Chaparral Wildfire:

The Changing Fire Environment in

Southern California

Mike Rohde

Battalion ChiefOrange County Fire Authority

U.S. Geological Survey 2006 Congressional

Briefing Series-

Wildfire / Landslides

Distribution of chaparral in California

7 key types:

CeanothusRed ShankChamiseManzanitaScrub OakMontaneMixed

From Keeley, J.E. and F.W. Davis. 2006..

Millions of Californian’s live near chaparral wildlands, creating one of the most fire prone environments on earth

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(Data: Keeley and Fotheringham)

Studies by the USGS and the CaliforniaDepartment of Forestry and Fire Protectionshow a direct correlation betweenpopulation growth and fire frequency

California has a growing wildland fire problem!

USGS studies have redefined the fire regime for Southern California and caused fire agencies torethink how we pre-treat fuels to protect structures.

2003: 26 lives, 4,676 structures 739,000 acres lost

R.Krause photo

More frequent fire has had negativeenvironmental consequences, and long-term beliefs about prescribed fire use in chaparral have been challenged.

Chaparral fire regimes are unlike western forest fires in timber types

Alien grassland, Escondido, CA

Native chaparral, Temecula, CA

Fuel type conversion caused by too frequent fire is replacing nativeforest, shrub, and desert ecosystems with non-native vegetation…

Contributing to a cycle of ever-greater fire frequency, destabilized watersheds, landscape change, and natural resource loss.

These changes need further understanding and new research, such as the proposed USGS Southern California Multi-Hazards

Demonstration Project

R.W. Halsey photo

The flood and debris flow sequence that follows Southern California watershed fires has been as lethal as the wildfires themselves.

16 people died in San BernardinoCounty, Christmas Day- 2003,during flooding from hills burned by the Grand Prix-Old Fires two months earlier.

Photos: California State University, Long Beach

What should the frequency and placement of prescribed fire be tobest achieve habitat and fire hazard reduction needs?

R.W. Halsey photo

How are fuels and fire behavior changing?

Orange County Register photo

California Fire Services must have access to, and be a partner of future USGS study, and use this research to guide utilization of limited fire service resources to meet changing fire threats

San Diego Union Tribune photo