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.

From Flora of Indiana (1940) by Charles C. Deam

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.

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Indiana Coefficient of Conservatism: C = null, non-native

Wetland Indicator Status: N/A