Prickly lettuce (Lactuca serriola)

Synonyms: Lactuca scariola

Common Names: China lettuce, wild lettuce

Description: Introduced to North America in the late 1890s as a possible seed contaminant.

Habit: Annual or biennial herb that can grow to about 6 feet (1.8 m) tall.

Leaves: Stem leaves are alternate, egg-shaped, smooth or toothed, 2-14 inches long and become smaller up the stem. Conspicuous, white midvein with the underside of vein covered with small spines. Mature leaves are egg-shaped, deeply lobed or unlobed with bristly edges.

Stems: Erect, growing to about 6 feet tall. Smooth or having bristly hairs.

Flowers: Numerous, pale-yellow in color, stalked or stalkless, borne at the end of branches that extend outward. Resembles dandelion follows.

Fruit and seeds: Small, about 3 mm. long, single seeded, lance shaped, flattened, with barbed ribs, attached to a slender stalk that ends in a tuft of white hairs.

Habitat: Native to the Mediterranean. Can be found in grasslands, wetlands, ditches, fields, croplands, orchards, vineyards, landscaped areas, roadsides and disturbed areas.

Reproduction: By seed.

Similar species: Willowleaf lettuce (Lactuca saligna), common sowthistle (Sonchus oleraceus), field sowthistle (Sonchus arvensis), Spiny sowthistle (Sonchus asper)

Credits: The information provided in this factsheet was gathered from the University of California Agriculture & Natural Resources IPM Program.

Individual species images that appear with a number in a black box are courtesy of the Bugwood.org network (http://www.invasive.org).Individual photo author credits may not be included due to the small display size of the images and subsequent difficulty of reading the provided text. All other images appear courtesy of Google (http://images.google.com).

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