I recently had the great fortune to visit the confluence of the Passadumkeag River, Cold Stream, and Ayers Brook - a National Natural Landmark found just east of the town in northern Penoboscot County… One of thirteen Maine sites known to harbor the Tomah mayfly - long thought extirpated, but rediscovered in the late 1970’s . Also home of a rare bulrush, Scirpus steinmetzii... Botanists have found the bulrush only along the Passadumkeag River and are uncertain whether it is a species evolving over time, or a hybrid of two other species.
More information from the National Parks Service: Click Here