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 introduced 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.

... more about "Lactuca serriola"
John L. Strother +
Linnaeus +
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 introduced nearly worldwide. +
10–2300 m +
Roadsides, disturbed sites +
Flowering (May–)Jul–Sep(–Oct). +
Cent. Pl. II, +
Introduced +  and Illustrated +
Undefined tribe Lactuceae +
Lactuca serriola +
species +