Fuel Treatment Effectiveness During the 2013 Rim Fire,
Stanislaus National Forest, California
Carol M. Ewell, Ecologist, USDA Forest Service, Adaptive Management Services Enterprise Team, Sonora, CA; Shelly L.
Crook, Fire Planner, USDA Forest Service, Stanislaus National Forest, Sonora, CA; Becky L. Estes, Province Ecologist, USDA
Forest Service, Eldorado National Forest, Placerville, CA; Morris C. Johnson, Research Fire Ecologist, Pacific Northwest
Research Station, Seattle, WA; Neil G. Sugihara, Regional Fire Ecologist, USDA Forest Service, Pacific Southwest Region,
McClellan, CA; Brenda L. Wilmore, Fire Ecologist, USDA Forest Service, Rocky Mountain Region, Eagle, CO.
Abstract—The 2013 Rim Fire started on the Stanislaus National Forest (NF) in the Central Sierra Nevada
Mountain Range of California and burned on land managed by several federal and state agencies and private
land owners. The Rim Fire grew to a final size of 257,314 acres and became the largest documented fire in
the Sierra Nevada Range. Fuel treatment objectives in the preceding two decades for the National Forest
System land within the 2013 Rim fire included protection of the wildland urban interface and recreation sites,
managing for forest resilience, and reducing hazardous fuels. Fuel treatment activities either removed or
mechanically rearranged vegetation and fuels, used fire to consume fuels, or some treatments combined
both fuel removal/alteration and prescribed fire. About 36,000 acres of treatments, many with overlapping
treatment footprints, occurred on the Stanislaus NF between 1995 and 2013. Over half of the treatments
implemented by the Stanislaus NF within the Rim fire perimeter were impacted by the two-day period of rapid
growth (34 percent burned on Aug. 21-22, 2013), which burned under 97th percentile weather conditions.
Treatments are typically designed for 90th percentile weather conditions.
The purpose of the national fuel treatment effectiveness monitoring program is to help answer the following
questions: 1) Are fuel treatments affecting fire behavior by reducing the fire intensity and/or rate of spread;
2) Does wildfire management improve by enhanced firefighter safety and/or reduced potential fire damage;
and 3) What are the lessons learned that are important to help improve the hazardous fuels program? The
Rim Fire fuel treatment effectiveness assessment attempted to quickly answer these questions through field
visits, eyewitness accounts, and spatial analyses.
Within the Rim fire, over 200 treated areas were first identified using a combination of historical spatial data
describing treatments and the Forest Service Activity Tracking System (FACTS) database, and then field visits
were completed on a subset of sites. Additionally, the preliminary vegetation severity data was utilized as a
composite burn index from the Rapid Assessment of Vegetation Condition after Wildfire process based on the
immediate post-fire imagery. When possible, interviews were conducted with incident staff that witnessed
fire behavior and management actions in or near the treatments. Initial assessments found that treatments
exhibited variable success in altering fire behavior, and the treatments that burned outside the two large
progression days more clearly altered fire behavior. Additionally, treatments that implemented a combination of mechanical thinning with prescribed fire or were recently completed were most successful at altering
fire behavior and subsequent immediate post-fire severity. Some treatments aided firefighter safety, such as
where they were easily accessed, located near priority values at risk, or located where tactics were planned
for this incident. Some treatments reduced fire damage or severity compared to nearby untreated sites. Fires
the size of the Rim fire present challenges to assessing fuel treatment effectiveness, particularly when they
burn under conditions that are outside of the treatment design.
In: Keane, Robert E.; Jolly, Matt; Parsons, Russell; Riley, Karin. 2015. Proceedings
of the large wildland fires conference; May 19-23, 2014; Missoula, MT. Proc.
RMRS-P-73. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky
Mountain Research Station. 345 p.
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The content of this paper reflects the views of the authors, who are responsible for the
facts and accuracy of the information presented herein.
USDA Forest Service Proceedings RMRS-P-73. 2015.