Coefficient of Conservatism:
Coefficient of Wetness:
First collected in Michigan in 1938 in Ogemaw Co., and appears to be somewhat aggressive. Local in lakes at depths to 1.2 m, and in the marshes of Lake Erie.
Presumably introduced; but with an uncertain native range, see Stuckey (1985) for more information. In one collection from 6–9 dm of water in Peach Lake, Ogemaw Co., the leaves are as long as 12 cm, and in some cases almost entire, with normal shorter toothed leaves also occurring.