Silphium terebinthinaceum var. pinnatifidum

Leaves pinnately lobed (lobes to 13, sinuses relatively shallow to deep, sometimes almost to midrib; ultimate margins entire or toothed). 2n = 14.

Flowering mid summer-early fall. Wet or dry prairies, fens, open, disturbed sites; 100-500 m; Ala., Ga., Ill., Ky., Mich., Ohio, Tenn.