*Sonchus asper (L.) Hillglaucescens (Jord.) Ball

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