In 1935 I found this species to be common in the artificial lake in Shakamak State Park, Sullivan County. I did not investigate how extensively it was established but the border was well stocked with it as far as I traversed it. This lake is artificial and was made only a few years ago. No one seems to know when or how it got its start in the lake. I was informed by a workman that aquatic plants had been collected from the sloughs along Eel River and put into the lake. The interesting thing is that this species has so well adapted itself to its new habitat that it now grows abundantly on the shore of a lake which a few years ago was a poor, fallow field. Since no effort will be made to exterminate it, it is established in this place.