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alpine whitlow-grass, golden alpine Draba, golden Draba, great alpine whitlow-grass, Mt. Lassen Draba, Mt. Lassen Draba whitlow-grass, Mt. Lassen whitlow-grass

silver Draba

Habit Perennials; (short-lived); caudex simple or branched (poorly developed, with persistent dry leaves); not scapose. Perennials; caudex branched (branches loose, creeping, sometimes terminating in sterile shoots); scapose.
Stems

unbranched or branched, 0.3–1.5 dm, hirsute throughout, trichomes simple and long-stalked, 2–4-rayed, 0.2–1.5 mm.

unbranched, (0.2–)0.3–0.8(–1.1) dm, pubescent proximally, glabrous distally, trichomes short-stalked to subsessile, 5–8-rayed, 0.05–0.2 mm.

Basal leaves

(forming dense clusters); rosulate;

sessile;

blade oblanceolate to linear, (0.7–)1–2.5(–3.2) cm × 2–3.5(–5) mm, margins entire, (ciliate, trichomes simple and 2-rayed, 0.5–1.5 mm), surfaces densely hirsute, abaxially with stalked, 3–5-rayed trichomes, 0.1–0.5 mm, adaxially with simple and long-stalked, 2-rayed trichomes, to 1 mm, with smaller, 3–5-rayed ones.

rosulate;

subsessile;

petiole base and margin not ciliate, (midvein obscure abaxially);

blade oblanceolate to obovate, 0.3–0.7(–1.2) cm × 1–2.5(–4) mm, margins entire, surfaces canescent with short-stalked, 8–12-rayed, stellate trichomes, 0.1–0.2 mm.

Cauline leaves

5–33;

sessile;

blade oblong to linear, margins entire, surfaces pubescent as basal.

0.

Racemes

12–83-flowered, ebracteate or proximalmost 1–9 flowers bracteate, slightly or not elongated in fruit;

rachis not flexuous, hirsute as stem.

2–8(–12)-flowered, ebracteate, elongated in fruit;

rachis slightly flexuous, usually glabrous, rarely sparsely pubescent as stem.

Flowers

sepals ovate, 2.5–4 mm, glabrous;

petals bright yellow, linear to linear-oblanceolate, 4–6 × 0.5–1(–1.2) mm;

anthers narrowly oblong, 0.8–1 mm.

sepals ovate, 2–3 mm, pubescent, (trichomes 4–6-rayed);

petals yellow, oblanceolate, 4–6 × 1.5–3 mm;

anthers ovate, 0.5–0.6 mm.

Fruiting pedicels

horizontal to divaricate, usually straight, rarely curved upward, (3–)5–12(–19) mm, hirsute as stem.

divaricate-ascending, straight or slightly curved upward, (4–)5–12(–19) mm, glabrous.

Fruits

oblong or, rarely, oblong-ovate, plane, flattened, (6–)9–14(–16) × 3–5 mm;

valves pubescent, trichomes stalked, 2–4-rayed, 0.07–0.5 mm;

ovules 10–20 per ovary;

style (0.6–)1–1.6(–2) mm.

lanceolate to elliptic or ovate, plane or slightly twisted, flattened, 5–11 × 2–3.5(–4.5) mm, (symmetric);

valves often puberulent, sometimes glabrous, trichomes simple and subsessile, 2–4-rayed, 0.03–0.2 mm;

ovules 8–14 per ovary;

style (0.7–)1–1.8(–2.4) mm.

Seeds

oblong, 1.4–1.9 × 0.8–1.1 mm.

oblong, 1.2–1.8 × 0.8–1.1 mm.

2n

= 20.

= 36.

Draba aureola

Draba argyrea

Phenology Flowering Jul–Aug. Flowering Apr–Jul.
Habitat Open conifer forests, alpine meadows and moraines, talus slopes Rock crevices, ledges, talus slopes
Elevation 2200-3200 m (7200-10500 ft) 1000-3100 m (3300-10200 ft)
Distribution
from FNA
CA; OR; WA
[WildflowerSearch map]
[BONAP county map]
from FNA
ID
[BONAP county map]
Discussion

Draba aureola is known from Lassen, Shasta, and Siskiyou counties in California, Deschutes County in Oregon, and Lewis and Pierce counties in Washington.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

