"My husband has been cutting fire wood for 50 years. He ran into something lately that he has never seen before. It is more like a tree growing inside another tree. The inside tree even has bark on it. The first he noticed was the center fell out when he started blocking it. I'm including some pictures for you. Any ideas?"
In fact you are looking at a deteriorating log cut for firewood. Although the tree did suffer from ring shake, the bacterial infection and additional conditions of rot caused the center of the tree trunk to literally drop out.
