Lactuca serriola

Linnaeus

Cent. Pl. II, 29. 1756.

IntroducedIllustrated
Treatment appears in FNA Volume 19. Treatment on page 262. Mentioned on page 260.

Annuals (perhaps persisting), (15–) 30–70 (–100+) cm. Leaves on proximal 1/2–3/4 of each stem; blades of undivided cauline leaves usually ± oblong, sometimes obovate to lanceolate, margins denticulate, usually prickly, midribs usually prickly-setose, rarely smooth. Heads in paniculiform arrays. Involucres 9–10 (–12) mm. Phyllaries usually reflexed in fruit. Florets 12–20; corollas yellow, usually deliquescent. Cypselae: bodies pale grayish to tan, ± flattened, oblanceolate, 2.5–3.5 mm, beaks ± filiform, 2.5–4 mm, faces (3–) 5–9-nerved; pappi white, (3–) 4–5 mm. 2n = 18.


Phenology: Flowering (May–)Jul–Sep(–Oct).
Habitat: Roadsides, disturbed sites
Elevation: 10–2300 m

Distribution

V19-356-distribution-map.gif

Introduced; Alta., B.C., Man., N.B., N.S., Ont., P.E.I., Que., Sask., Ala., Ariz., Ark., Calif., Colo., Conn., Del., D.C., Fla., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis., Wyo., Europe, also nearly worldwide

Discussion

The name Lactuca scariola Linnaeus is evidently illegitimate; it is a superfluous name based on the same type as L. serriola. Plants included here in L. serriola with most leaf blades obovate to lanceolate (not lobed) and lacking prickles on midribs have been called L. scariola subsp. or var. integrata or L. serriola forma integrifolia or L. serriola var. integrata.

Selected References

None.

Lower Taxa

None.

"fine" is not a number.

... more about "Lactuca serriola"
obtuse;acute +
scarious +
ovate +  and lanceolate +
paniculiform +
indeterminate +  and determinate +
John L. Strother +
Linnaeus +
decurrent +
filiform +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
compound +  and simple +
lanceolate;oblanceolate linear or filiform +
pale grayish +  and tan +
tuberculate +, rugose +, muricate +  and smooth +
oblanceolate;flattened +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
deltate;lanceolate +
filiform +
simple +, barbellulate +  and nearly smooth +
zygomorphic +, actinomorphic +  and (3-)5-merous +
fuscous +  and white +
subtending +
0.005 cm0.05 mm <br />5.0e-5 m <br /> (0.02 cm0.2 mm <br />2.0e-4 m <br />) +
purplish +  and blackish +
tapered +, beaked +, flattened +, obcompressed +, compressed +, prismatic +, fusiform +, ellipsoid +, columnar +  and clavate +
Alta. +, B.C. +, Man. +, N.B. +, N.S. +, Ont. +, P.E.I. +, Que. +, Sask. +, Ala. +, Ariz. +, Ark. +, Calif. +, Colo. +, Conn. +, Del. +, D.C. +, Fla. +, Ga. +, Idaho +, Ill. +, Ind. +, Iowa +, Kans. +, Ky. +, La. +, Maine +, Md. +, Mass. +, Mich. +, Minn. +, Miss. +, Mo. +, Mont. +, Nebr. +, Nev. +, N.H. +, N.J. +, N.Mex. +, N.Y. +, N.C. +, N.Dak. +, Ohio +, Okla. +, Oreg. +, Pa. +, R.I. +, S.C. +, S.Dak. +, Tenn. +, Tex. +, Utah +, Vt. +, Va. +, Wash. +, W.Va. +, Wis. +, Wyo. +, Europe +  and also nearly worldwide +
10–2300 m +
(3-)5-9-nerved +
rugulose +
winged +  and beaked +
dispersed +
Roadsides, disturbed sites +
in corymbiform to paniculiform arrays +  and singly +
indeterminate +
each +  and sessile +
1 cm10 mm <br />0.01 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
campanulate;cylindric +
0.9 cm9 mm <br />0.009 m <br /> (1 cm10 mm <br />0.01 m <br />) +
petiolate +  and sessile +
cauline +  and basal +
denticulate +
prickly-setose +
2-carpellate +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
persistent +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Flowering (May–)Jul–Sep(–Oct). +
connate +  and distinct +
5 +  and 13 +
Cent. Pl. II, +
flat;convex +
1 +  and 9 +
exalbuminous +
Introduced +  and Illustrated +
hairy +  and glabrous +
appendaged +  and truncate +
papillate +
Undefined tribe Lactuceae +
Lactuca serriola +
species +
70 cm700 mm <br />0.7 m <br /> (100 cm1,000 mm <br />1 m <br />) +
30 cm300 mm <br />0.3 m <br /> (70 cm700 mm <br />0.7 m <br />) +
shrub +  and subshrub +