What all those dead trees mean for the Sierra Nevada

The U.S. Forest Service estimates that since 2010, more than 102 million drought-stressed and beetle-ravaged trees have died across 7.7 million acres of California forest. More than half of those died last year alone.  Exacerbated by anti-wildfire policies that produced a crowded forest more vulnerable to drought, the massive dieback is unprecedented in the recorded history of the Sierra. The beetle epidemic is transforming the 4,500-foot to 6,000-foot elevation band of the central and southern range for decades to come, if not permanently. The sheer scale of mortality means that outside of developed areas, it’s likely that most of the tree corpses will be left to topple over. It will takes centuries to replace the legions of majestic old pines that have succumbed — if that is even possible in a warmer future that promises to alter the forest in ways ecologists can only guess.