One third of Sierra Nevada forest wiped out by drought and fires

The Sierra Nevada region of California covers nearly 27 million acres of forests that provide habitat for thousands of animal species and is home to dozens of species of conifers, including native redwoods (the world’s tallest trees), sequoias (the world’s widest trees), or Great Basin bristlecone pines (the world’s longest living trees).

Now, a team of scientists from the University of California, Berkeley, has found that, from 2011 to 2020, a combination of devastating wildfires, droughts, and drought-related bark beetle infestations killed a staggering 30 percent of forests in the Sierra Nevada mountain range between Lake Tahoe and Kern County.

“It’s kind of a wake-up call, even to those of us that are kind of steeped in this field,” said study lead author Zackary Steel, an expert in Wildfire and Forest Management at UC Berkeley. “We’re moving from knowing this is a problem to quantifying the problem.”

Besides the overall decline in total conifer forest in this area, half of the mature forest habitats and 85 percent of high-density mature forests were either completely wiped-out or became low-density forests. Moreover, areas protected as habitat for the California spotted owl – an endangered bird at the center of a decades-long battle between environmentalists and the timber industry – experienced worse declines in tree canopy that other, non-protected areas.

According to the researchers, these findings call for a rejection of traditional conservation methods which preserve forests as they are, and for a use of controlled fires – as those ignited for centuries by California’s indigenous populations – as a tool for landscape regeneration and removal of low-lying vegetation that could increase the intensity of wildfires.

“The ecological idea is not to take out trees just to take out trees,” said Felicia Marcus, a researcher in Climate Policy at Stanford University. “If you take out enough of the smaller trees that snow can get through and hit the ground but you leave enough trees that it stays shaded, we’ll be able to maybe slow the rate of loss of snowpack which is perhaps the number one threat to stability in California’s water system.” 

Fortunately, state and federal government agencies are currently starting to rethink old practices and invest in wildfire resilience and forest health, with over $1,000 million dedicated to safeguard these historical forests. However, according to J. Keith Gilless, the chair of the state board of forestry and fire protection, the task of reverting forests to what they used to be will need long-term planning and dedication.

“We need to be clear to the policymakers that this isn’t something you go into with a one-shot infusion of money and it’s solved. It’s something where you’ve committed to moving to a different kind of landscape level management, that lets us truly deal with the natural hazard of wildfires,” he concluded.

The study is published in the journal Ecological Applications.

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—

By Andrei Ionescu, Earth.com Staff Writer