Research and Publications
View article.
Significant and lasting soil carbon change in rangeland ecosystems requires ecological state change. Although within-ecological state, soil carbon dynamics can occur, they are driven primarily by short-term fluctuations in weather, specifically precipitation, and are insufficient to provide reliable estimates of change to support policy and management decisions. Changes in grazing management typically do not result in ecological state change, apart from the vegetation structural change associated with long-term overgrazing. Dominant vegetation attributes such as shrub-to-grass ratios, cool season versus warm season plant production, and annual versus perennial growth habit define ecological state and are detectable accurately and cost-effectively using existing remote-sensing technology. These vegetation attributes, along with stationary soil properties, allow for mapping at scales consistent with a variety of policy and management decisions and provide a logical basis for developing a credible sampling framework for verification. Furthermore, state-transition models of ecological state dynamics are designed to provide information that can be used to support inventories and management decisions for soil carbon and other ecosystem services.
View article.
Forest recovery was generally associated with cooler, mesic sites in proximity to forested refugia; shifts toward scrub and grassland types were most common in warmer, dryer locations distant from forested refugia. Under future climate scenarios, models project decreases in postfire forest recovery and increases in nonforest vegetation. However, forest to nonforest conversion was partially offset under a scenario of reduced burn severity and increased retention of forested refugia, highlighting important management opportunities. Burning trends in the southwestern United States suggest that postfire vegetation will occupy a growing landscape fraction, compelling renewed management focus on these areas and paradigm shifts that accommodate ecological change. I illustrate how management decisions around resisting, accepting, or directing change could be informed by an understanding of processes and patterns of postfire community variation and likely future trajectories.
View article.
We evaluated the responses of forest structure, regeneration, old-tree mortality, and tree growth to forest restoration for 21 years in a landscape-scale (2114 ha) experiment in a ponderosa pine-Gambel oak forest in northern Arizona, United States. Relative to the start of the experiment in 1996, tree density and basal area (BA) in the treated area were reduced by 56 and 38%, respectively, at the end of the study period compared to the untreated control. Conifer seedling densities generally declined and sprouting hardwoods increased following treatment. Mortality of old oak trees was significantly higher in the treated area compared to the control, likely due to fire-caused injury during the prescribed burning. Mean annual BA increment of individual trees was 93% higher in the treated area than in the control. Our study provides new information on ponderosa pine forest responses to restoration treatments at broad spatial scales and under realistic operational conditions. Results from this study can help inform landscape-scale restoration projects in dry, fire-dependent forests.
View article.
To evaluate forest restoration and fuel treatment benefits and costs, we conducted a meta-analysis of benefit-cost ratios for restoration benefit types documented in the literature for Western U.S. dry mixed conifer forests at risk of uncharacteristic wildfires. A total of 120 observations were collated from 16 studies conducted over the last two decades, with benefits ranging from enhanced ecosystem services to extensively avoided wildfire costs. Significant variation in the value of restoration and fuel treatment benefit types was found, indicating that restoration benefits differ in value based on societal importance. Overall, 17 individual benefit types were aggregated to show that in the most valuable and at-risk watersheds, every dollar invested in forest restoration can provide up to seven dollars of return in the form of benefits and provide a return-on-investment of 600%.
View article.
Scaling up climate-adaptation in wildfire-prone watersheds requires innovative partnerships and funding. Water utilities are one stakeholder group that could play a role in these efforts. The overarching purpose of this study was to understand water utility engagement in wildfire mitigation efforts in the western United States. We conducted an online survey of water utilities in nine states and received 173 useable responses. While most (68%) respondents were concerned or very concerned about future wildfire events and the impact of wildfire on their operations, only 39% perceived their organization as responsible for mitigating wildfire risk. Federal land ownership decreased feeling responsible for wildfire mitigation, while concern for and information on wildfire increased feeling responsible for mitigation. The perception of response efficacy of mitigation actions for the 68 water utilities engaged in wildfire risk mitigation activities was very high, with most agreeing that mitigation actions are effective. Self-efficacy to implement mitigation actions, however, was mixed, with most utilities wanting more information on wildfire risk and impacts to watershed services. The most reported wildfire mitigation actions were forest thinning and stream restoration. Water utilities engaging in these actions typically partnered with government agencies or other water utilities to complete the work and funded these activities through water user fees and grants. Our findings suggest that water utility engagement in wildfire mitigation for water security could be increased through providing more assessments of wildfire risk to water utilities and through more outreach and engagement with water utilities operating on federal lands.
