I was looking for a “Scientist of the Week” to honor and ran across this JFSP report. I’d like to give a vote of appreciation to these authors, and to the folks at JFSP for funding a useful synthesis of the research.
What I think it interesting about this paper is that the authors used different forms of knowledge (empirical, simulation, and case studies) to look at the question. I also like that they separated out (1) direct wildfire effects, (2) impacts to suppression strategies and tactics, and (3) opportunities for BWU. Some studies only talk about (1) or, in some cases, it’s not clear what exactly they are talking about. Here’s one chart.
Here is an interesting section of that:
Our synthesis focused primarily on how fuel treatments performed in the event of large wildfires, rather than the effect of fuel treatments at keeping wildfires small. Treatments offer suppression opportunities and subsequently influence how many fires are being extinguished in fuel treatments. In the case studies, there were comments that the wildfires ignited outside the fuel treatments and therefore when fuel treatments were burned by wildfires, the wildfires were already large. If fuel treatments allow for effective wildfire management, including successful full suppression compared to untreated areas, our focus may have undervalued their suppression benefit.
Longevity of fuel treatments was mentioned in all three synthesis types. In most cases fuel treatments were short–lived from 1 year to 20 years; however, in most cases the longevity of fuels was focused on surface fuels. Future studies should focus on the longevity of treatment effects in each relevant fuel stratum to test the following hypotheses: 1) surface fuels have the shortest fuel treatment longevity; 2) crown fuels have the longest fuel treatment longevity; 3) ladder fuels longevity decreases when crown fuels are separated creating growing space for latter fuels to flourish. Studies that focus on fuel strata longevity can inform managers when is it necessary to conduct maintenance treatments and choose a method of treatment that extends treatment longevity.
A discussion of research gaps in empirically based studies is premature given the current state of knowledge. Empirical approaches to understanding landscape–level fuel treatment effectiveness are in their infancy. Indeed, the field is at a point where clear and precise terms and concepts are not broadly recognized. The fundamental issue is the varied and imprecise use of the term ‘landscape.’ Wildfire is a landscape–level process. Fuel treatment effectiveness should be evaluated by how it affects that process, functionally, from a landscape perspective. The terms landscape scale and landscape size have little generalizable meaning. Large wildfires and or large treatments may be called ‘landscape’, but our inference on treatment effectiveness will remain constrained to within–site (i.e., within treatment) effects if the sampling design and analysis are site–level and not also measuring effects outside the treatment footprint. Therefore, instead of identifying gaps in understanding, there should be 1) broad recognition of what is meant by landscape–level fuel treatment effectiveness and how the characteristics of fuel treatments affect wildfire activity outside of treatment boundaries, and 2) long–term commitment to designing and implementing research projects at the landscape level over large areas that can inform questions and test hypotheses about the type, size, density, and configuration of fuel treatments that best affect subsequent wildfire in desirable directions.
The authors say “Wildfire is a landscape-level process. Fuel treatment effectiveness should be evaluated by how it affects that process, functionally, from a landscape perspective.” It seems to me that effectiveness would be measured as “do these treatments make wildfires easier to manage, with management including protecting communities, water and other infrastructure, and protecting species and watersheds from excessively negative impacts.” And I don’t really care about defining “landscape scale” except for the idea that say if you are planning PODs, you obviously have to think at the appropriate scale. But perhaps we all have different definitions. That could certainly make researchers’ lives difficult if we are all operating from different definitions and thinking we mean the same thing.