Monography of the Genus Silphium : I. Silphium composium Michaux (Compositae)

Author Institution: Biology Department, State University of New York College at Buffalo, Buffalo, New York 14222Silphium compositum, a polymorphic species of southeastern United States, is recognized to consist of the following subspecies: ssp. compositum, ssp. reniforme, ssp. venosum, and ssp. ovatifolium. The subspecies are distinguished primarily by leaf and achene characters, and are sympatric in some areas. Descriptions, synonomy, distribution maps and citation of representative specimens of the taxa are included