Draba stenoloba

Ledebour

Fl. Ross. 1: 154. 1841.

Endemic
Synonyms: Draba acinacis H. St. John Draba hirta var. siliquosa Chamisso & Schlechtendal Draba macouniana Rydberg Draba nemorosa var. stenoloba (Ledebour) M. E. Jones Draba nitida var. praelonga O. E. Schulz Draba oligantha Greene Draba stenoloba var. oligantha (Greene) O. E. Schulz
Treatment appears in FNA Volume 7. Treatment on page 340. Mentioned on page 272, 273, 276, 278, 282, 287, 289, 341.

Biennials or perennials; (short-lived, not cespitose); caudex simple (not fleshy); scapose. Stems often unbranched, (0.2–) 0.4–3 (–3.4) dm, pubescent proximally, usually glabrous distally, rarely sparsely pubescent, trichomes short-stalked, 2–4-rayed, 0.1–0.4 (–0.5) mm. Basal leaves rosulate; petiole (obscure), margin ciliate, (trichomes simple, 0.2–0.4 mm); blade oblanceolate to obovate, 0.4–2.6 (–3.1) cm × 1.5–7 (–10) mm, margins entire or denticulate, (ciliate as petiole), surfaces pubescent, abaxially with short-stalked, 3-rayed or 4-rayed trichomes, 0.1–0.5 mm, adaxially with simple and stalked, 2–4-rayed trichomes, 0.1–0.5 mm. Cauline leaves (0 or) 1 or 2 (3 or 4); sessile; blade elliptic to lanceolate or ovate, margins toothed, surfaces pubescent, abaxially with short-stalked 3-rayed or 4-rayed trichomes, adaxially with simple and short-stalked, 2–4-rayed trichomes. Racemes (2–) 4–10 (–15) -flowered, ebracteate, elongated in fruit; rachis not flexuous, usually glabrous, rarely sparsely pubescent. Fruiting pedicels horizontal to divaricate-ascending, straight, 3–14 (–19) mm (subequaling or shorter than fruit), usually glabrous, rarely pubescent, trichomes 2–4-rayed. Flowers (chasmogamous, petaliferous); sepals (green or purplish), oblong, 1.5–2.5 mm, glabrous or pubescent, (trichomes simple); petals yellow, oblanceolate, 2.5–3.5 × 0.6–1 mm; anthers ovate, 0.25–0.4 mm. Fruits linear or, rarely, linear-elliptic, plane, flattened, (8–) 10–17 (–20) × 1.5–2 mm; valves usually glabrous, rarely sparsely puberulent, trichomes simple; ovules 24–36 per ovary; style 0.01–0.15 mm. Seeds ovoid, 0.9–1 × 0.5–0.6 mm. 2n = 40.


Phenology: Flowering Jun–Jul.
Habitat: Grassy knolls, glacial moraines and creek banks, mesic meadows, alpine thickets
Elevation: 600-2300 m

Distribution

V7 474-distribution-map.gif

Alta., B.C., Yukon, Alaska, Oreg., Wash.

Discussion

Draba stenoloba is occasionally confused with D. albertina, but is easily recognized by having exclusively 2–4-rayed (versus mostly simple) trichomes on stems proximally. It is rarely encountered and apparently confined to the Pacific Northwest. In contrast, D. albertina is common and widespread in the mountains of western North America.

Selected References

None.

Lower Taxa

None.

"elongated" is not a number."thick" is not a number."dm" is not declared as a valid unit of measurement for this property."dm" is not declared as a valid unit of measurement for this property.

... more about "Draba stenoloba"
0.025 cm0.25 mm <br />2.5e-4 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
Ihsan A. Al-Shehbaz +, Michael D. Windham +  and Reidar Elven +
Ledebour +
sessile +  and petiolate +
appendaged +  and unappendaged +
2.6 cm26 mm <br />0.026 m <br /> (3.1 cm31 mm <br />0.031 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
not +  and auriculate +
0.4 cm4 mm <br />0.004 m <br /> (2.6 cm26 mm <br />0.026 m <br />) +
lobed +, toothed +  and entire +
elliptic;lanceolate or ovate +
much smaller +  and reduced +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
urceolate +, campanulate +  and tubular +
scapose +  and simple +
well-developed +
distinct +
well-differentiated +
emarginate +  and entire +
Alta. +, B.C. +, Yukon +, Alaska +, Oreg. +  and Wash. +
600-2300 m +
straight +  and curved +
not winged +  and unappendaged +
connate +  and distinct +
not basally +  and dilated +
actinomorphic +
orange;purple;orange;purple;pink;white;yellow +
spreading +, ascending +  and erect +
linear +, oblanceolate +, spatulate +, obovate +, subsaccate +, not saccate +, oblong +  and ovate +
latiseptate +, twisted +  and sessile +
1.7 cm17 mm <br />0.017 m <br /> (2 cm20 mm <br />0.02 m <br />) +
indehiscent +  and dehiscent +
1 cm10 mm <br />0.01 m <br /> (1.7 cm17 mm <br />0.017 m <br />) +
flattened +  and plane +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Grassy knolls, glacial moraines and creek banks, mesic meadows, alpine thickets +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
dentate +  and entire +
toothed;denticulate;entire +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
2.5mm;3.5mm +
rudimentary +
oblanceolate +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Flowering Jun–Jul. +
trinucleate +  and 3(-11)-colpate +
ebracteate;(2-)4-10(-15)-flowered +
ascending +  and erect +
slender +
not flexuous +
pubescent +  and glabrous +
mucilaginous +
not +  and mucilaginous +
white +, black +, brown +  and yellow +
0.09 cm0.9 mm <br />9.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
persistent +  and caducous +
distinct +
spreading +, ascending +  and erect +
pubescent +  and glabrous +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
reduced +
latiseptate +, twisted +  and sessile +
indehiscent +  and dehiscent +
terete +, plane +, subglobose +, ovoid +, suborbicular +, linear +, oblong +, elliptic +, lanceolate +  and ovate +
latiseptate +, twisted +  and sessile +
indehiscent +  and dehiscent +
terete +, plane +, subglobose +, ovoid +, suborbicular +, linear +, oblong +, elliptic +, lanceolate +  and ovate +
tetradynamous +
procumbent +  and decumbent +
prostrate +  and decumbent +
usually erect +  and ascending +
pubescent +  and glabrous +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
0.001 cm0.01 mm <br />1.0e-5 m <br /> (0.015 cm0.15 mm <br />1.5e-4 m <br />) +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
Draba acinacis +, Draba hirta var. siliquosa +, Draba macouniana +, Draba nemorosa var. stenoloba +, Draba nitida var. praelonga +, Draba oligantha +  and Draba stenoloba var. oligantha +
Draba stenoloba +
species +
simple +, short-stalked +  and stalked +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
cruciform +  and forked +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
coiled +, 1-7-veined +  and veined +
puberulent +  and glabrous +
anastomosing +
scapose +  and not +
1.4 cm14 mm <br />0.014 m <br /> (1.9 cm19 mm <br />0.019 m <br />) +
perennial +  and biennial +
horizontal +  and divaricate-ascending +
pubescent +  and glabrous +
0.3 cm3 mm <br />0.003 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +