Recent Fire History

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Recent Fire History
California and Nevada
1970 - 2007
California, Nevada, Hawaii Fire Council Reno,
Nevada October 22, 2008 Marva Willey,
Intelligence Coordinator, USFS, Northern
California Geographic Area
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Fire history can be considered in many ways and
at many scales. To perform an actual fire
history analysis takes time and to look at fire
history for two states could take a long time.
So, well focus just on the numbers that get
reported each year through the various reporting
systems utilized by the fire suppression
agencies, and consider a couple reasons why those
numbers are changing.
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Are fires getting larger?
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National Forest Acreage Burned and Number of
Fires by Decade 1910-1969
USDA Forest Service, National Forests Fire Report
1969
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Data from National Interagency Coordination Center
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Data from Cheetah3 and NIFC
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Perimeters of Fires Over 500 Acres by Decade
California and Nevada
1980-1989
1990-1999
2000-2007
California 662 fires 2,877,118 Acres Nevada
109 fires 788,427 Acres
California 612 fires 3,195,291 Acres Nevada
178 fires 2,198,466 Acres
California 510 fires 4,536,942 Acres Nevada
381 fires 5,001,433 Acres
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• Why?
• There are a number of factors which contribute to
  large fires.
• They include
• a change in fuel conditions since suppression
  activities really began
• the wildland urban interface
• resource drawdown

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Fuels
Exclusion of fire has resulted in a change in the
composition, structure, and density of
vegetation. This can be observed in many ways,
but retake photography definitely shows how fuels
have changed over the relatively short period of
time weve been suppressing fires.
1884. Photo by JS Diller, USGS
1995. Photo by G.Gruell and R.Olson
Gold Run Creek, 3 miles SW of Susanville, CA
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The increase and change in fuels is an issue that
has been recognized for a long time.
1899 - Gifford Pinchot observed "Where such
forest lands have been protected from fire, as
they are very largely through the progress of
settlement, young trees have usually sprung up in
great numbers under or between the scattered
veterans which had survived the fires, and a
dense and vigorous young growth stands ready to
replace, by a heavy forest, the open park-like
condition which the fire had created and
maintained..."
This change in vegetative composition and
structure allows other conditions such as drought
to affect the fuels that are available for
burning, and contributing to the increase in fire
size.
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Wildland Urban Interface
The wildland urban interface holds a unique
challenge for firefighters. The mix of structure
and wildland, often combined with limited
accessibility results in the firefighter having
to triage the site, maintaining a high level of
understanding and awareness of this unique
environment.
Where once you deployed all your suppression
resources to do perimeter control, you now must
divide your resources to provide structure
protection and do perimeter control. Wildland
urban interface fires will most likely receive a
higher priority rating when decisions are being
made about where to deploy suppression resources
leaving those fires burning outside WUI less
resources, which in turn could allow those fires
to become larger.
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Resource Drawdown
Resource drawdown and competition for resources
can also result in fires increasing in size.
For example, in Northern California in 2008,
there were so many fires that prioritization of
the most threatening fires resulted in leaving
many other fires unstaffed for several days,
which then required use of strategies and tactics
that normally wouldnt have been used if
resources had been available early on.
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Northern California Fires June and July 2008
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Our recent past has shown a marked increase in
acres burned and there is no evidence to suggest
that this will change any time soon. And so, the
answer to the question is yes, some fires are
larger than they were in our recent past. Large
fires are not necessarily a bad thing. They have
been a natural part of our ecosystems from the
beginning of time. This has been shown by
numerous fire history studies. The issues we
face today with large fires are the severity or
intensity of the fires which can result in often
catastrophic damage, destroying natural resource
values as well as homes.
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There are a number of fire history studies
available and people who are willing to conduct
them. For more information on fire history or on
the reporting systems utilized by suppression
agencies, please dont hesitate to contact
me. Thank You.