Sometime previous to the spring of 1916 Professor Hughes of the Farm Crops Department of the Iowa State College found in the experimental plots of the common white sweet clover (Melilotus alba (L) Lam), a form which produced an annual root and died at the close of the season.
Proceedings of the Iowa Academy of Science
©1918 Iowa Academy of Science, Inc.
Pammel, L. H. and King, Charlotte M.
"An Annual White Sweet Clover,"
Proceedings of the Iowa Academy of Science, 25(1), 249-257.
Available at: https://scholarworks.uni.edu/pias/vol25/iss1/27