The mortality rate is unprecedented and will fuel the state’s fire season.
Sequoia National Park. (Photo: USFS Region 5/Flickr)
The number of dead trees in California’s forests dramatically increased in just one year’s time.
For a state already in the throes of fire season, the discovery of a 65 percent increase in the number of dead trees within its forests is a troubling sign.
“These new numbers really show that the tree die-off is spreading at an astronomical rate,” said Amy Head, a Cal Fire education officer. “It’s unprecedented, and it’s changing the landscape of whole ecosystems in California.”
The new figures are based on a May aerial survey assessment that found millions of new dead trees across the state. The southern portion of the Sierras—from Tuolumne County down to Kern County—shows the most severe tree mortality rates per acre.
The issue is the persistent drought. Bark beetles have been having a field day on the state’s weakened trees. Typically the trees are strong enough to withstand the beetles’ attack, using sap, or “pitch,” to keep the tiny pests from infiltrating the wood, planting larvae, and cutting off the tree’s flow of nutrients from the leaves to the trunk. But with ever-increasing temperatures and less water, the stressed trees can’t put up a fight.
“Most species of bark beetles in California are native, they’ve been around here for a while, so that’s not a new threat,” Head said. “The issue now is there are a tremendous amount of trees already weakened when the beetles come in, and they can’t fend them off.”
But that’s just a drop in the bucket compared with what the Forest Service believes it needs to adequately protect the nation’s forest from devastating wildfires. Just last year, the agency spent more of its allocated budget on fighting wildfires than on all other services combined.
U.S. Agriculture Secretary Tom Vilsack estimates that by 2025, fighting wildfires will take up two-thirds of Forest Service funding—or nearly $1.8 billion—as summer temperatures continue to rise, and fire seasons continue to lengthen.
Vilsack sees the move in California to pay for fire suppression through emergency action as a way to change the way firefighting is funded. Instead of coming out of the Forest Service’s regular annual budget, wildfire fighting would be funded according to the severity of each season—similar to how Congress funds other natural disasters.
“While the fire risk is currently the most extreme in California because of the tree mortality, forests across the country are at risk of wildfire and urgently need restoration requiring a massive effort to remove this tinder and improve their health,” Vilsack said in statement. “Unfortunately, unless Congress acts now to address how we pay for firefighting, the Forest Service will not have the resources necessary to address the forest die-off and restore our forests.”