Lactuca serriola
Lactuca graminifolia
prickly lettuce
grass-leaf lettuce
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.
on proximal 1/3–1/2 of each stem;
blades of undivided cauline leaves spatulate to lance-linear, margins entire or denticulate, midribs sometimes setose.
9–10(–12) mm.
12–20+ mm.
12–20;
corollas yellow, usually deliquescent.
15–20+;
corollas bluish to purplish, usually deliquescent.
usually reflexed in fruit.
usually reflexed in fruit.
in paniculiform arrays.
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.
bodies brown (often mottled), ± flattened, elliptic, 5–6 mm, beaks ± filiform, 2–4 mm, faces 1(–3)-nerved;
pappi white, 5–9 mm.
= 18.
= 34.
Lactuca serriola
Lactuca graminifolia
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.)
Plants in the western populations of Lactuca graminifolia have been called L. graminifolia var. arizonica McVaugh; they may belong to a Mexican species.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
- Local floras:
BC, 
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
Go Botany, 
IL Wildflowers, 
KS Wildflowers, 
LA Plants, 
MD Biodiversity, 
MI Flora, 
MN Wildflowers, 
MO Plants, 
PNW Herbaria, 
SW CO Wildflowers, Turner Photog. 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
