Study of wildfire trends in Northwestern California shows no increase in severity over time

March 1st, 2012 in Earth / Environment

Even though wildfires have increased in size over time, they haven't necessarily grown in severity nor had corresponding negative impacts to the ecosystem, according to a recently published study appearing in the journal Ecological Applications.

A team of scientists from the USDA Forest Service and the University of California, Davis, assessed the size, severity and frequency of wildfires on four national forests—Klamath, Mendocino, Shasta-Trinity and Six Rivers—of northwestern California from 1910 to 2008 and their effects on the ecosystem. Fire severity is measured by its impact on resources such as watersheds, wildlife habitat, soils, vegetation and forest products. "High" severity patches within fires are areas where greater than 95 percent of the forest canopy was killed.

The study's key findings include:

These findings suggest that fires burning under less than extreme fire weather and fuel moisture conditions could be used to attain ecological and management goals since they generally produce less than severe results. In other words, the fires that are easy to put out could actually be used to achieve management goals.

Researchers note that these findings may be unique to the Klamath Mountains where the study was conducted. The steep, rugged mountains in northwestern California present different environmental features compared to the Sierra Nevada where similar studies did show a trend of increasing proportion of high severity over time.

"As we can see from these findings, one size does not fit all when it comes to managing wildfires," says Carl Skinner, PSW geographer, who co-authored the study. "This study has some very important implications for and forest management policies. Our results support the idea that wildfires could be managed for ecological benefit in this bioregion."

More information: To read the full article, go to: treesearch.fs.fed.us/pubs/40143

Provided by USDA Forest Service

"Study of wildfire trends in Northwestern California shows no increase in severity over time." March 1st, 2012. http://phys.org/news/2012-03-wildfire-trends-northwestern-california-severity.html