Page authors: Don Knoke, David Giblin
Lactuca serriola
prickly lettuce

Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to the Atlantic Coast.

Habitat: Roadsides, fields, forest edge, wastelots, and other disturbed places.

Flowers: July-September

Origin: Introduced from Europe

Growth Duration: Annual, Biennial

Conservation Status: Not of concern

Pollination: Bees


Winter annual or biennial, 3-15 dm. tall, glabrous, with milky juice.


Leaves prickly on the midrib beneath and on the margins, pinnately lobed (or entire in one variety), twisted at the base to lie in a vertical plane, sagittate-clasping, 5-30 cm. long and 1-10 cm. wide.


Heads numerous, 13-27 flowered, the flowers yellow, all ligulate; involucre 10-15 mm. high, cylindric but broadening at the base, the bracts imbricate; pappus of white capillary bristles.


Achenes gray or yellowish, the body 3-4 mm. long and a third as wide, compressed, prominently several-nerved on each face, with fine spines above, the beak as long to twice as long as the body.

Accepted Name:
Lactuca serriola L.
Publication: Cent. Pl. II. 29. 1756.

Synonyms & Misapplications:
Lactuca scariola L. var. integrata Gren. & Godr.
Lactuca scariola L. var. scariola
Additional Resources:

PNW Herbaria: Specimen records of Lactuca serriola in the Consortium of Pacific Northwest Herbaria database

WA Flora Checklist: Lactuca serriola checklist entry

OregonFlora: Lactuca serriola information

E-Flora BC: Lactuca serriola atlas page

CalPhotos: Lactuca serriola photos

56 photographs:
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