M. A. Beilstein and M. D. Windham (2003) hypothesized that Draba argyrea is an allopolyploid derived through hybridization between D. lonchocarpa and D. sphaerocarpa. The species is restricted to Blaine, Boise, Custer, and Elmore counties in central Idaho.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 7, p. 295. FNA vol. 7, p. 292.
Parent taxa Brassicaceae > tribe Arabideae > Draba Brassicaceae > tribe Arabideae > Draba
Sibling taxa
D. abajoensis, D. albertina, D. aleutica, D. alpina, D. aprica, D. arabisans, D. arctica, D. arctogena, D. argyrea, D. arida, D. asprella, D. asterophora, D. aurea, D. bifurcata, D. borealis, D. brachycarpa, D. brachystylis, D. breweri, D. burkei, D. californica, D. cana, D. carnosula, D. chamissonis, D. cinerea, D. corrugata, D. corymbosa, D. crassa, D. crassifolia, D. cruciata, D. cuneifolia, D. cusickii, D. cyclomorpha, D. daviesiae, D. densifolia, D. exunguiculata, D. fladnizensis, D. glabella, D. globosa, D. graminea, D. grandis, D. grayana, D. heilii, D. helleriana, D. hitchcockii, D. howellii, D. incana, D. incerta, D. incrassata, D. inexpectata, D. jaegeri, D. juvenilis, D. kassii, D. kluanei, D. lactea, D. lemmonii, D. lonchocarpa, D. longisquamosa, D. macounii, D. maguirei, D. malpighiacea, D. micropetala, D. mogollonica, D. monoensis, D. mulliganii, D. murrayi, D. nemorosa, D. nivalis, D. norvegica, D. novolympica, D. oblongata, D. ogilviensis, D. oligosperma, D. oreibata, D. oxycarpa, D. palanderiana, D. pauciflora, D. paucifructa, D. paysonii, D. pectinipila, D. pedicellata, D. pennellii, D. petrophila, D. pilosa, D. platycarpa, D. porsildii, D. praealta, D. pterosperma, D. ramosissima, D. ramulosa, D. rectifructa, D. reptans, D. ruaxes, D. santaquinensis, D. saxosa, D. scotteri, D. serpentina, D. sharsmithii, D. sibirica, D. sierrae, D. simmonsii, D. smithii, D. sobolifera, D. spectabilis, D. sphaerocarpa, D. sphaeroides, D. standleyi, D. stenoloba, D. stenopetala, D. streptobrachia, D. streptocarpa, D. subalpina, D. subcapitata, D. subumbellata, D. trichocarpa, D. ventosa, D. verna, D. viridis, D. weberi, D. yukonensis, D. zionensis
D. abajoensis, D. albertina, D. aleutica, D. alpina, D. aprica, D. arabisans, D. arctica, D. arctogena, D. arida, D. asprella, D. asterophora, D. aurea, D. aureola, D. bifurcata, D. borealis, D. brachycarpa, D. brachystylis, D. breweri, D. burkei, D. californica, D. cana, D. carnosula, D. chamissonis, D. cinerea, D. corrugata, D. corymbosa, D. crassa, D. crassifolia, D. cruciata, D. cuneifolia, D. cusickii, D. cyclomorpha, D. daviesiae, D. densifolia, D. exunguiculata, D. fladnizensis, D. glabella, D. globosa, D. graminea, D. grandis, D. grayana, D. heilii, D. helleriana, D. hitchcockii, D. howellii, D. incana, D. incerta, D. incrassata, D. inexpectata, D. jaegeri, D. juvenilis, D. kassii, D. kluanei, D. lactea, D. lemmonii, D. lonchocarpa, D. longisquamosa, D. macounii, D. maguirei, D. malpighiacea, D. micropetala, D. mogollonica, D. monoensis, D. mulliganii, D. murrayi, D. nemorosa, D. nivalis, D. norvegica, D. novolympica, D. oblongata, D. ogilviensis, D. oligosperma, D. oreibata, D. oxycarpa, D. palanderiana, D. pauciflora, D. paucifructa, D. paysonii, D. pectinipila, D. pedicellata, D. pennellii, D. petrophila, D. pilosa, D. platycarpa, D. porsildii, D. praealta, D. pterosperma, D. ramosissima, D. ramulosa, D. rectifructa, D. reptans, D. ruaxes, D. santaquinensis, D. saxosa, D. scotteri, D. serpentina, D. sharsmithii, D. sibirica, D. sierrae, D. simmonsii, D. smithii, D. sobolifera, D. spectabilis, D. sphaerocarpa, D. sphaeroides, D. standleyi, D. stenoloba, D. stenopetala, D. streptobrachia, D. streptocarpa, D. subalpina, D. subcapitata, D. subumbellata, D. trichocarpa, D. ventosa, D. verna, D. viridis, D. weberi, D. yukonensis, D. zionensis
Synonyms D. aureola var. paniculata D. argyrea var. glabrescens
Name authority S. Watson: in W. H. Brewer et al., Bot. California 2: 430. (1880) Rydberg: Bull. Torrey Bot. Club 30: 251. (1903)
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