Gray/Cope's Gray tree frog

I would say it's either a gray tree frog (Hyla versicolor) or a Cope's gray tree frog (Hyla chrysoscelis). The two are very closely related and practically impossible to tell apart physically. The call is the only way to distinguish between the two, and even the calls are very similar! I've added a link for the gray treefrog... it mentions both pretty thoroughly.

http://en.wikipedia.org/wiki/Hyla_versic...