What Is This?

About a month ago, I would walk into my back yard and pick up handfuls of fallen leaves [see photo]. These were not dried leaves like you see in the fall, but healthy green leaves that were full in size and green as could be. Was my tree diseased? Was this a strange growing season? Why do I have to pick up piles of leaves every day? It was getting annoying to say the least.

The day I took these photos, I figured out what was going on. I was sitting on my back porch reading a book. I heard a very faint sound of rain falling. Just a few sprinkles, but then I heard some squirrels running around in my big Silver Oak tree. So I stop reading and look at the squirrel, then I realized there was FIVE squirrels. They were baby squirrels and they were all heading into the big pile of leaves that had collected in the "Y" of the branches. Silly me, it was a squirrel nest. I had never seen one before. I assure you, I saw five of them little buggers run into there. I waited and waited for one to pop his head out to get a shot of it, but no such luck. The rain started coming down heavy at this point and I had to head back indoors. A few days later, the nest fell from the tree and the squirrels are gone.