Draba ogilviensis |
Draba albertina |
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Ogilvie Range Draba |
Alaska Draba, Alaska whitlow-grass, Alberta whitlow grass, slender Draba, slender whitlow-grass |
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Habit | Perennials; (stoloniferous); caudex branched (sparsely covered with petiole remains, branches slender, creeping, loosely matted); often scapose. | Annuals, biennials, or perennials; caudex (or base) simple or branched (poorly developed); rarely scapose. |
Stems | unbranched, 0.4–1.5 dm, glabrous or pubescent throughout, trichomes simple and short-stalked, 2- or 3-rayed, 0.1–0.5 mm. |
branched distally, (0.3–)0.5–3(–4.2) dm, pubescent proximally, often glabrous distally, trichomes simple, 0.1–1 mm, sometimes with fewer, stalked, 2-rayed ones. |
Basal leaves | not rosulate; (subopposite); petiolate; petiole base and margin ciliate or not, (trichomes simple, 0.2–0.8 mm); blade oblanceolate or lanceolate, 0.5–1.5 cm × 1.5–5 mm, margins entire, surfaces glabrous or sparsely pubescent with simple and stalked, 2–4-rayed trichomes, 0.1–0.5 mm, (midvein obscure abaxially). |
rosulate; shortly petiolate; petiole (0–0.5 cm), ciliate throughout; blade obovate to oblanceolate or linear-lanceolate, (0.3–)1–2.8(–3.5) cm × (1–)2–6(–9) mm, margins entire or denticulate, (ciliate, trichomes simple, 0.4–1 mm), surfaces usually pubescent, abaxially with stalked, 2–4-rayed trichomes, 0.05–0.4(–0.5) mm, (rarely with simple trichomes along midvein), adaxially with simple trichomes sometimes also with 2-rayed ones, 0.07–0.4 mm, rarely glabrous. |
Cauline leaves | (0 or) 1 or 2; (subopposite); sessile; blade ovate or oblong, margins entire, surfaces pubescent as basal. |
(0 or) 1–3(–5); sessile; blade lanceolate to elliptic or ovate, margins entire or denticulate, surfaces pubescent as basal. |
Racemes | 5–13-flowered, ebracteate, elongated in fruit; rachis not or slightly flexuous, glabrous or pubescent as stem. |
(2–)6–30(–50)-flowered, ebracteate, elongated in fruit; rachis straight or, rarely, flexuous, glabrous. |
Flowers | sepals ovate, 2–3 mm, glabrous or pubescent, (trichomes simple); petals golden yellow, obovate, 3.5–6 × 2–3 mm; anthers ovate, 0.3–0.5 mm. |
(chasmogamous, petaliferous); sepals ovate, 1.4–2.1 mm, glabrous or sparsely pubescent, (trichomes simple); petals yellow, spatulate to oblanceolate, 2–3.2 × 0.7–1.2 mm; anthers ovate, 0.15–0.25 mm. |
Fruiting pedicels | horizontal to divaricate, often curved upward, 6–13(–17) mm, glabrous or sparsely pubescent, trichomes simple and 2-rayed. |
divaricate-ascending or horizontal, (not appressed to rachis), usually straight, rarely curved upward, (3–)5–14(–16) mm (subequaling or shorter than fruit), usually glabrous, rarely sparsely puberulent. |
Fruits | oblong, plane, flattened, 6–9 × 2–3 mm; valves glabrous; ovules 8–20 per ovary; style 0.4–1 mm. |
lanceolate to narrowly elliptic or linear, plane, flattened, (4–)6–12(–15) × (1–)1.4–2.1 mm; valves glabrous; ovules (20–)24–38(–44) per ovary; style 0.01–0.12 mm. |
Seeds | ovoid, 0.9–1 × ca. 0.6 mm. |
oblong, 0.7–1 × 0.4–0.5 mm. |
2n | = 16. |
= 24. |
Draba ogilviensis |
Draba albertina |
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Phenology | Flowering Jun–Aug. | Flowering Jun–Aug. |
Habitat | Tundra, river flats and banks, exposed talus slopes, hummocks in wet sedge meadows | Open woodlands, pine forests, meadows, rocky knolls, alpine slopes, stream banks, disturbed areas |
Elevation | 900-2200 m (3000-7200 ft) | 900-3700 m (3000-12100 ft) |
Distribution |
AK; NT; YT |
AK; AZ; CA; CO; ID; MT; NM; NV; OR; UT; WA; WY; AB; BC; NT; YT
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Discussion | The limits of Draba ogilviensis were confused by authors who reduced it to synonymy of D. juvenilis or D. sibirica. A thorough discussion of the three species and their distinguishing characteristics was provided by D. F. Murray and C. L. Parker (1999). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
O. E. Schulz (1927) and C. L. Hitchcock (1941) confused the limits of Draba albertina, D. crassifolia, and D. stenoloba; the latter author treated the first two species as conspecific. G. A. Mulligan (1975) demonstrated that the three taxa are chromosomally and morphologically distinct (see D. crassifolia and D. stenoloba for differences from D. albertina). The ranges of D. albertina and D. crassifolia overlap extensively, and occasional sterile hybrids are encountered. The Alaskan record of Draba albertina is based on Minard 4 (ALA), collected on the northern coast of Afognak Island (58°22’N, 152°28’W). The record from New Mexico is based on O’Kane & Hedin 3871 (ISTC, SJC), collected in Chuska Mountains (36°8’11”N, 108°54’19”W). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 324. | FNA vol. 7, p. 288. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | D. crassifolia var. albertina, D. crassifolia var. nevadensis, D. deflexa, D. nitida, D. nitida var. nana, D. stenoloba var. nana, D. stenoloba var. ramosa | |
Name authority | Hultén: Bot. Not. 119: 315, fig. 2. (1966) | Greene: Pittonia 4: 312. (1901) |
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