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Know the West

Latest: California’s tree die-off is bigger than you thought

An additional 36 million trees have died since May.


As California’s historic drought entered its fifth year in early 2016, 66 million trees were declared dead, killed by bark beetles, disease and dehydration. Forest-management agencies plan to log over 6 million acres, citing increased wildfire risk. But many scientists say that hot, dry, windy weather, not dead trees, drives fire, and that dead trees provide vital wildlife habitat. The magnitude of the die-off has caused land managers to rethink forest-management strategies ("California plans to log its drought-killed trees,” HCN, 8/8/2016). 

In mid-November, a U.S. Forest Service aerial survey revealed that drought has killed an additional 36 million trees since May 2016, bringing the total to 102 million since 2010. Most have been in the central and southern Sierra Nevada, but increasing numbers are in Northern California. The state had a record-setting wildfire season this year, adding urgency to the debate over what to do about all the dead trees.