Question
Help!  I just recently discovered that a large section of branches in my Mountain Ash tree (which I believe to be roughly 25 years old) is dead.  Like all trees, there are numerous large branch sections that all spread out from the trunk base.  It is one of these sections that has completely died, from the absolutely top of the branches all the way down to the central trunk.  Is this normal for a tree or does it sound like it may be sick?  This is the only tree in our entire yard, so I'd hate to lose it.  The only other thing that seemed odd to me is that the tree kept its red berries all through the winter (maybe it always does this and I've just never noticed, I'm not really sure).  I live in Southeastern Wisconsin and we've had a particularly wet spring as well, in case that makes any difference.  I'd really appreciate any help you can offer.  I'm tempted to call a tree expert, but I don't know who to trust or even where to find one!  Thanks so much for your time!

Answer
Not really sure why one branch would die and the rest live--could be an insect called a borer. I would cut the dead branch and remove it from the area--that way any insect in the wood would not re infest the living tree. From your description I can not tell what the problem maybe. I would suggest you call the local office of the the Wisconsin State Forestry agency and ask one of their Foresters (Forest Health Protection specialist) to come take a look. This is a free service in most states. Their web link is.

http://dnr.wi.gov/forestry/fh/staff/index.htm