Aspen are becoming thin
Is there a way to identify a disease or pest that is killing our aspen trees? Established trees have wilting leaves just on one branch at a time, then the branch dies. They are getting supplemental water with a sprinkler system, so I don’t think it’s a watering problem.
Custer County Colorado trees and shrubs
Thank you Kurt! Would it help to apply a fungicide in the spring? If so, what would you recommend?