It is pretty high up in the tree. I would say it has been there for a while. It makes me wonder who put it up there and why they nailed it to the tree. This is not the first time we have run across something like this.
On our way to Hill View Manor in 2011 we happened to pass a house that had dozens of baby dolls and other stuffed animals out in their yard, tied or nailed to trees. Spooky creepy. I tried googling it but got nothing. If you know the significance (if any) of nailing a toy to a tree, I would love to hear it! email@example.com