Plants 50-150 cm. Leaves: basal persistent or caducous; cauline mostly opposite; faces glabrous or sparsely hairy. Paleae puberulent. Ray florets 12-17. Disc florets 35-130.

Flowering mid summer-early fall. Fields, roadsides, disturbed areas; 100-900 m; Ala., Ga., Ky., La., Miss., N.C., S.C., Tenn., Va., W.Va.

Silphium confertifolium has persistent basal leaves and a diminutive stature that is due to environmental variation; it is best included in S. asteriscus var. latifolium.

This is a glabrate form of the species and is not well marked. Some specimens will have most of the leaves glabrous above and one or more scabrous above. I have this form from Crawford, Decatur, and Washington Counties.