The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Draba, tall Draba, tall whitlow-grass, tall whitlow-grass Draba

Lake Tahoe Draba, Tahoe Draba

Habit Annuals or perennials; (short-lived); caudex simple or branched; not scapose. Perennials; (loosely cespitose); caudex branched (somewhat surculose, with persistent leaf bases, branches sometimes terminating in sterile rosettes); scapose.
Stems

branched or unbranched, (0.5–)0.8–3.2(–3.8) dm, pubescent throughout, trichomes 3–5-rayed, 0.1–0.4 mm, with simple and 2-rayed ones, 0.4–1 mm.

unbranched, 0.3–1.1 dm, glabrous throughout or sparsely pubescent proximally, trichomes (2–)4-rayed, 0.1–0.3 mm.

Basal leaves

rosulate;

subsessile;

petiole base ciliate, (trichomes simple and 2-rayed, 0.2–0.8 mm);

blade oblanceolate, (0.7–)1–3.5(–4.5) cm × 1.5–7(–9) mm, margins usually dentate, rarely entire, surfaces pubescent, abaxially with stalked, 3–6-rayed trichomes, 0.1–0.5 mm, adaxially with stalked, 3–5-rayed, 0.1–0.6 mm, and simple ones, to 0.8 mm.

rosulate; petiolate;

petiole obsolete, margin rarely ciliate proximally;

blade (somewhat fleshy), broadly obovate to suborbicular or spatulate, 0.4–1.4(–1.7) cm × (2–)3–6(–7) mm, margins entire, surfaces pubescent, trichomes stalked, cruciform, and 2-, 3-, or 5-rayed, 0.2–0.6 mm.

Cauline leaves

(1 or) 2–5(–9);

sessile;

blade ovate to lanceolate, margins dentate or entire, surfaces pubescent as basal.

0 (or 1, as a bract).

Racemes

(5–)8–30(–37)-flowered, ebracteate, elongated in fruit;

rachis not flexuous, pubescent as stem.

(5–)8–20(–27)-flowered, usually ebracteate, rarely proximalmost flowers bracteate, elongated in fruit;

rachis not flexuous, glabrous.

Flowers

(late-season ones petaliferous);

sepals ovate, 1.7–2.5 mm, pubescent, (trichomes simple and stalked, 2-rayed);

petals white, oblanceolate to spatulate, 2.8–3.5(–4) × 0.8–1.2 mm;

anthers ovate, 0.2–0.3 mm.

sepals oblong, 3–4 mm, glabrous or sparsely pubescent, (trichomes subapical, short-stalked, 2–4-rayed);

petals bright yellow, oblanceolate, 5–7 × 1.5–2.5 mm;

anthers ovate, 0.5–0.6 mm.

Fruiting pedicels

divaricate-ascending to ascending or suberect (not appressed to rachis), straight, (3–)4–10(–12) mm, pubescent, trichomes 3–5-rayed (0.1–0.4 mm), and sometimes simple.

horizontal to divaricate-ascending, straight or curved upward, 3–9 mm, glabrous.

Fruits

(erect, not appressed to rachis) lanceolate to linear-lanceolate, plane, flattened, (5–)7–12(–15) × 1.5–2.5(–3) mm;

valves puberulent, trichomes simple and short-stalked, 2–4-rayed, 0.05–0.25 mm;

ovules (24–)30–52 per ovary;

style 0.03–0.1(0.15) mm.

lanceolate-ovate to broadly ovate or oblong, slightly twisted or plane, strongly flattened, 5–11(–14) × (3.5–)4–6 mm;

valves glabrous or, rarely, puberulent, trichomes simple and short-stalked, 2- or 3-rayed, 0.05–0.3 mm;

ovules 12–18 per ovary;

style 0.2–1.6(–2) mm.

Seeds

oblong, 0.8–1.1 × 0.5–0.6 mm, (often apiculate).

(winged), ovate, 1.8–2.8 × 1.2–2 mm; (wing 0.5–1 mm wide).

2n

= 56.

= 40.

Draba praealta

Draba asterophora

Phenology Flowering Jun–Aug. Flowering Jun–Aug.
Habitat Rocky pine slopes, subalpine areas, alpine meadows, grassy volcanic ridges, woodlands, damp rocky areas, limestone talus, shale cliffs, steep hillsides Granitic rock outcrops, talus, gravelly soil
Elevation 1200-2900 m (3900-9500 ft) 2600-3300 m (8500-10800 ft)
Distribution
from FNA
CA; ID; MT; NV; OR; WA; WY; AB; BC; NT; YT; e Asia (Russian Far East [Chukchi Peninsula])
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; NV
[BONAP county map]
Discussion

Morphological and chromosomal evidence (M. D. Windham, unpubl.) suggests that Draba praealta may be an allopolyploid originating through hybridization between D. albertina and D. cana. Both R. C. Rollins (1993) and N. H. Holmgren (2005b) placed D. lonchocarpa var. dasycarpa in the synonymy of D. lonchocarpa. G. A. Mulligan (1974) indicated that the type of var. dasycarpa does not belong to that species and he correctly annotated its isotype (Macoun 64454, CAN) as D. praealta. Mulligan (1976) and Rollins indicated that D. praealta occurs in Alaska, but we have not seen unequivocal material from the state.

We have not seen the material on which A. E. Katenin and V. V. Petrovsky (1995) based their record from the Russian Far East.

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

C. L. Hitchcock (1941) and R. C. Rollins (1993) divided Draba asterophora into two varieties based on minor differences in style and fruit lengths. These do not appear to define genetically discrete taxa. The species apparently is restricted to El Dorado County, California, and the Carson Range in Washoe County, Nevada.

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

Source FNA vol. 7, p. 331. FNA vol. 7, p. 294.
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. 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. 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. cascadensis, D. columbiana, D. dolichopoda, D. lapilutea, D. lonchocarpa var. dasycarpa, D. praealta var. yellowstonensis, D. yellowstonensis D. asterophora var. macrocarpa
Name authority Greene: Pittonia 3: 306. (1898) Payson: Amer. J. Bot. 4: 263. (1917)
Web links