Answer: I can't recommend spraying pesticides without knowing exactly what the insect is. I suggest you take/send samples of the insect and the damage to your County Cooperative Extension office for diagnosis. They will be able to diagnose and recommend the best thing to do for your trees. They will likly be listed under Colorado State University in your phone book or under County offices. I couldn't find your city in my Extension guide. If you send another email to the Q&A site with your County, I can provide the contact address and phone.
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