The only management option available to reduce the vulnerabilities of frequent-fire forests is to modify forest structure

The Regents of the University of California, Berkeley have received a $451,400 federal Cooperative Agreement award from the Bureau of Land Management under the Joint Fire Science Program (CFDA 15.232) to investigate long-term fuel reduction and forest management strategies in the northern Sierra Nevada region of California. Through this 4-year award, the researchers will study patterns of fuel accumulation, vegetation change, and potential fire behavior over time across four different forest treatment regimes, including prescribed fire, mechanical thinning, and combinations thereof. The goal is to develop information to guide the frequency of treatments needed to maintain effective fuel reduction and forest resilience to wildfire, drought, and climate change. The study will engage federal, state, and private land managers, conservation groups, and elected officials to communicate the research findings and support improved forest management practices across the western United States.

These forests can be treated to reduce their hazards by mechanical treatments (thinning), prescribed fire, or combinations of these treatments. One recent paper that summarized 56 studies addressing fuel treatment effectiveness from eight western US states found general agreement that thinning followed by prescribed fire had positive effects in terms of reducing fire severity, tree mortality, and crown scorch. In contrast, burning or thinning alone had either less of an effect or none at all, compared to untreated sites. Managers is the western US have implemented fuel treatments with research done simultaneously to study their ecological impacts. While a great deal of information exists on the immediate effects (10 years post treatment highlighting the need for longer term studies on this important topic. This proposal integrated 2 long-term fuel reduction projects at UCB blodgett forest to address these information shortcomings. We will investigate the patterns of fuel accumulation, vegetation change, and potential fire behavior over time and develop information to inform the frequency of treatments needed to maintain treatment effectiveness. Specifically, we will investigate what appears to be distinct pathways in surface fuel development among four different treatment regimes: multiple applications of prescribed fire, mechanical thinning, or mechanical thinning followed by fire, along with untreated controls. This will include examining the influence of forest overstory structure and composition on fuel development and the role different treatments have on these overstory characteristics over time. We will use robust, replicated studies on fuels treatments in the northern sierra nevada that were installed 10 years ago. This proposal includes some of the longest running studies in the western US on fuels reduction and should be of interest to managers and scientists across this region who are working to restore frequent-fire forests to be more resilience to wildfire, drought, and climate change. Audiences targeted to receive information from this study include private, state, and federal forest managers, conservation groups such as the sierra club and sierra legacy, members and staff of the california board of forestry that have come to blodgett on multiple occasions to see and discuss the projects encompassed in this proposal, and state and federal elected officials and their staff. Recently senior staff members from senator padillas office came to blodgett to tour the FFS study and then followed up with stephens and others to get more information. Previously staff from senator feinsteins office and congressman scott peters office have also discussed this project repeatedly. Results from this project will be shared via the california fire science consortium with webinars and 2-page summary documents. Multiple field trips will be created with UC cooperative extension forestry and fire advisers to extend this information to diverse groups.