woodpecker nest?

In the front yard there are two southern oak trees on either side of the driveway. A couple of days ago Mary and I were talking next to the tree on the right. I saw a woodpecker fly in and land on the side of the tree. The woodpecker climb up to a higher point in the tree. I had seen this woodpecker recently on the tree to the left of the driveway. I commented to Mary about the woodpecker flying up but he was too high to see.

Yesterday I happened to notice a whole in the tree on the left.

The hole was about the size of a clenched fist. I have circled the hole in yellow. I thought that perhaps the woodpecker had made it for a nest.

I took some pictures and when I looked closely at the pictures, it appeared as if the rim of the hole was burnt. Also there appeared what might be a burn mark inside the hole. Now I am wondering if this hole may have been made by a lightning strike. I am baffled by the hole as to what may have created it. What do you think? All suggestions and theories are gratefully appreciated. So this is my bird story for Seaside. Have a good evening. Lew