Growing in what looked like a former cow pond, now mostly grown in.
There are a few species of this aquatic fern in the state. I need to figure out how to identify them.
Azolla (mosquito fern, duckweed fern, fairy moss, water fern) is a genus of seven species of aquatic ferns, the only genus in the family Azollaceae. They are extremely reduced in form and specialized, looking nothing like conventional ferns but more resembling duckweed or some mosses.