I've never heard of beetle death. Just Googled it and still have no clue. What kind of trees are dead? if there's a certain type of tree that is being killed in your area, you probably don't want to plant the same thing. I'd always start out by planting trees in the woods that are native to your area.

thanks I used my sister's non scientific explanation. I believe these are the ash borers that have arrived in the state. The trees show damage consistent with the explanation, but are too damaged to really identify. We would like to replant some of the woods with native trees and are looking for recommendations. So ashes are probably out as well as elms. We would like to maintain a wooded appearance to the property, there are already 2 acres which are grass and we will eventually covert these to gardens. Deer fencing first lol. So what native trees do you like that deer do not? lol

Congratulations on your new house. As far as I know, Emerald ash borer has not yet made it to Eastern Pennsylvania. Have you heard otherwise?

Trees die eventually, and the woods everywhere have dead trees, so you may just be seeing the cycle of life at work. See what other trees around are doing well, and plant more of them, perhaps: American beech, red maple, sugar maple, red oak, white oak, swamp oak, aesculus, redbud, hawthorne, musclewood... there are so many wonderful trees native to our area.