Trees, which provide a crucial protection against climate change, are also under stress from some of climate change’s effects.

A mountainside in the Bob Marshall Wilderness in Montana shows, in one photograph taken from the air, the two forces that are devastating forests in the West. The area at upper right was burned in a recent fire, and the living stand of forest at lower left is under attack by mountain pine beetles. The reddish trees are already dead. Both fires and beetle attacks have become more common in a warming climate.

Red trees died recently, and gray ones probably died several years ago. The warming climate of the West encourages the growth of beetles. It also causes mountain snowpack to melt earlier in most years, creating summertime water stress for trees that makes them more vulnerable to beetle attack.

Attacks on a Protective Canopy, NYT.