What are the consequences of allowing more wildfires to burn in the western United States? A new study by the USDA Forest Service and Oregon State University suggests that over the long term, naturally-ignited fires managed for restoration purposes can improve forest health and resilience and resistance to high-severity wildfires. The study also pointed out that there are trade-offs associated with managed wildfires, including increased short-term smoke production and potential impacts to wildlife habitat.
The new study, “Wildfires managed for restoration enhance ecological resilience," models long-term changes in forest resilience and trade-offs resulting from managing selected wildfires for ecological benefit (restoration wildfire). The practice of using wildfire as a tool is well-established in the southwestern United States and this study uses a landscape simulation model to test its potential for use in central Oregon. Wildfires burning under the right weather conditions and in appropriate locations can break-up forest fuels and create landscapes that are more resistant to large, high-severity fires. A combination of tools, including the use of restoration wildfire, can help managers reduce the risk of future mega-fires in the western United States.
“We know restoration wildfire can contribute to forest restoration goals. We wanted to quantify how much they contribute to these goals, and to also look at some of the negative impacts - one of the most relevant being additional smoke production,” said Ana Barros, lead author with Oregon State University. “We quantify trade-offs so that managers will have a more complete set of information to use in their decisionmaking.”
The researchers modeled two fire management policies, one with and one without restoration fire, over a 50-year period on about 3 million acres of forest in the Cascade Mountains of central Oregon. Modeling showed that restoration wildfires were very effective at creating and maintaining a resilient forest structure in mixed-conifer forests. The study suggests that restoration wildfire can decrease the potential for high-severity fire and increase the amount of resilient forest structure and habitat for species that benefit from burned forest, like the black-backed woodpecker (Picoides arcticus). However, the model also showed that restoration fire led to increased smoke production and resulted in the loss of habitat for a number of fire-sensitive species.
“We were surprised to find there were relatively few ignitions per season in the forest we studied that could be potentially managed as restoration wildfires, based where the wildfire ignites and if the weather conditions were suitable,” said Alan Ager, co-author with the USDA Forest Service Rocky Mountain Research Station. “Even though opportunities may be limited in Oregon’s national forests, the study does highlight that over the long run, managing natural fires could result in significant benefits in terms of future forest resiliency, thus adding to the current portfolio of forest management options.”
Funding for this research was provided by the USDA Forest Service and the National Science Foundation.
Citation: Barros, A. M. G., A. A. Ager, M. A. Day, M. A. Krawchuk, and T. A. Spies. 2018. Wildfires managed for restoration enhance ecological resilience. Ecosphere 9(3):e02161.
The Rocky Mountain Research Station (RMRS) is one of seven units within the U.S. Forest Service Research and Development. RMRS maintains 14 field laboratories throughout a 12-state territory encompassing parts of the Great Basin, Southwest, Rocky Mountains, and the Great Plains. RMRS also administers and conducts research on 14 experimental forests, ranges and watersheds and maintains long-term research databases for these areas. While anchored in the geography of the West our research is global in scale. To find out more about the RMRS go to www.fs.fed.us/rmrs. You can also follow us on Twitter at www.twitter.com/usfs_rmrs.
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