It began as a joke. I wonder if we'll ever get a Christmas tree this year. Maybe we should just put lights on the birch trees. "Oh birch tree, oh birch tree, how lovely are your branches!" Son number one even drew a picture of what our birch trees would look like, all decked out in their Christmas finery. While the boys were out of the house yesterday, I found a string of white lights in the basement and I did it. I put lights on our birch trees. The oldest sons think it's hysterical. The…