U.S. Climate Resilience Toolkit

Beetle-killed trees (reddish brown) near Granby, Colorado. Various types of bark beetles are native to western forests, and tree density plays a significant role in the insects’ spread. But climate change is eroding one of the natural checks on their numbers and allowing them to invade new areas. Mild fall and winter temperatures are failing to kill off larva and are enabling infestations and damage on a massive scale.