USA — Report authors Elizabeth D. Reinhardt, Robert E. Keane, David E. Calkin and Jack D. Cohen delve into objectives for treating wildland fuel, explaining in detail the reasoning they have used in addressing the need for forest fuel management.
Wildlands cannot be fire-proofed, the report states. Given the right conditions, wildlands will inevitably burn. It is a misconception to think that treating fuels can fire-proof important areas.
The authors claim that fire ignition in forests is rarely affected by fuel treatment, and especially in the west there are often occurences of dry lightning.
Unless vegetation is eliminated from a site, even areas with intensive fuel treatments have residual biomass, the report states, which in turn can become dry and capable of burning easily in the right conditions. The authors note that in many cases those in charge of forest management understand this principle of forest biomass, but there may be some unrealistic community expectations about fuel management.
The authors then proceed to make their argument that the focus of fuel treatment programs should be on creating less devastating fire events and not on supplementing fire suppression efforts.
Citing what is described as the wildland fire paradox, the authors state that successful fire suppression results in fewer acres burned, leading to more fuel accumulation, thus managing fuels to aid in suppression can lead to a greater build up of fuels in the areas outside of the treatment zone. This, they claim, will lead to more intense fires in the event of unsuccessful suppression.
Citing Colorados 2002 Hayman fire and also the 2007 Angora fire near Lake Tahoe, the authors point out examples of fuel breaks and other suppression-oriented fuel treatments that were simply jumped by the massive fires, creating more burned area and more massive fires.
Even the most intensive fuel treatment may be rendered ineffective by the dynamics of large wildfire behavior, so designing treatments to minimize adverse fire effects may be a more effective strategy than designing treatments that attempt to exclude fires, the authors state.
In the Angora fire, the authors state, there were unburned trees in between the fire zone and the Wildland Urban Interface (WUI), suggesting that the homes themselves and the vegetation nearest to them were more ignition prone than the trees in the WUI.
Addressing this occurence, the authors state, There are opportunities for reducing the home ignition potential during extreme WUI fires without the necessity of changing the broader-scale wildfire behavior. That is, effective WUI fuel treatments for preventing WUI fire disasters can focus on the structures and their immediate surroundings.
The authors note that while the varying ownerships of WUI lands can obstruct agencies from mitigating WUI ignition potential directly, the opportunity exists to explicitly define for the WUI fire potential (i.e. the home ignition zone) consistent with areas of jurisdiction and separately from ecological wildfire issues.
Under the heading Even extensive fuel treatments may not reduce the amount of area burned over the long-term and furthermore, reduction of area burned may actually be an undesirable outcome, the authors reiterate their argument that reducing fire size can result in larger, more extreme fires in later years, stating that the majority of acreage burned by wildfire in the U.S. occurs in a very few wildfires under extreme conditions.
Much of the discussion in this section focuses on the relevance of the long-term picture in forest management, noting that large fires were common to western forests before European settlement and many plant species in these forests have adapted to survive those fires.
The authors also state, The perception that all large fires leave vast areas in severely burned wastelands is also false; the burn pattern of large fires is generally very complex with many areas moderately to lightly burned. They go on to state that large fires could possibly be used as a means to reintroduce fire to ecosystems in which it had once played a part but has been excluded for years.
Warning against evaluating the success of fuel treatment programs in terms of burned area, the authors claim that the strategy will nearly always fail over long-time periods.
Again returning to the idea of fuel management aiming to increase a forests ability to withstand adverse effects of future fires, the authors state This can be done b[y] ensuring the modified fuelbed will support a fire that will create or maintain stands similar to those that occurred on the historical landscape.
Any fire lightning or human caused could offer a unique opportunity to restore fire to historically fire-dominated landscapes and thereby reduce fuels and subsequent effects.
Further coverage, including the conclusion of the report, will follow in upcoming editions of the Siskiyou Daily News. The first article in the series was published in the Friday, March 27 edition of the Daily News.