The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

prickly lettuce

Habit Annuals (perhaps persisting), (15–)30–70(–100+) cm.

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.


9–10(–12) mm.



corollas yellow, usually deliquescent.


usually reflexed in fruit.


in paniculiform arrays.


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.


= 18.

Lactuca serriola

Phenology Flowering (May–)Jul–Sep(–Oct).
Habitat Roadsides, disturbed sites
Elevation 10–2300 m (0–7500 ft)
from FNA
AL; AR; AZ; CA; CO; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NS; ON; PE; QC; SK; Europe [Introduced in North America; also introduced nearly worldwide]
[WildflowerSearch map]
[BONAP county map]

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.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 19, p. 262.
Parent taxa Asteraceae > tribe Cichorieae > Lactuca
Sibling taxa
L. biennis, L. canadensis, L. floridana, L. graminifolia, L. hirsuta, L. ludoviciana, L. saligna, L. sativa, L. virosa
Name authority Linnaeus: Cent. Pl. II, 29. (1756)
Web links