I have a dead avocado tree (long sad story-overpruned) in my back yard. I was thinking that a tree house would be nice so the tree isn't a total loss but I dont know how kosher it is to build in a tree that's dead. The trunk is about 18 inches. It's plenty strong now but I don't know if its prone to rot or termites and such. I guess the question is - is this tree worth building in?