Forest & Fuels Management
Treatments on National Forest urban intermix parcels have three objectives:
- Reduce the severity of wildfire behavior
- Improve defensible space protection to adjoining private lands
- Enhance forest ecosystem health
Fuels reduction and forest health treatments are conducted simultaneously. These treatments include forest thinning, brush thinning and clean up of existing dead trees and surface fuels. The treatments are designed to separate surface and ladder fuels from the forest canopy, as well as providing crown separation. When treatments are completed, the boles of larger trees are commonly left on the ground and made available to the public as firewood during regulated fuel wood cutting periods.
Slash (limbs, tops of trees, and existing forest debris) that results from fuels reduction projects is chipped and spread back over the area, chipped and removed, or piled and later burned on site. Whenever possible, the Forest Service chips slash, however in many cases chipping is impractical or not cost effective.
On most urban intermix parcels, the use of mechanized ground based equipment is prohibited, severely restricted, or cost prohibitive, making hand removal the only management option. Hand removal is the practice of using crews to hand carry or wheel barrel wood and slash, no vehicles or machinery is used off road. This method is used for most of the fuels reduction work occurring on National Forest urban intermix parcels. Hand removal generally does not cause soil disturbance, however when soil disturbance does occur or mechanized equipment is used, any areas of disturbed soils are mitigated through installation of appropriate Best Management Practices (BMPs). BMPs are protection and mitigation measures developed to protect water quality by preventing non-point source pollution. Nonpoint pollution is defined by the EPA as pollution that is caused by rainfall or snowmelt moving over and through the ground picking up natural and human-made pollutants, finally depositing them into lakes, rivers, wetlands, coastal waters and ground waters.
Maintenance of Fuels Reduction
Fuels reduction treatments must be maintained over time to remain effective. The Forest Service is currently conducting maintenance of fuels reduction treatments on urban lots on a rotation of every 10-15 years. On some parcels, however, other conditions may arise, such as pockets of insect mortality or storm damage that can require more frequent treatment to maintain effective defensible space, fuels conditions, and to eliminate hazards.
Fuels Reduction Treatments Work!
In June of 2007 the Angora Fire started from an unattended campfire southwest of South Lake Tahoe. It burned 3,072 acres of land comprised of National Forest System, state, county, and private ownership, including over 250 structures. Included in these lands were 122 Forest Service urban intermix parcels that had previously received fuels reduction treatments as described above.
Immediately after the fire, an assessment team reviewed the effectiveness of fuels reduction treatments that had previously occurred in the fire area. Treatments on urban lots had occurred between 1997 and 1998 and were 8 to 9 years old when the Angora Fire occurred. Of the 70 urban lots reviewed, 68 exhibited surface fire behavior. Only 2 parcels exhibited crown fire behavior, one which had never been treated and one that had received treatment in 1994 using different treatment methods.
For more information regarding this report visit: http://www.cnpssd.org/fire/angorafireusfsfullreport.pdf
The California and Nevada Tahoe Basin Fire Commission (Fire Commission) was formed shortly after the fire. The Fire Commission report made the following finding (Finding 20):
“Fuel reduction treatments implemented on National Forest urban intermix parcels within the Angora Fire reduced fire behavior from crown fire to surface fire as designed”
Within this Finding, the report states that the treatments (integrated resource management projects under the Urban Lot EA) “exhibited modified fire behavior, including reduced ember production, and reduced heat and smoke allowing firefighters to be more effective.” The finding goes on to state “treated parcels also served as fuel breaks, allowing firefighters to safely protect structures and slowing fire spread” and that “eyewitness accounts, firefighter interviews and post fire on-site inspections indicated a significant reduction in fire intensity when fire entered treated urban lots (flame lengths were less than 4 feet).”
The Fire Commission report also makes the following recommendation (Recommendation 51):
“ The Governors should support fuels treatment prescriptions that proved effective in the Angora Fire on USDA Forest Service urban intermix parcels and encourage their continued use. In addition, the Governors should request:
A. USDA Forest Service to consider more intensive treatments on steeper slopes where only pre-commercial thinning treatments are now occurring.
B. USDA Forest Service to continue implementing the current plan to have all 3200 urban intermix parcels treated by 2010.
C. USDA Forest Service to continue to implement the plan for maintenance of fuels treatments on urban intermix parcels, including utilization of stewardship agreements with local fire districts and stewardship permits for local land owners.”
For more information visit: http://www.cnpssd.org/fire/angorafireusfsfullreport.pdf
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