Sonchus L.
Cypselas brown, with narrow wings or not winged. Involucres 5–6 mm diam. Sonchus
Leaves leathery, stiff. Cypselas ribbed
Leaves with spinose margins, pinnatifid to pinnatisect, oblanceolate to lanceolate, up to 20 cm long and 7 cm wide. Heads 5–6 mm diam. Annual or biennial herb up to 1 m high. Widespread. Weed of cultivation and waste places. Introd. from Europe. Fl. most of the year. Prickly Sowthistle Sonchus asperglaucescens
Leaves without spinose margins, shallowly sinuate-pinnatifid to entire, oblanceolate, up to 30 cm long and 3 cm wide. Heads 10–20 mm diam. Annual or biennial herb up to 1 m high. Coast. Margins of lakes and creeks. Fl. most of the year. Native Sowthistle Sonchus hydrophilus