Lactuca canadensis is an annual or biennial herb, 0.3 -2.5 m tall, sap milky, white to tan, stem leafy, often waxy-pale (glaucous).
Leaves alternate, entire to lobed, margin toothed or lobed to entire, base narrowed, or sometimes clasping stem or with pointed lobes, blade 10-35 cm long, 1.5-12 cm wide, leaves of basal rosette to 35 cm.
Flowers yellow, all rays, 13-22 per head, bracteate base to 1-1.5 cm tall in fruit, heads numerous; inflorescence branched, July-Sept.
Fruit dry, 1-seeded achenes, blackish, very flat with one vein on each face, to 0.6 cm, with white plume on a narrow beak; seeds eaten by birds, plants eaten by deer (Martin et al. 1951).
Wetland status: FACU-.
Frequency in NYC: Occasional.
Habitat: Open woods, edges, thickets, vacant lots.