The Washington Post recently published an article on wildfires (“Was 2015 a record year for wildfires? Dispute fans a debate over U.S. forests“) that is a mixed bag of information. There are some great quotes from Chad Hanson and a few others that counter the industrial forestry perspective that we can and need to log our way out of large fires. However, the idea that most historic fires were small and did not burn up and kill trees may not be accurate.
There are two things going on.
One is the climate today is different than it was much of the last century so comparisons may not be accurate, and there is the problem of conflating different tree species that have very different burning histories.
The perspective, in particular, that dry forests were dominated by low severity high frequency fires that did not kill trees is based on a climate that is different than prevailed for much of the last century which was cooler and wetter than today. When you compare the historic role of fire, even in the drier forests, with fires that were burning under similar major drought conditions back through the centuries, you find similar occurrence of mixed to high severity fires burning–even in the dry forest ecosystems. Also where species like ponderosa pine are at higher elevations mixing with other species as in the Colorado Front Range, you find ponderosa pine burning in mixed to high severity more than in lower, drier areas.
Thomas Swetnam is correct when he says that figures from the earlier part of the last century did include fires in the Eastern US that are no longer occurring or considered in the numbers. However, there are other indications that large fires were still common under certain climate conditions. And Swetnam certainly appreciates the role of climate in fires.
However, the total acreage figure also has a lack of precision in another way. It fails to make distinction of fire by ecosystem type. Most of the acreage burning across the West and in Alaska are in the higher, moister forests of lodgepole pine, spruce, fir, and other species–these forests have always burned in large mixed to high severity blazes. And since the natural fire rotation in these forests is so long, fuels naturally accumulate. So to use these acreages and these fires to terrorize the public to suggest “fuel build up” has occurred as an excuse to support a logging program is disingenuous. The Forest Service should acknowledge that most of the acreage burning are forests that have historically always burned at high severity.
One of the assumptions behind current Forest Service policy is that logging will reduce large fires. Yet the review articles that have looked at this issue have all concluded that under “severe” fire weather/climate, thinning/logging does not preclude large fires. So the starting assumption of most of the current FS work is not well supported by science. And of course, we have many examples of clearcut forests–areas with very limited fuels– that burn quite regularly when the weather conditions are right.
Even in the days long before there was “fire suppression” you had large blazes that often killed trees. Keep in mind the 1910 Burn that raced across 3-3.5 million acres of Idaho and Montana occurred long before anyone could blame fire suppression. similar other large fires are recorded either in the geological record (sediment traces in geological studies, pollen and charcoal studies) as well as in other ways like looking at early government records of expeditions, General Land Office, etc.
Furthermore, these large blazes are not a disaster as pointed out. The forest has evolved with large fires over evolutionary time. Even in the pine forests, there were occasional large blazes, and the forest ecosystem rolls with the punches. Many species depend on these large fires.
One can’t know what was really said by someone in a news report–reporters do get quotes wrong–but I would agree with the Chris Topik, TNC representative, that more people are living in the forest and thus vulnerable to fire. But I disagree with his implied solution that we need more logging of the forest, rather it rests with the county governments to limit home building in these areas, and to reduce the flammability of homes not the forest. We simply cannot log our way to a fire-proof forest.
