Walton, G.B. 1994. Report for field season 1994 status survey for Caltha natans and Sparganium glomeratum in Minnesota. Final report submitted to the Natural Heritage and Nongame Research Program, Minnesota Department of Natural Resources. 9 pp.
The purpose of this study is to relocate historical populations of Caltha natans and Sparganium glomeratum in Minnesota and to also locate new populations of these species. In 1994 field work was done in St. Louis and Carlton counties from May until September under a grant provided through the Conservation Biology Research Program of the Minnesota Department of Natural Resources Natural Heritage Program. At the end of this report is a list giving township, range, and section, landmarks such as roads, number of plants present or area covered, habitat descriptions, and associated species of all observed or collected specimens of S. glomeratum (permit #7131) and C. natans.