Page authors: Don Knoke, David Giblin
Lactuca canadensis
Canadian wild lettuce, Florida blue lettuce

Distribution: Occurring in scattered locations on both sides of the Cascades crest; Yukon Territory to California, east across North America to the Atlantic Coast.

Habitat: Fields, roadsides, disturbed forest edge, wastelots, and other disturbed places.

Flowers: July-September

Origin: Introduced from central and eastern North America

Growth Duration: Annual, Biennial

Conservation Status: Not of concern

Pollination: Bees, flies, beetles, wasps


Annual or biennial, 3-25 dm. tall, usually glabrous and often glaucous, the juice milky.


Basal and lower cauline leaves 10-35 cm. long and 1.5-12 cm. wide, entire to pinnately lobed.


Heads numerous, 13-22 flowered, the flowers yellow, all ligulate; involucre 10-15 mm. high, cylindric but broadening at the base, the bracts imbricate; pappus bristles 5-7 mm. long, white.


Achenes blackish, very flat, with a median nerve on each face, 4.5-6.5 mm. long including the slender beak, which may be as long as the body.

Accepted Name:
Lactuca canadensis L.
Publication: Sp. Pl. 2: 796. 1753.

Synonyms & Misapplications:
(none provided)
Additional Resources:

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

WA Flora Checklist: Lactuca canadensis checklist entry.

OregonFlora: Lactuca canadensis information.

E-Flora BC: Lactuca canadensis atlas page.

CalPhotos: Lactuca canadensis photos.

USDA Plants: Lactuca canadensis information.

2 photographs:
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