During the summer of 1914 an unusual specimen of Ambrosia was noted which seems likely to have been a hybrid. The plant grew by the roadside on bottom land a few hundred yards from the Butler's Landing Bridge a couple of miles north of Iowa City. It stood near the foot of the long hill beyond the bridge and near the margin of the lowland. The location in the edge of the grading was favorable in that its soil received the wash from the higher land. The plant was surrounded by various weeds and among them and nearby were several specimens of the supposed parent species, Ambrosia trifida L., and Ambrosia artemisiifobia L.
Proceedings of the Iowa Academy of Science
©1915 Iowa Academy of Science, Inc.
Wylie, Robert Bradford
"A Hybrid Ragweed,"
Proceedings of the Iowa Academy of Science, 22(1), 127-128.
Available at: https://scholarworks.uni.edu/pias/vol22/iss1/16