Event Website
http://www.nafew2009.org/
Start Date
6-23-2009 3:40 PM
End Date
6-23-2009 4:00 PM
Description
Recent large-scale, severe wildfires in the western United States have prompted extensive fuel treatment programs to reduce potential wildfire size and severity. Often, unmerchantable material is mechanically masticated because removing the material is cost-prohibitive. Mastication treatments involve shredding, chopping, or chipping small trees and/or shrubs into small chunks and leaving the material on site. While it is obvious that mechanical treatments will increase surface fuel loads, few studies have addressed how treatments alter fuel particle size and quantity. We examined how mastication treatments alter the distribution of woody material size by comparing paired masticated and untreated sites in lodgepole pine (Pinus contorta), ponderosa pine/Douglas-fir (Pinus ponderosa/Pseudotsuga menziesii), and 3) Pinyon pine (Pinus edulis) ecosystems 2-4 years after mechanical treatment. As expected, total woody fuel loadings increased in the treated areas of each ecosystem. However, the magnitude of the total increase differed among the ecosystems (lodgepole pine > ponderosa pine > pinyon-juniper). Average total woody fuel loads in the untreated areas ranged between 7 to 9 Mg/ha, but increased to 29 to 50 Mg/ha in treated areas. Large diameter fuels (>7.62 cm) represent about 33 to 65% of the total woody fuel load in the untreated areas, but only about 11% of the total fuel load in the treated areas. The majority of woody fuels in treated areas were <2.54 cm in diameter. Needle litter mass was similar among treatments, indicating that needles are still a component of the forest floor complex, but are mixed with other fuel types or buried. The increased surface woody fuel component in treated areas corresponds to a shift from a needle fuel bed to a compact woody/needle fuel bed. This change in the fuel bed composition and orientation will likely influence fire behavior and effects.
Included in
Surface Fuel Loadings in Mulching Treatments in Colorado Coniferous Forests
Recent large-scale, severe wildfires in the western United States have prompted extensive fuel treatment programs to reduce potential wildfire size and severity. Often, unmerchantable material is mechanically masticated because removing the material is cost-prohibitive. Mastication treatments involve shredding, chopping, or chipping small trees and/or shrubs into small chunks and leaving the material on site. While it is obvious that mechanical treatments will increase surface fuel loads, few studies have addressed how treatments alter fuel particle size and quantity. We examined how mastication treatments alter the distribution of woody material size by comparing paired masticated and untreated sites in lodgepole pine (Pinus contorta), ponderosa pine/Douglas-fir (Pinus ponderosa/Pseudotsuga menziesii), and 3) Pinyon pine (Pinus edulis) ecosystems 2-4 years after mechanical treatment. As expected, total woody fuel loadings increased in the treated areas of each ecosystem. However, the magnitude of the total increase differed among the ecosystems (lodgepole pine > ponderosa pine > pinyon-juniper). Average total woody fuel loads in the untreated areas ranged between 7 to 9 Mg/ha, but increased to 29 to 50 Mg/ha in treated areas. Large diameter fuels (>7.62 cm) represent about 33 to 65% of the total woody fuel load in the untreated areas, but only about 11% of the total fuel load in the treated areas. The majority of woody fuels in treated areas were <2.54 cm in diameter. Needle litter mass was similar among treatments, indicating that needles are still a component of the forest floor complex, but are mixed with other fuel types or buried. The increased surface woody fuel component in treated areas corresponds to a shift from a needle fuel bed to a compact woody/needle fuel bed. This change in the fuel bed composition and orientation will likely influence fire behavior and effects.
https://digitalcommons.usu.edu/nafecology/sessions/mastication/8