I have a very natural wooded lot with several dead trees. I would like to know if all of these trees need to be cut down. One is a dead arbutus that has grown out of the cliff over the water. It has been dead for many, many years. Is it a danger to either continue to leave it, or to cut it down? It is a beautiful tree and would prefer to leave it alone unless it is a danger. Other dead trees are scattered on my lot. I have read that dead trees are home to various birds and do not want to cut any tree down unnecessarily. Are all dead trees a greater danger of blowing down? Or do some have extensive root systems to keep them strong enough to leave alone?