Crepis biennis

Linnaeus

Sp. Pl. 2: 807. 1753.

Common names: Rough hawksbeard
Introduced
Treatment appears in FNA Volume 19. Treatment on page 227. Mentioned on page 223, 232.

Biennials, 20–120 cm (taproots branched). Stems 1, erect, slender to robust, branched proximally or near middles, ± setulose or glabrescent. Leaves basal and cauline; petiolate (at least basal); blades oblanceolate to runcinate, 5–25 × 1.5–7.5 cm, margins pinnately lobed or dentate (terminal lobes triangular), apices ± acute, faces slightly scabrous (hairs yellow, fine). Heads 12–14, in simple or compound, corymbiform arrays. Calyculi of 7–9, lance-linear, glabrous or tomentulose bractlets 3–6 mm. Involucres campanulate, 8–13 × 5–9 mm. Phyllaries 10–17 (pale to dark green or nearly black) linear-lanceolate, 10–11 mm, (margins scarious) apices acute to obtuse (ciliate), abaxial faces ± canescent-tomentose, adaxial often with yellowish or black, appressed hairs. Florets 30–100; corollas yellow, 12–18 mm. Cypselae yellowish or reddish-brown, fusiform, 4–7 mm, apices narrowed (not beaked), ribs 13–20; pappi white, 5–7 mm (somewhat unequal). 2n = 40.


Phenology: Flowering Jun–Aug.
Habitat: Meadows and fields
Elevation: 500–1200 m

Distribution

V19-282-distribution-map.gif

Introduced; Nfld. and Labr. (Nfld.), Mich., N.Y., Ohio, Pa., Va., Vt., Europe

Discussion

Crepis biennis is recognized by its biennial habit, pinnately lobed leaves with triangular lobes, and relatively short hairs on the adaxial faces of the phyllaries. It has been reported from Newfoundland but apparently does not persist there.

Selected References

None.

Lower Taxa

None.

"fine" is not a number.

... more about "Crepis biennis"
canescent-tomentose +
with appressed hairs +  and glabrous +
narrowed;acute;obtuse +
scarious +
ovate +  and lanceolate +
corymbiform +, compound +  and simple +
indeterminate +  and determinate +
David J. Bogler +
Linnaeus +
runcinate +, lyrate +, lanceolate +  and linear or spatulate +
decurrent +
compound +  and simple +
5 cm50 mm <br />0.05 m <br /> (25 cm250 mm <br />0.25 m <br />) +
oblanceolate;runcinate +
1.5 cm15 mm <br />0.015 m <br /> (7.5 cm75 mm <br />0.075 m <br />) +
tuberculate +, rugose +, muricate +  and smooth +
setose +, tomentulose +  and glabrous +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
filiform +
tomentulose +  and glabrous +
lobing +, entire +  and lobed +
Rough hawksbeard +
zygomorphic +, actinomorphic +  and (3-)5-merous +
1.2 cm12 mm <br />0.012 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
reddish-brown +  and yellowish +
Nfld. and Labr. (Nfld.) +, Mich. +, N.Y. +, Ohio +, Pa. +, Va. +, Vt. +  and Europe +
500–1200 m +
hispidulous +  and glabrous +
winged +  and beaked +
dispersed +
Meadows and fields +
black +  and yellowish +
indeterminate +
each +  and sessile +
0.4 cm4 mm <br />0.004 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
campanulate +
0.5 cm5 mm <br />0.005 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
cauline +  and basal +
toothed +
dentate +  and entire +
green +  and yellowish +
dentate +  and lobed +
2-carpellate +
persistent +
connate +  and distinct +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
Flowering Jun–Aug. +
connate +  and distinct +
10 +  and 17 +
1 cm10 mm <br />0.01 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
hairy +  and glabrous +
convex;flat +
13 +  and 20 +
spiculate-roughened +
exalbuminous +
Introduced +
near middles +  and branched +
glabrescent +  and setulose +
slender +
appendaged +  and truncate +
papillate +
Undefined tribe Lactuceae +
Crepis biennis +
species +
taprooted +  and rhizomatous +
20 cm200 mm <br />0.2 m <br /> (120 cm1,200 mm <br />1.2 m <br />) +
shrub +  and subshrub +
11 +, 6 +, 5 +, 4 +  and 3 +