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coast mountain Draba, coast mountain whitlow-grass, coast mountain whitlow-grass Draba, Rainier Draba

kathul mountain Draba

Habit Perennials; (cespitose, forming tufts); caudex branched (with persistent leaf bases, branches some terminating in sterile rosettes); scapose. Perennials; (cespitose); caudex often branched (covered with persistent leaves or leaf remains, branches sometimes terminating in sterile rosettes); not scapose.
Stems

unbranched, 0.2–0.6(–0.8) dm, often pubescent throughout, sometimes glabrate distally, trichomes simple, 0.4–1 mm, and 2–4-rayed, 0.1–0.4 mm.

unbranched, (0.4–)0.9–2.7(–3.5) dm, pubescent proximally, glabrous distally, trichomes simple, 0.2–1 mm, and often smaller, fewer short-stalked, 2–4-rayed ones.

Basal leaves

rosulate;

subsessile;

petiole base and margin ciliate, (trichomes simple, 0.4–1.4 mm);

blade oblanceolate to obovate or suborbicular, 0.3–1 cm × 2–4.5 mm, margins entire, surfaces pubescent, abaxially with stalked, 2–10-rayed, stellate trichomes, 0.2–0.8 mm, adaxially with simple trichomes, 0.4–1 mm, sometimes with smaller, 2–4-rayed ones, (midvein obscure).

rosulate; petiolate;

petiole (0–0.7 cm), margin ciliate;

blade oblanceolate to obovate, (0.3–)0.6–2.1(–2.8) cm × (1.5–)2.5–5(–9) mm, margins entire or sparsely denticulate, (ciliate, trichomes simple, 0.2–1.1 mm), surfaces pubescent with stalked, cruciform, and 2- or 3-rayed trichomes, (rays sometimes spurred), 0.1–0.6 mm, sometimes mostly simple trichomes adaxially.

Cauline leaves

0.

1–6;

sessile;

blade ovate or oblong to lanceolate, margins usually entire, rarely sparsely denticulate, surfaces pubescent as basal.

Racemes

(2–)4–10(–14)-flowered, ebracteate, elongated in fruit;

rachis not flexuous, pubescent as stem or glabrous.

7–25-flowered, ebracteate, elongated in fruit;

rachis not flexuous, glabrous.

Flowers

sepals ovate, 2–3 mm, pubescent, (trichomes simple with fewer, 2-rayed ones);

petals bright yellow, obovate, 4–6 × 2–3.5 mm;

anthers oblong, 0.4–0.5 mm.

sepals ovate, 1.5–2.2 mm, pubescent, (trichomes simple and short-stalked, 2-rayed);

petals white, obovate, 4–6 × 1.5–2.5 mm;

anthers ovate, 0.4–0.5 mm.

Fruiting pedicels

ascending to divaricate-ascending, straight or slightly curved upward, 3–7(–9) mm, pubescent or glabrous, trichomes simple and 2–4-rayed.

divaricate-ascending, usually straight, rarely curved, (4–)7–18 mm, glabrous.

Fruits

elliptic to lanceolate or ovate to suborbicular, plane, flattened, 4–8(–10) × 3–4.5 mm;

valves puberulent, trichomes simple with fewer 2-rayed ones, 0.1–0.35 mm;

ovules 12–16 per ovary;

style 0.5–0.9(–1.1) mm.

linear-lanceolate to narrowly elliptic, plane, flattened, 5–13 × 1.5–2 mm;

valves glabrous;

ovules 20–30 per ovary;

style 0.6–1.5 mm.

Seeds

oblong, 1.5–2 × 1–1.3 mm.

oblong, 0.9–1.2 × ca. 0.5 mm.

2n

= 72.

= 48.

Draba ruaxes

Draba murrayi

Phenology Flowering Jun–Jul. Flowering Jun–Jul.
Habitat Rock outcrops, talus slopes, ridges, alpine summits Rock outcrops and talus, open forests, dry slopes, alluvial gravels
Elevation 500-2400 m (1600-7900 ft) 150-900 m (500-3000 ft)
Distribution
from FNA
AK; WA; AB; BC; YT
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; YT
[BONAP county map]
Discussion

C. L. Hitchcock (1941) treated Draba ruaxes as a variety of D. ventosa; as demonstrated by G. A. Mulligan (1971b), the two are quite distinct. Draba ruaxes is an outcrossing hexaploid with well-formed anthers and pollen, and abundant, simple trichomes on leaves, stems, sepals, and fruits. By contrast, D. ventosa is an apomictic triploid with abortive anthers and/or pollen, and no simple trichomes anywhere on the plant.

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

Of conservation concern.

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

Source FNA vol. 7, p. 334. FNA vol. 7, p. 321.
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. 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. 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. argyrea, 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. 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. ventosa var. ruaxes
Name authority Payson & H. St. John: Proc. Biol. Soc. Wash. 43: 117. (1930) G. A. Mulligan: Canad. J. Bot. 57: 1874. (1979)
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