American River Watershed Institute arwi.us
Fire Safety Project | Problem: Fire in California

Forest Fuel Loads

Before European settlement, vegetation in California was dominated by a succession of more, smaller, and less damaging wildfires. Now, even fires that are not necessarily larger are burning more intensely. They are more costly to control and create greater risk of losses to the resources, improvements, and people in wildland areas.

The Sierra Nevada region is especially vulnerable to fire, due to historic fire management policies combined with unprecedented population growth. For most of the twentieth century, the response to fires in the Sierra Nevada was immediate attack fire suppression. Deteriorating forest health, increasing fuel loads, and other factors have led to more intense, destructive wildfires.

Over the last 80 years vegetative fuels have increased in tonnage per acre, resulting in unnaturally high fuel loads. Most of the public does not realize this and believe what they see now is "natural." Wildfires in this unnatural fuel load condition are very intense and more difficult to suppress. Add homes and personal property to these areas, and fire suppression is even more difficult.

Today, a primary goal of fire protection in California is to safeguard the wide range of assets found across wildland areas. These assets include life and safety, structures, range, recreation, hydroelectric power, fire-flood watersheds, soil erosion, water storage, water supply, scenic, timber, air quality, historic buildings, non-game wildlife, game wildlife and infrastructure.

Without fire, our forests grow dense and dangerous . . .

  • Thick vegetation burns faster and hotter
  • "Ladder fuels" allow low flames to travel high into the trees into a "crown fire"
  • Flames "jump" to start "spot fires" even miles away!
"Changes in land use and fire suppression policies over the past 150+ years have resulted in increased fuel loads over much of the watershed. This results in fewer small, low-intensity fires and more large, high-intensity fires than previous to that time . . . .

"Fires have been suppressed in the Sierra Nevada for many years, leading to high fuel loads in rural areas. . . . Many more people are building homes in remote areas, making wildland fire protection difficult for homeowners. . . . The risk of wildland fires can be reduced by working with local fire safe councils. . . ."

Bear River Watershed Plan

Fire ecosystem management over the past century:

  • Suppressed fire
  • Managed toward dense, even age, fuel loaded stands

Unintended consequence = catastrophic fire, resulting in:

  • Erosion
  • Water quality impaired
  • Flow and timing impaired

(See historic photos of forest changes in the Sierra Nevada, 1909-1989, from the Fire Safe Council.)