I am not sure what the exact tree species is (may be black ash) but they are starting to die. below are pics of the back that dies and drops off. Any thoughts on what this might be?
Yes - Emerald Ash Borer. Got lots of ash around here looking like that. They get to be dangerous ...... never know when one's gonna drop - just big limbs or the whole tree. They're causing power outages in our region.
Here is a detailed look at the tree. I notice that a number of trees are growing sprouted limbs 2'4' long. I did gut one down and looked at the tree internals. Looks like tree is still alive but this may be a delayed reaction.
I work in hydro power plants. Went by a large resrvoir that one of the units I work on feeds, and all the ash trees are cut to the ground and left there, cut to about 6-8ft lengths. Probably about 2 years ago. Seen it at another reservoir too.