Annual sowthistle (Sonchus oleraceae) initially forms a rosette of deeply lobed foliage. Rosettes emerge mid winter, and flowering stems emerge from the rosettes in late winter or early spring.

Rosettes grow up to 14 inches in diameter.

Annual sowthistle and prickly sowthistle (Sonchus asper) are both common in Oregon's Willamette Valley. Below, prickly sowthistle is on the left and annual sowthistle on the right.

Annual sowthistle eventually forms an eradic, highly branched, and somewhat columnar habit. Plants grow up to 4 feet in height.

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