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Mt. Olympic Draba, Olympic Draba, Olympic Mountains Draba, Payson's Draba, Payson's whitlow-grass, Trelease's Draba, Trelease's whitlow-grass

branch Draba

Habit Perennials; (cespitose, densely pulvinate); caudex branched (covered with persistent leaves, branches creeping, sometimes terminating in sterile rosettes); scapose. Perennials; caudex branched (well-developed, with persistent leaf bases); not scapose.
Stems

unbranched, 0.05–0.4 dm, densely pubescent throughout, trichomes simple, 0.4–0.8 mm, and stalked, 2–5-rayed, 0.1–0.5 mm.

unbranched proximally, paniculately branched distally, 0.7–3.8(–5) dm, pubescent proximally, trichomes short-stalked, 2–4-rayed, 0.1–0.6 mm, sometimes with simple ones, 0.4–0.8 mm.

Basal leaves

(densely imbricate); rosulate;

sessile;

blade oblong to linear-oblanceolate, 0.2–0.8 cm × 0.5–1.5 mm, margins entire, (ciliate, trichomes simple and spurred, 0.3–1.2 mm), surfaces densely pubescent, abaxially with stalked, 2–12-rayed stellate trichomes, 0.1–0.6 mm, adaxially with simple and 2-rayed ones, 0.3–0.8 mm.

rosulate; petiolate;

petiole (to 2 cm), ciliate (trichomes simple, 0.3–0.5 mm);

blade oblanceolate, (0.7–)1–5.5 cm × 2–8 mm, margins dentate, surfaces pubescent with short-stalked to subsessile, 3- or 4-rayed trichomes, 0.1–0.5 mm, adaxially sometimes also simple, 0.4–1.3 mm.

Cauline leaves

0.

(5–)7–15(–21);

sessile;

blade ovate to oblong or elliptic to lanceolate, margins usually coarsely dentate or serrate, rarely subpinnatifid, surfaces pubescent as basal.

Racemes

2–12-flowered, ebracteate, slightly elongated in fruit;

rachis not flexuous, pubescent as stem.

9–28-flowered, ebracteate, paniculate;

rachis not flexuous, pubescent as stem.

Flowers

sepals oblong, 1.5–2.5 mm, pubescent, (trichomes simple and short-stalked, 2–4-rayed);

petals bright yellow, oblanceolate to spatulate, 2–3.5(–4) × 1.5–2 mm;

anthers oblong, 0.5–0.6 mm.

sepals oblong, 2.5–3 mm, pubescent, (trichomes simple and subsessile, 2–4-rayed);

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

anthers oblong, 0.5–0.6 mm.

Fruiting pedicels

divaricate-ascending, straight, 1–5 mm, pubescent, trichomes simple (0.3–0.9 mm) and stalked, 2–5-rayed (0.1–0.5 mm).

horizontal to divaricate-ascending, straight, (4–)6–12(–15) mm, pubescent, trichomes 2–4-rayed.

Fruits

often ovoid, plane, slightly inflated basally (symmetric), (2.5–)3–4(–5) × 1.5–3.5 mm;

valves densely pubescent, trichomes 2–6-rayed, 0.05–0.4 mm, occasionally some simple;

ovules 4–8(–12) per ovary;

style 0.2–0.6(–0.8) mm.

narrowly oblong to elliptic or oblong-lanceolate, often strongly twisted, flattened, 5–11 × 1.5–2.2 mm;

valves pubescent, trichomes subsessile or sessile, 2–4-rayed, 0.07–0.3 mm;

ovules 4–10(–12) per ovary;

style (1)1.5–3(–4) mm, (sparsely pubescent).

Seeds

oblong, 1.2–1.8 × 0.8–1.1 mm.

oblong, 1.2–1.8 × 0.6–0.9 mm.

2n

= 42.

= 16.

Draba novolympica

Draba ramosissima

Phenology Flowering Jun–Aug. Flowering Apr–Jun.
Habitat Alpine crests, open knolls, fellfields, talus, weathered shale, calcareous shale scree, rocky grounds and cliffs, subalpine conifer forests Limestone cliffs and outcrops, shale barrens, rocky wooded areas
Elevation 1500-3700 m (4900-12100 ft) 0-1100 m (0-3600 ft)
Distribution
from FNA
CA; ID; MT; NV; OR; UT; WA; WY; AB; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
DC; KY; MD; NC; TN; VA; WV
[BONAP county map]
Discussion

Draba novolympica is the same taxon that C. L. Hitchcock (1941) and R. C. Rollins (1993) called D. paysonii var. treleasei, and G. A. Mulligan (2002) called D. paysonii. The two are amply distinct and should be recognized as separate species. Draba novolympica is easily distinguished from D. paysonii by having fruit valves pubescent with 2–6-rayed (occasionally some simple) trichomes 0.05–0.4 mm, sepals 1.5–2.5 mm, petals 2–3.5(–4) × 1.5–2 mm, fruits (2.5–)3–4(–5) × 1.5–3.5 mm, styles 0.2–0.6(–0.8) mm, and ovules 1.2–1.8 × 0.8–1.1 mm. By contrast, D. paysonii has fruit valves pubescent with simple and 2-rayed (some 4- or 5-rayed) trichomes (0.2–)0.4–1 mm, sepals 2.8–3.5 mm, petals (4–)5–6 × (1.5–)2–3 mm, fruits (5–)6–9 × (3–)3.5–5 mm, styles (0.6–)0.8–1.2 mm, and ovules 1.7–2.2 × 1–1.4 mm.

Both R. C. Rollins (1993) and N. H. Holmgren (2005b) indicated that Draba novolympica (as D. paysonii var. treleasei) occurs in Alaska and Yukon, but we have not seen any material from there, and it is likely that their records were based on misidentified plants. Previous reports of D. paysonii from Canada (e.g., G. A. Mulligan 1971b) pertain instead to D. novolympica.

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

Source FNA vol. 7, p. 323. FNA vol. 7, p. 332.
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. 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. 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. 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. barbata var. treleasei, D. paysonii var. treleasei Alyssum dentatum, D. dentata, D. ramosissima var. glabrifolia
Name authority Payson & H. St. John: Proc. Biol. Soc. Wash. 43: 113. (1930) Desvaux: J. Bot. Agric. 3: 186. (1815)
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