[Fwd: Fw: USGS News Release: USGS Research Indicates Fire Suppression and Fuel Buildup are Not Responsible for Chaparral Shrubland Fires in Southern California]

Patrick Foley patfoley at csus.edu
Sun Nov 2 18:42:21 EST 2003

-------- Original Message --------
Subject: Fw: USGS News Release: USGS Research Indicates Fire Suppression 
              and Fuel Buildup are Not Responsible for Chaparral 
Shrubland              Fires in Southern California
Date: Sun, 2 Nov 2003 04:55:48 -0500
From: Karen Claxon <kclaxon at earthlink.net>
Reply-To: Karen Claxon <kclaxon at earthlink.net>

----- Original Message -----
From: "Catherine E Puckett" <catherine_puckett at usgs.gov>
Sent: Friday, October 31, 2003 10:42 AM
Subject: USGS News Release: USGS Research Indicates Fire Suppression and
Fuel Buildup are Not Responsible for Chaparral Shrubland Fires in
Southern California

Catherine Puckett
USGS,  Western Region
Office of Communications
371 Redmond Rd.
Eureka, CA 95503
PHONE: 707-442-1329
FAX: 707-442-6021
EMAIL: catherine_puckett at usgs.gov

U.S. Geological Survey
U.S. Department of the Interior

News Release

Date:             Oct. 30, 2003
Contact:    Gloria Maender, 520-670-5596, gloria_maender at usgs.gov; Jon
Keeley, 559-565-3170, jon_keeley at usgs.gov

USGS Research Indicates Fire Suppression and Fuel Buildup are Not
Responsible for Chaparral Shrubland Fires in Southern California

With the loss of life and property being experienced in the fires
in four Southern California counties, research by the U.S. Geological
Survey on fire in the region reveals that to effectively manage fires to
help prevent loss of life and property in Southern California
it is essential to understand the natural role of fire in chaparral

Large, high-intensity fires sweep the chaparral landscape in this region
each year, threatening lives and homes, as is occurring with such
devastation in this area. Ecologists have long known that chaparral
ecosystems burn extensively and often, and that much of the dominant
vegetation in these systems is highly adapted to a fire-prone
Many native plants here have seeds that require fire to germinate, or
the kind of disturbed habitat fires leave behind to grow. It was long
thought that fire suppression played the same role in chaparral
as it has in forests, creating a build-up of fuels that can eventually
to more destructive fires.

"Past fire suppression is not to blame for causing large shrubland
wildfires, nor has it proven effective in halting them," said Dr. Jon
Keeley, a USGS fire researcher who studies both southern California
shrublands and Sierra Nevada forests. "Under Santa Ana conditions, fires
carry through all chaparral regardless of age class. Therefore,
burning programs over large areas to remove old stands and maintain
growth as bands of firebreaks resistant to ignition are futile at
these wildfires."

In recent studies Keeley and his colleague, C. J. Fotheringham of the
University of California, Los Angeles, analyzed historical records for
counties dominated by shrublands subject to periodic high-intensity
wildfires, from Monterey County in the north to San Diego County in the
south. They found that although fire suppression is critical to protect
homes, buildings and other structures, fire suppression does not prevent
large wildland fires in southern California shrublands because these
usually occur with powerful Santa Ana winds that blow at high speeds
the desert to the coast. In the present fire, hot Santa Ana winds of
60 mph greatly increased the intensity and the movement of the fire.
winds occur each autumn, at the time when natural fuels are driest.

A close analysis of state fire records reveals the real story, said
Since 1910, chaparral fires have become more frequent as the human
population has grown but fire size has not increased. The researchers
that large, intense fires were equally common in the years before
widespread fire suppression as today, and do not appear to be the result
fuels build-up. In this highly fire-prone ecosystem, suppression efforts
appear not to have greatly altered patterns of fire incidence. Keeley
that the greater financial cost of fires today is most likely the result
constant urban expansion into areas subject to frequent burning.

For example, written documents reveal that during the 19th century human
settlement of southern California altered the fire regime of coastal
California by increasing the fire frequency. This was an era of very
limited fire suppression, and yet like today, large crown fires covering
tens of thousands of acres were not uncommon. One of the largest fires
Los Angeles County (60,000 acres) occurred in 1878, and the largest fire
Orange County's history, in 1889, was over half a million acres.

The main ignition source of chaparral wildfires under natural conditions
lightning, but lightning-ignited fires are of an order of magnitude
in coastal ranges than in interior ranges of California and much of the
western United States, said Keeley. Keeley hypothesized that before the
arrival of humans, the majority of area burned occurred at overlaps of
summer and autumn weather events. Small lightning-ignited fires of
occasionally persisted until the arrival of autumn Santa Ana conditions.
Such fires then rapidly increased in size and might continue to burn
winter rains finally doused them.

Most fires in California shrublands are human-caused, and the beginnings
human influence on the natural fire regime date to pre-Columbian
who used fire to convert the dense shrubland to a more open mosaic of
shrubland and grassland, long before the arrival of Euro-Americans, said

Fotheringham and Keeley noted that that throughout much of the shrubland
landscape humans play a dominant role in promoting fires beyond what was
likely the natural fire cycle. Future fire management, they said, needs
take a strategic approach to prefire fuel manipulations and move beyond
evaluating effectiveness strictly in terms of area treated. Fire
should consider designing strategies tailored to different regions, as
there are marked differences between the central coastal region and
southern California in source of ignition, season of burning, and
historical patterns of population growth and burning.

In terms of management implications, the fire researchers note that:

7     The contemporary fire regime in these shrublands mirrors the
crown fire regime far more than is generally accepted and that
crown fires may be an inevitable feature of this landscape.
7     There may be little justification for using fire for resource
benefit, since vast portions of shrubland landscape currently experience
higher-than-normal fire frequency.
7     While landscapes managed by rotational prescription burning may
contribute to easier containment of fires burning under moderate weather
conditions, they are of limited value during severe weather such as the
Santa Ana winds causing such destruction to life and property now.
7     Limited and strategically placed prescription burns are the most
cost-effective way to help prevent large catastrophic wildfires in
California chaparral habitat.

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