Squirrel Intimidation

I walked out on the back deck this morning and this is what I found.

This is the  tip of a branch from a black locust tree. They are sharp as a needle and there are none near our house. The only explanation is that the squirrels are sending me a message to back off my terrorizing them and chasing them across the yard. That is okay, because they do not know who they are messing with!