For decades, the Forest Service's principal objective for managing fires has been suppression, even in remote areas. But does this strategy, while seemingly beneficial in the short term, have hidden costs? What if the Agency didn't suppress those fires - where would those fires have spread and what would the effects have been? Can we measure the effects of suppressing those fires?
Rocky Mountain Research Station (RMRS) scientists quantified many of the hidden consequences of fire suppression. They found that the growth of many fires would have been curtailed by burned areas from previous fires. This clearly demonstrates how fire can create barriers to future wildfires in the form of fuel breaks, lessening the risk of catastrophic wildfire and potentially making safe management of the next wildfire easier. Studies also illustrate another hidden consequence of suppression: many ignitions would not have occurred because they were located on areas where an earlier fire would have left little fuel remaining on the site.
Scientists used a novel combination of fire behavior modeling technology, GIS, and local expertise in order to find that fires dramatically alter the number of subsequent ignitions and fire spread. These findings, the methods of which are documented in a step-by-step guidebook for managers to conduct similar analyses elsewhere, have broad national applicability. In fact, these methods were used to conduct comprehensive cost-benefit analyses of different response strategies for three large wilderness landscapes in the northern Rocky Mountains and the Southwest.
This research on hidden costs is improving the prioritization and planning of fuels management activities. It allows managers to frame future decisions and cost-benefit analyses in the context of past experiences, track the cumulative effects of suppression, and communicate tradeoffs to the public. These findings improve the quality and consistency of fire and fuels management decisions and help managers devise safe and effective strategies capitalizing on the opportunities for wider use of fire. Lastly, this research highlights the importance of wilderness areas for understanding fire ecology within unmanaged versus more heavily managed landscapes.