Draba yukonensis |
Draba carnosula |
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Yukon whitlowgrass |
Mount Eddy Draba, Mt. Eddy Draba |
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Habit | Perennials; (short-lived); caudex simple or branched (with persistent leaf remains); not scapose. | Perennials; (loosely cespitose); caudex branched (somewhat surculose, with persistent leaf bases, branches sometimes terminating in sterile rosettes); scapose. |
Stems | branched, 0.4–2 dm, pubescent throughout, trichomes simple, 0.3–1.2 mm, and 2–6-rayed, 0.05–0.6 mm. |
unbranched, 0.3–1.2 dm, glabrous throughout. |
Basal leaves | rosulate; subsessile; blade oblanceolate to narrowly so, 0.3–1 cm × 0.5–2 mm, margins entire, (ciliate, trichomes simple, to 1.3 mm), surfaces pubescent, abaxially with (rigid), simple and 2-rayed trichomes, 0.4–1.2 mm, sometimes with short-stalked, 3–6-rayed ones, 0.1–0.3 mm, adaxially with simple trichomes. |
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. |
Cauline leaves | 1–3; sessile; blade ovate to oblong, margins entire, surfaces pubescent as basal. |
0. |
Racemes | 5–20-flowered, ebracteate, considerably elongated in fruit; rachis not flexuous, pubescent as stem. |
2–6-flowered, ebracteate, elongated in fruit; rachis not flexuous, glabrous. |
Flowers | sepals ovate, 1.2–1.6 mm, pubescent, (trichomes simple and 2–4-rayed); petals white, spatulate, 1.5–2 × 0.7–0.8 mm; anthers ovate, ca. 0.2 mm. |
sepals ovate, 3–4 mm, glabrous; petals yellow, oblanceolate, 5–7 × 1.3–2 mm; anthers oblong, 0.7–0.9 mm. |
Fruiting pedicels | erect to ascending, straight, 0.5–3 mm, pubescent as stem. |
divaricate-ascending, straight, 3–8 mm, usually glabrous, rarely trichomes simple. |
Fruits | ovoid to oblong, plane, not flattened, 2–5 × 1.5–2 mm; valves pubescent, trichomes short-stalked, 4- or 5-rayed, 0.05–0.3 mm; ovules 36–52 per ovary; style 0.1–0.3 mm. |
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. |
Seeds | oblong, 0.6–0.8 × 0.3–0.4 mm. |
(broadly winged), orbicular, 3–4.5 in diam.; (wing 1–1.5 mm wide). |
Draba yukonensis |
Draba carnosula |
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Phenology | Flowering late May–Jun. | Flowering Jun–Jul. |
Habitat | Open stony ridges on ancient beach in grassy areas and aspen stands | Open rocky hillsides |
Elevation | ca. 600 m (ca. 2000 ft) | 2800-3100 m (9200-10200 ft) |
Distribution |
YT |
CA |
Discussion | Of conservation concern. Draba yukonensis is known only from Kluane National Park, southwestern Yukon Territory. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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.) |
Source | FNA vol. 7, p. 346. | FNA vol. 7, p. 299. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | D. howellii var. carnosula | |
Name authority | A. E. Porsild: Publ. Bot. (Ottawa) 4: 37, plate 7. (1975) | O. E. Schulz: in H. G. A. Engler, Pflanzenr. 89[IV,105]: 82. (1927) |
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