Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Mountain pine beetles have killed pine trees across vast areas of western North America since the late 1990s. Image of the northern Williams Range, Colorado, where beetles have killed more than 80 percent of mature lodgepole pine over many square kilometers.
