You can look at the damage yourself on Google. Go to Google maps, and search for Granby, CO. Switch to the satellite view, and zoom in a couple of times. Then scroll around the area and look at the forests around Granby, especially directly north and south of it. The rust color is the dead trees.
This is one of the hardest hit areas, but it isn't the only place, and it is spreading north. Just east of Granby is Rocky Mountain National Park (infected), lus there are ski areas all around the infected region.
I’ll do that. I live on the other side of the divide from Granby and don’t see anything alarming. Apart from that I question the idea that beetles killing forests is unnatural.
You do know that Granby is in a big broad valley which has always been more or less treeless don’t you?