Coefficient of Conservatism:
Coefficient of Wetness:
A. A. Reznicek
By far our commonest species in Michigan, probably occurring in almost every pond and lake in the state, as well as many rivers and streams. It occurs in the Great Lakes system as well as inland and in bogs. Collections are reported at depths to 5 m, but the species has been found as deep as 8.2 m. An annual that fruits abundantly, the plant is an important duck food.
This is an exceedingly variable species, ranging from short, much-branched, condensed and bushy extremes to plants with stout stems, long internodes, and wider leaves; the differences are probably due in large part to ecological factors.