Lactuca virosa

Bitter lettuce

Family: Asteraceae · Type: biennial · Not Native

Bitter lettuce is a naturalized biennial found in northern San Francisco Bay and northern South Coast Ranges on disturbed, shrubby, and wooded slopes at elevations below 600 meters. Flowering from June to August, this plant produces pale yellow flowers in clusters with heads 3 to 4 centimeters in diameter. Growing 0.6 to 2 meters tall with an erect stem that is glabrous or bristly near the base, it forms a persistent basal rosette of oblanceolate to obovate leaves. Its leaves range from dentate to shallowly lobed, with lower leaves having winged petioles and upper leaves widely clasping the stem with prickly-bristly midveins. The fruit has 5 to 9 ribs on each face, with a dark body, wing-margined edges, and a white beak approximately equal in length to the body.

Habitat: Disturbed, shrubby and wooded slopes

Bloom period: Jun-Aug

Elevation: < 600 m

Bioregions: SnFrB, n SCoRO

Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Jepson eFlora, Cal-IPC, and more.