Silphium asperrimum Hooker; S. asteriscus var. scabrum Nuttall; S. dentatum Elliott var. gatesii (C. Mohr) H. E. Ahles; S. gatesii C. Mohr; S. integrifolium Michaux var. gattingeri L. M. Perry; S. laevigatum Pursh; S. scaberrimum Elliott

Plants 40–150 cm. Leaves: basal caducous; cauline opposite or alternate; faces hirsute, hispid, or scabrous. Paleae puber-ulent to scabrous. Ray florets 8–20. Disc florets 35–110. 2n = 14.

Flowering summer–early fall. Prairies, meadows, open forests, roadsides; 50–1000 m; Ala., Ark., Fla., Ga., Ky., La., Miss., Mo., N.C., Okla., S.C. Tenn., Tex., Va.

The name Silphium asperrimum has been misapplied to S. radula. Based upon examination of a photograph of the type and of the original description, S. asperrimum should be synonymized with S. asteriscus.