Logging and Wildfires: What Does Science Say?

"The removal of large, merchantable trees from forests does not reduce fire risk and may, in fact, increase such risk. Fire ecologists note that large trees are 'insurance for the future - they are critical to ecosystem resilience.' Targeting smaller trees and leaving both large trees and snags standing addresses the core of the fuels problem."
(Dept. of Agriculture and Dept. of Interior, Report to the President [September 2000]).

"We concluded that commercial timber sales do not meet the criteria for forest restoration."
(November 2001 Audit by the Department of Agriculture's Office of Inspector General).

"[T]he National Research Council found that logging and clearcutting can cause rapid regeneration of shrubs and trees that can create highly flammable fuel conditions within a few years of cutting. Without adequate treatment of small woody material, logging may exacerbate fire risk rather than lower it."
(Dept. of Agriculture and Dept. of Interior, Report to the President [September 2000]).

"Timber harvest, through its effects on forest structure, local microclimate, and fuels accumulation, has increased fire severity more than any other recent human activity."
(Sierra Nevada Ecosystem Project, 1996. Final Report to Congress).

"The Congressional Research Service (CRS) recently addressed the effect of logging on wildfires in an August 2000 report and found that the current wave of forest fires is not related to a decline in timber harvest on Federal lands. From a quantitative perspective, the CRS study indicates a very weak relationship between acres logged and the extent and severity of forest fires. To the contrary, in the most recent period (1980 through 1999) the data indicate that fewer acres burned in areas where logging activity was limited."
(Dept. of Agriculture and Dept. of Interior, Report to the President [September 2000]).

"Mechanically removing fuels (through commercial timber harvesting and other means) can also have adverse effects on wildlife habitat and water quality in many areas. Officials told GAO that, because of these effects, a large-scale expansion of commercial timber harvesting alone for removing materials would not be feasible. However, because the Forest Service relies on the timber program for funding many of its activities, including reducing fuels, it has often used this program to address the wildfire problem. The difficulty with such an approach, however, is that the lands with commercially valuable timber are often not those with the greatest wildfire hazards."
(Government Accounting Office: "Western National Forests: A Cohesive Strategy is Needed to Address Catastrophic Wildfire Threats" [GAO/RCED-99-65]).

"Most of the trees that need to be removed to reduce accumulated fuels are small in diameter and have little or no commercial value."
(Government Accounting Office: "Western National Forests: A Cohesive Strategy is Needed to Address Catastrophic Wildfire Threats" [GAO/RCED-99-65]).

"Logged areas generally showed a strong association with increased rate of spread and flame length, thereby suggesting that tree harvesting could affect the potential fire behavior within landscapes."
(Historical and Current Forest Landscapes in Eastern Oregon and Washington. Part II: Linking Vegetation Characteristics to Potential Fire Behavior and Related Smoke Production [PNW-GTR-355]).

"As a by-product of clearcutting, thinning, and other tree-removal activities, activity fuels create both short- and long-term fire hazards to ecosystems. The potential rate of spread and intensity of fires associated with recently cut logging residues is high, especially the first year or two as the material decays. High fire-behavior hazards associated with the residues can extend, however, for many years depending on the tree. Even though these hazards diminish, their influence on fire behavior can linger for up to 30 years in the dry forest ecosystems of eastern Washington and Oregon."
(Historical and Current Forest Landscapes in Eastern Oregon and Washington. Part II: Linking Vegetation Characteristics to Potential Fire Behavior and Related Smoke Production [PNW-GTR-355]).

"Fire severity has generally increased and fire frequency has generally decreased over the last 200 years. The primary causative factors behind fire regime changes are effective fire prevention and suppression strategies, selection and regeneration cutting, domestic livestock grazing, and the introduction of exotic plants."
(Integrated Scientific Assessment for Ecosystem Management in the Interior Columbia Basin).

"The high rate of human-caused fires has generally been associated with high recreational use in areas of higher road densities."
(An Assessment of Ecosystem Components in the Interior Columbia Basin and Portions of the Klamath and Great Basins--Volume II [PNW-GTR-405]).