The present study was undertaken to provide modern distribution maps and a workable key for the Iowa milkweeds. The genus Asclepias has not been separately studied in Iowa, so far as'' the authors can ascertain. In the most recent Iowa flora, Conard (1951) lists 16 species. In the present work 15 species are recognized. Appreciation is extended to Dr. Robert Thorne and Dr. Richard Pohl for the use of specimens from the herbaria of the State University of Iowa and Iowa State College. In addition, material from the herbarium of Grinnell College has been studied. In all, approximately 1200 sheets of Asclepias were examined.
Proceedings of the Iowa Academy of Science
©1955 Iowa Academy of Science, Inc.
Nicolson, Dan and Russell, Norman H.
"The Genus Asclepias in Iowa,"
Proceedings of the Iowa Academy of Science, 62(1), 211-215.
Available at: https://scholarworks.uni.edu/pias/vol62/iss1/22