Synthesis / Tech Report
Maximizing the effectiveness of fuel treatments at the landscape scale is a key research and management need given the inability to treat all areas at risk from wildfire, and there is a growing body of scientific literature assessing this need. We synthesized existing scientific literature on landscape-scale fuel treatment effectiveness in North American ecosystems through a systematic literature review. We identified 127 studies that addressed this topic using one of three approaches: simulation modeling, empirical analysis, or case studies. Of these 127 studies, most focused on forested landscapes of the western United States. Together, they generally provided evidence that fuel treatments reduced negative outcomes of wildfire and in some cases promoted beneficial wildfire outcomes, although these effects diminished over time following treatment and were influenced by factors such as weather conditions at the time of fire. The simulation studies showed that fuel treatment extent, size, placement, timing, and prescription influenced the degree of effectiveness.
We synthesize insights needed to better address the long-standing challenges of innovation across disciplines to (i) promote coordinated research efforts; (ii) embrace different ways of knowing and knowledge generation; (iii) promote exploration of fundamental science; (iv) capitalize on the “firehose” of data for societal benefit; and (v) integrate human and natural systems into models across multiple scales. Fire science is thus at a critical transitional moment. We need to shift from observation and modeled representations of varying components of climate, people, vegetation, and fire to more integrative and predictive approaches that support pathways toward mitigating and adapting to our increasingly flammable world, including the utilization of fire for human safety and benefit. Only through overcoming institutional silos and accessing knowledge across diverse communities can we effectively undertake research that improves outcomes in our more fiery future.
We carried out a systematic literature review involving both a global and a case study approach (Portugal) to investigate the configuration of the social dimensions of wildfires in academic literature. We advance two interlocking claims: (i) human dimensions of wildfires are often simplified into shallow indicators of anthropogenic activities lacking social and historical grounding, and (ii) fire knowledge of Indigenous peoples and/or other forest and fire users and professionals remains overlooked. These arguments were manifest from the global-scale review and were confirmed by the case study of Portugal. The individual perceptions, memories and cultural practices of forest and fire users and professionals and the historical co-developments of fires, people and forests have been missing from wildfire research. Including and highlighting those perspectives will both add to existing knowledge and inform policies related to fire management by making them socially meaningful.
Our findings suggest that all deserts exhibited vulnerability to increasing fire disturbance because relatively low soil seed densities may not provide enough propagules for revegetation. Therefore, seeding of these communities may be especially important. In the cold deserts, this susceptibility was further evidenced by the fact that aboveground community composition in fire-affected areas was significantly different from the nearby unburned community even 30 years after fire and burned communities were associated with non-native species. That said, native species did exist in seed banks of burned sites and some taxa, like Sporobolus sp., occurred in high densities. Therefore, caution may be needed when using herbicide treatments to control exotic species as there may be unintended consequences of decreasing desirable species. In contrast, our warm desert sites exhibited less change in terms of seed densities, species richness and aboveground community composition following fire. In the face of more frequent fires, the lack of shrub seeds in the seed bank of all deserts was notable and we found no evidence of greater seed densities or unique species assemblages associated with shrub microsites.
Recent literature reviews and syntheses provide valuable references for land management practitioners and stakeholders engaged in designing, evaluating, and implementing scientifically credible wildfire- and climate-adaptation strategies. These syntheses are supported by thousands of peer-reviewed articles that evaluated the benefits and constraints of restoring fire to fire-dependent forest landscapes. This working paper summarizes key insights from the review of studies, described in detail below, that documented unprecedented, human-caused fire exclusion and its impacts on fire-dependent forest landscapes in western North America.
Researchers carried out a systematic literature review involving both a global and a case study approach (Portugal) to investigate the configuration of the social dimensions of wildfires in academic literature. We advance two interlocking claims: (i) human dimensions of wildfires are often simplified into shallow indicators of anthropogenic activities lacking social and historical grounding, and (ii) fire knowledge of Indigenous peoples and/or other forest and fire users and professionals remains overlooked. These arguments were manifest from the global-scale review and were confirmed by the case study of Portugal. The individual perceptions, memories and cultural practices of forest and fire users and professionals and the historical co-developments of fires, people and forests have been missing from wildfire research. Including and highlighting those perspectives will both add to existing knowledge and inform policies related to fire management by making them socially meaningful.
This review and analysis of the relevant scientific literature on the subject suggest that fuel characteristics have a gradual diminishing effect on the rate of fire spread in forest and shrubland fuel types with increasing fire danger, with the effect not being observable under extreme fire danger conditions. Empirical-based fire spread models with multiplicative fuel functions generally do not capture this effect adequately. The implications of this outcome on fire spread modelling and fuels management are discussed.
This “Sagebrush Conservation Strategy—Challenges to Sagebrush Conservation,” is an overview and assessment of the challenges facing land managers and landowners in conserving sagebrush ecosystems. This strategy is intended to provide guidance so that the unparalleled collaborative efforts to conserve the iconic greater sage-grouse (Centrocercus urophasianus) by State and Federal agencies, Tribes, academia, nongovernmental organizations, and stakeholders can be expanded to the entire sagebrush biome to benefit the people and wildlife that depend on this ecosystem. This report is organized into 3 parts.
Part I. Importance of the Sagebrush Biome to People and Wildlife; Part II. Change Agents in the Sagebrush Biome—Extent, Impacts, and Effort to Address Them; and Part III. Current Conservation Paradigm and Other Conservation Needs for Sagebrush
In developing this report, a cross-functional group of stakeholders and subject matter experts (SMEs) from across the nation convened to identify 33 challenges within 13 key WUI issues and develop recommendations to address each challenge. In total, 112 recommendations are presented. These recommendations address challenges in firefighter health and safety, public health and safety, evacuations, forest and rangeland health and resiliency, climate change, community planning and resiliency, infrastructure and utilities, communication strategy and engagement operations, socioeconomic impacts, recovery, emerging technology, data use and modeling, and risk management in wildland fire. The recommendations should be pursued together, forming a system of strategies that require urgent, sustained and actionable implementations. These recommendations are not quick fixes, but solutions for the long term. Leadership on and commitment to the implementation of these recommendations results in a safer America.