San Bernardino, CA, USA — Bark beetles are good for the forest?
That’s probably news to officials responsible for managing the San Bernardino National Forest. But that’s essentially what a new study says.
The outbreak of beetles that burrow under a tree’s bark, eventually killing it, might reduce wildfire risk by naturally thinning forests, according to the report released Tuesday by researchers from Colorado State University, the University of Colorado and the University of Idaho.
“We are suggesting that the supposed fire risk is probably overblown,” said Bill Romme, professor of fire ecology at Colorado State and the lead researcher. “It’s possible the insects are doing the forest thinning that we would never be able to afford.”
County Fire Marshal Peter Brierty said the study’s results might seem like a “nice, scientific theory” but it’s one that fails to account for the lives and property found in the wildland-urban interface zone – an area where people live in the wilderness.
“It is an absolutely serious, catastrophic threat when you have dead trees near the wildland-urban interface”and it’s completely unacceptable to fire officials, and I’m sure it’s unacceptable to the public.”
For the past several years, bark beetles have been blamed for killing millions of trees in the San Bernardino National Forest.
But, as Brierty pointed out, the 2003 Old Fire destroyed nearly 1,000 homes in the San Bernardino Mountains and its foothills. Much of the blaze was spurred by chaparral, the low-lying brush that burns extremely well and is not affected by bark beetles.
“In the long-term sense of the forest, eventually the bark beetle-killed trees will what? Fall to the ground, right?” Brierty said. “But it’s a time relationship. It’s not a good management practice to sit around and let it happen.”
The new study cautions that removing trees won’t stop the spread of the beetles. Dead or dying trees don’t mean the forest is unhealthy but “may instead reflect a natural process of forest renewal,” according to the study. Similar outbreaks have occurred in the past.
“Pine beetles killed millions of lodgepole pine trees over thousands of square miles in the Cascade and Rocky Mountains in the 1960s, 1970s and early 1980s,” according to the report.
Drought and denser forests because of decades of fire suppression have also contributed to the beetle outbreak, the reportsays.