The ash tree killing bug has been a massive problem in Western New York over the past few years. These tiny bugs embed themselves in ash trees and kill them and the problem begins as they may fall on your house. With high winds and the dead trees come issues.

You have to treat the trees to get rid of the bugs, but if you don't they can become a bigger and bigger problem. According to WIVB:

The longer a homeowner waits to take action, the more expensive it can get to remove an ash tree, because the tree service's insurance carrier might balk at taking down trees in back yards that are too far gone.