. G. A. Engler, Pflanzenr. 89[IV,105]: 94. (1927) |
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