Draba verna

Linnaeus

Sp. Pl. 2: 642. 1753.

Common names: Whitlow grass whitlow wort
WeedyIntroduced
Synonyms: Draba boerhaavii (H. C. Hall) Raus Draba praecox Steven Draba verna var. aestivalis Lejeune Draba verna var. boerhaavii H. C. Hall Erophila boerhaavii (Steven) de Candolle Erophila krockeri (Linnaeus) L. Chevallier Erophila praecox Erophila verna Erophila verna subsp. praecox (Steven) Walters
Treatment appears in FNA Volume 7. Treatment on page 345. Mentioned on page 270, 271.
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Annuals; scapose. Stems (few-to-many from base), unbranched, (0.2–) 0.5–2 (–3) dm, pubescent proximally, glabrous distally, trichomes simple and 2 (–4) -rayed, 0.1–0.4 mm. Basal leaves rosulate; petiolate; blade obovate, spatulate, oblanceolate, lanceolate, oblong, or, rarely, linear, 0.2–1.8 (–3) cm × (0.5–) 1–5 (–10) mm, margins entire or 1–5-toothed on each side, surfaces pubescent with simple or stalked, 2–4-rayed trichomes, 0.1–0.5 mm. Cauline leaves 0. Racemes 4–20 (–30) -flowered, ebracteate, usually considerably elongated in fruit; rachis usually flexuous, glabrous. Fruiting pedicels divaricate to ascending, straight or slightly curved upward, (2–) 5–20 (–35) mm, glabrous. Flowers: sepals (green or purplish), oblong, 1–2.5 mm, glabrescent or pubescent, (trichomes simple or 2-rayed); petals white, deeply 2-fid, (1.5–) 2–4.5 (–6) × 1–2 mm; anthers ovate, 0.2–0.4 mm. Fruits obovate, oblanceolate, lanceolate, elliptic, oblong, or linear, plane, flattened, (2.5–) 4–9 (–12) × 1.5–2.5 (–3.5) mm; valves glabrous; ovules (20–) 32–70 (–84) per ovary; style 0.02–0.2 mm. Seeds ovoid (slightly flattened), 0.3–0.6 (–0.8) × 0.2–0.4 mm. 2n = 14, 16, 20, 24, 28, 30, 32, 34, 36, 38, 40, 52, 54, 58, 60, 64.


Phenology: Flowering Feb–May.
Habitat: Cedar glades, lawns, fields, pastures, waste places, grassy hillsides, disturbed sites, roadsides
Elevation: 0-2500 m

Distribution

V7 483-distribution-map.gif

Introduced; Alta., B.C., N.B., Ont., Que., Ala., Ark., Calif., Conn., Del., D.C., Ga., Idaho, Ill., Ind., Iowa, Ky., Maine, Md., Mass., Mich., Miss., Mo., Mont., Nev., N.H., N.J., N.Y., N.C., Ohio, Oreg., Pa., R.I., S.C., Tenn., Utah, Vt., Va., Wash., W.Va., Wyo., Europe, Asia, nw Africa, also in Central America, South America, Australia

Discussion

Draba verna represents a highly variable and taxonomically difficult complex within which species, subspecies, varieties, and forms have been named (O. E. Schulz 1927); only those synonyms pertaining to North America are listed above. Most of the taxonomic difficulties are the results of disploidy, autogamy, and hybridization. The morphological extremes are connected by intermediate forms in every conceivable character. Furthermore, there appears to be no correlation between morphology, cytology, geography, and ecology to support the division of this complex into meaningful taxa. A complex cytological picture was presented by Ø. Winge (1940), including the highest count of 2n = 94, which has not been confirmed by subsequent botanists.

Erophila vulgaris de Candolle is an illegitimate name for Draba verna.

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 verna"
64 +, 60 +, 58 +, 54 +, 52 +, 40 +, 38 +, 36 +, 34 +, 32 +, 30 +, 28 +, 24 +, 20 +, 16 +  and 14 +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
Ihsan A. Al-Shehbaz +, Michael D. Windham +  and Reidar Elven +
Linnaeus +
appendaged +  and unappendaged +
1.8 cm18 mm <br />0.018 m <br /> (3 cm30 mm <br />0.03 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
not +  and auriculate +
0.2 cm2 mm <br />0.002 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
lobed +, toothed +  and entire +
oblong;lanceolate;oblanceolate;spatulate;obovate +
much smaller +  and reduced +
0.1 cm1 mm <br />0.001 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
urceolate +, campanulate +  and tubular +
branched +  and simple +
sessile +  and petiolate +
well-developed +
distinct +
well-differentiated +
Whitlow grass +  and whitlow wort +
emarginate +  and entire +
Alta. +, B.C. +, N.B. +, Ont. +, Que. +, Ala. +, Ark. +, Calif. +, Conn. +, Del. +, D.C. +, Ga. +, Idaho +, Ill. +, Ind. +, Iowa +, Ky. +, Maine +, Md. +, Mass. +, Mich. +, Miss. +, Mo. +, Mont. +, Nev. +, N.H. +, N.J. +, N.Y. +, N.C. +, Ohio +, Oreg. +, Pa. +, R.I. +, S.C. +, Tenn. +, Utah +, Vt. +, Va. +, Wash. +, W.Va. +, Wyo. +, Europe +, Asia +, nw Africa +, also in Central America +, South America +  and Australia +
0-2500 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 +
pubescent +  and glabrescent +
0.1 cm1 mm <br />0.001 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
latiseptate +, twisted +  and sessile +
0.9 cm9 mm <br />0.009 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
indehiscent +  and dehiscent +
0.4 cm4 mm <br />0.004 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
flattened +, plane +, linear +, oblong +, elliptic +, lanceolate +, oblanceolate +  and obovate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
Cedar glades, lawns, fields, pastures, waste places, grassy hillsides, disturbed sites, roadsides +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
dentate +  and entire +
1-5-toothed;entire +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
2mm;4.5mm +
rudimentary +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Flowering Feb–May. +
trinucleate +  and 3(-11)-colpate +
ebracteate;4-20(-30)-flowered +
ascending +  and erect +
slender +
2 cm20 mm <br />0.02 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
curved +, straight +  and flexuous +
mucilaginous +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
not +  and mucilaginous +
white +, black +, brown +  and yellow +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
persistent +  and caducous +
distinct +
spreading +, ascending +  and erect +
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 +
Weedy +  and Introduced +
tetradynamous +
procumbent +  and decumbent +
prostrate +  and decumbent +
usually erect +  and ascending +
glabrous +  and pubescent +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
0.002 cm0.02 mm <br />2.0e-5 m <br /> (0.02 cm0.2 mm <br />2.0e-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 boerhaavii +, Draba praecox +, Draba verna var. aestivalis +, Draba verna var. boerhaavii +, Erophila boerhaavii +, Erophila krockeri +, Erophila praecox +, Erophila verna +  and Erophila verna subsp. praecox +
Draba verna +
species +
stalked +  and simple +
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 +
anastomosing +
pubescent +  and glabrous +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +