Trees dying, dangers rising: Major tree mortality events rapidly increase forest fuels and snag hazards

Abstract

An extreme multi-year drought with extensive bark beetle outbreaks in California from 2012 to 2016 killed an estimated 147 million trees. This included ponderosa pine, incense cedar, white fir, and pinyon pine, rapidly changing forests over vast areas. Recently published work by Rocky Mountain Research Station (RMRS) researchers Sharon Hood and Charlotte Reed found that major tree mortality events like these increase surface and canopy fuels - dead needles, branches, and logs - which may result in more extreme forest fires and increased emissions when these areas burn. Drought often triggers bark beetle outbreaks in forests, where low moisture can stress trees and make it easier for beetles to kill them.

Citation

Bernhard, Adrienne; Hood, Sharon M.; Reed, Charlotte. 2024. Trees dying, dangers rising: Major tree mortality events rapidly increase forest fuels and snag hazards. Science You Can Use (in 5 Minutes), September 2024. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 2 p.