There is a rash of misunderstanding about forest ecosystems. Many agencies and timber companies are advocating logging/thinning to “restore” forest health. However, I know of no forest that evolved with chain saws. These timber advocates are exploiting the public’s natural fear of wildfire.
Logging/thinning only degrades forest ecosystems in multiple ways.
Logging sanitizes the forest by reducing dead snags and the creation of down logs which are critical to healthy functioning forest ecosystem. A healthy forest ecosystem functions and persist because of episodic death from beetles, drought, fire, and other sources of mortality. These natural processes leave behind “biological legacy” of dead wood. These biological legacies are critical to the resilience and future growth of the forest ecosystem.
Plus, logging enhances weed spread, soil compaction, sedimentation in our rivers, and changes age structure—all of which further harms our forest ecosystems.
Most of these “costs” are ignored by advocates of logging/thinning. But that is only the beginning of the litany of ecological impacts that logging/thinning creates.
Our forests are among our greatest carbon storage venues. Logging and production of forest products release the bulk of the carbon in our wood immediately — which is why logging is the most significant source of CO2 emissions in Oregon. Even after burning in a fire, most of the carbon remains on site as snags, roots, and charcoal.
Carbon storage after a fire gets to another factor. What burns in a forest fire are fine fuels like needles, grasses, cones, branches, and the like. That is why trees remain as snags after a blaze. And that is why logging larger trees doesn’t typically influence fire spread.
Large fires are infrequent. They only occur under specific climate/weather conditions. Ninety-eight to ninety-nine of all blazes are small — burning less than 5-10 acres. Nearly all of them self-extinguish without any fire suppression.
However, under extreme fire weather, which includes drought, high temperatures, low humidity, and wind, nothing can stop a blaze. Windborne embers are the primary vector for rapid fire spread.
Wildfire acreage burning is increasing — but that is a direct result of climate change. Hot, dry weather promotes wildfires. If fuels were the issue, the biggest fires would be in Oregon’s Coast Range where there is more biomass than just about any place in the nation. But fires are rare in the Coast Range because the climate/weather is cool and moist.
Many scientists, as well as even the Congressional Research Service has concluded that logging/thinning has little impact on fires when conditions are ripe for a large burn. Indeed, there is even evidence that logging/thinning by opening up the forest to sun and wind can increase fire spread by facilitating wind penetration and drying of forest fuels.
Furthermore, there is an abundance of evidence that the probability of a fire burning a “treated” area during a period when it might be useful is incredibly small—less than 1%.
While wildfires are inevitable and ecologically desirable, we don’t have to accept wildfires in our communities. We can fortify our communities against fire. We do this by reducing flammable materials working outward from the home. Evidence suggests that thinning or other fuel reductions more than a hundred feet from a building provides no additional security.