Synonyms
Silphium scabrum Moench
Silphium petiolatum Poir.
Silphium perfoliatum f. hornemannii (Schrad. ex DC.) Voss
Silphium perfoliatum f. petiolatum E.J.Palmer & Steyerm.
Silphium hornemannii Schrad. ex DC.
Silphium erythrocaulon Bernh. ex Spreng.
Silphium tetragonum Moench
Resinocaulon perfoliatum Lunell
Silphium conjunctum Willd.
Silphium perfoliatum var. conjunctum (Willd.) Pursh
Silphium quadrangulum Hedw.