Hello

Your evergreen tree appears to be a Blue Spruce (Picea pungens). Colorado blue spruce have many problems. They are susceptible to several diseases and are attacked by many insects.

I’m attaching an article by Bert Cregg of MSU which explains all the problems that these trees have and why they have them. https://www.canr.msu.edu/news/what_is_spruce_decline_and_what_should_you_do_about_it

To correctly identify the problem of your tree and help you provide proper treatment, submit a sample/photo to MSU Extension’s Plant and Pest Diagnostic Lab at: https://www.canr.msu.edu/pestid/

A certified arborist would be able to assess your tree. To find a certified arborist in your area, go to: https://www.treesaregood.org ,the website of the International Arboriculture Society to find an arborist in your area for you to consult.

Thank you for contacting Ask Extension.