View article.
Changes to US wildfire policy in 2009 blurred the distinction between fires managed for resource benefits and fires with primarily suppression objectives, making management strategies difficult to track. Here, qualitative text is coded from a sample of 282 Wildland Fire Decision Support System Relative Risk Assessments completed on wildfires between 2010 and 2017 to examine the prevalence of different strategies and their associations with risk. Suppression is used most, associated with high risk. Managers discuss intent to suppress even when it is untenable. Monitoring, confine, or point protection are used much less commonly and when risk is low. The Southwest region discusses a diversity of strategies, leveraging landscape barriers from past management to support them; the Northwest discusses suppression or monitoring and rarely links strategy selection to barriers. Based on associations between physical barriers to fire spread, risk, and strategy, creating more barriers may provide a path forward to better implement fire policy.
View article.
In this white paper, we assert that the current wildfire management approach has partially inverted the wildfire problem as one in which wildland fires encroach on communities when, in actuality, it is communities that have increasingly impinged on wildlands where fires might appropriately play an important ecological role. As a result, predominant strategies continue to apply shortsighted, risk-averse reactions emphasizing community protection at the expense of creating resilient landscapes and promoting safe and effective wildfire responses. In doing so, managers are inadvertently limiting agency ability to build fire-adapted communities and generate landscape vegetation and fire conditions that support more meaningful and useful change.
View article.
The article provides a consideration of our capacity to cope, care, and coexist in a fiery world from a social and structural point of view. It focuses on privilege as the root cause of a long and troublesome history within the wildfire profession of not valuing all generational knowledge equally, not treating all cultures with the same respect, not embracing diversity and inclusion, and not affording the same status to all disciplines and voices. The article argues that we can strengthen our collective capacity to coexist with wildfire by embracing local and indigenous fire stewardship practices, by enabling workforce diversity and inclusive leadership culture, and by providing sustainable working conditions for wildland firefighters. To do so requires individual and collective noticing of what is wrong, and everyday action steps towards equity.
View article.
We combined predicted susceptibility with burn probability to quantify the 10-year total risk of cheatgrass dominance. Finally, we identified portions of the landscape (1) at risk of fire-induced conversion to cheatgrass dominance, (2) consistently susceptible to cheatgrass dominance, or (3) consistently resistant to cheatgrass dominance. At the scale of the sagebrush biome, we found that abiotic susceptibility to cheatgrass dominance drives total risk, regardless of fire. At local scales (i.e., individual 30 m pixels), burning increased the probability of cheatgrass dominance by a median of 14 %. Threshold-based analyses indicate that 10–31 % of the sagebrush biome was at risk of fire-induced dominance, with 55 % exhibiting abiotic resistance and 5 % exhibiting abiotic susceptibility to dominance regardless of fire. Burn probability was higher in areas predicted to be susceptible to dominance, illustrating how cheatgrass invasion can cause ecosystem conversions that are then sustained by grass-fire cycles. Disentangling the influence of abiotic conditions and fire contributes to our understanding of the mechanisms driving invasion dynamics, and modeling the probability of dominance can help anticipate where ecological transformations are at risk of occurring. Our approach can facilitate the prioritization of management actions in the sagebrush biome and be used as a framework for modeling invasion risk in other disturbance-prone ecosystems.
View article.
Here, we compared the effects of mechanical seeding techniques on soil properties following two wildfires occurring in similar climates with contrasting soil textures (silty loam and gravelly loam soils). Using either a rangeland or minimum-till drill to create furrows or mix broadcasted seeds into soils, we quantified wind erosion risk for unburned sites, burned nonseeded sites, and seeded sites according to soil aggregate stability, horizontal sediment flux, surface microtopography, and soil compaction. Effects of mechanical seeding were small relative to those created by wildfire. For burned areas, differences in site stability were greatest between sites. Following wildfire, the largest decrease in site stability occurred in fine-textured soils, where horizontal sediment transport was increased by nearly five orders of magnitude relative to unburned areas. Despite these initial differences, site stability in fine-textured soils may have improved to a greater degree than stability at the coarse-textured site. Furthermore, we found minimal differences between drill types on site stability but, instead, observed that the largest differences in soil properties were created by furrow versus broadcast seeding. The different outcomes of rehabilitation on site stability found here, paired with the spatial extent to which wildfire affects landscapes, highlights the importance of postfire monitoring of site stability in more locations that vary by soil, plant, landscape, and climatic variables.