Article / Book
View article.
Sagebrush ecosystems of western North America are experiencing widespread loss and degradation by invasive annual grasses. Positive feedbacks between fire and annual grasses are often invoked to explain the rapid pace of these changes, yet annual grasses also appear capable of achieving dominance among vegetation communities that have not burned for many decades. Using a dynamic, remotely sensed vegetation dataset in tandem with remotely sensed fire perimeter and burn severity datasets, we examine the role of fire in transitions to and persistence of annual grass dominance in the U.S. Great Basin over the past 3 decades. Although annual grasses and wildfire are so tightly associated that one is rarely mentioned without the other, our findings reveal surprisingly widespread transformation of sagebrush ecosystems by invasive annual grasses in the absence of fire. These findings are discussed in the context of strategic management; we argue a pivot from predominantly reactive management (e.g., aggressive fire suppression and post-fire restoration in heavily-infested areas) to more proactive management (e.g., enhancing resistance and managing propagule pressure in minimally-invaded areas) is urgently needed to halt the loss of Great Basin sagebrush ecosystems.
View article.
Native species that are abundant and persistent across disturbance-succession cycles can affect recovery and restoration of plant communities, especially in drylands. In the sagebrush-steppe deserts of North America, restoring deep-rooted perennial bunchgrasses (DRPBGs) is key to the strategy for breaking an increasingly problematic cycle of wildfire promoted by exotic annual grasses (EAGs) and displacement of perennials by post-fire increases in EAGs. We asked how Sandberg bluegrass (Poa secunda)—a common native grass that shares traits with EAGs such as resilience to disturbance and rapid, shallow-rooted, early season growth—(1) recovered after wildfire, (2) responded to different combinations of native-plant seedings of DRPBGs and EAG-targeting herbicides; and (3) in turn, related to DRPBG recovery.
View article.
This study used geospatial seed transfer zones as our focal management areas. We broadly considered generalized provisional seed transfer zones, created using climate and stratified by ecoregion, but also present results for empirical seed transfer zones, based on species‐specific research, as part of our case study. Historic fire occurrence was effective for prioritizing seed transfer zones: 23 of 132 provisional seed transfer zones burned every year, and, within each ecoregion, two provisional seed transfer zones comprised ≧50% of the total area burned across all years. Fire occurrence within PACs largely reflected the seed transfer zone priorities found for the ecoregion as a whole. Our results demonstrate that historic disturbance can be used to identify regions that encounter regular or large disturbance. This information can then be used to guide seed production, purchase, and storage, create more certainty for growers and managers, and ultimately increase restoration success.
View article.
Fuels, pre-fire weather, and topography were important predictors of burn severity, although predictor importance varied between fires. Post-fire debris-flow hazard rankings from predicted burn severity (pre-fire) were similar to hazard assessments based on observed burn severity (post-fire).
View article.
Biophysical and social data collected at the property level are used to investigate whether practitioner defined “communities” within a contiguous geographic area are distinct in dimensions relevant to tailoring wildfire preparedness and mitigation education efforts. Specifically, we ask: How can local, community-specific social data inform wildfire education efforts across diverse communities? To answer this question, the research attends to the notion that there is not a one-size-fits-all approach to fire adapted communities by investigating what (e.g., the messaging, the programs, the communication mode), if anything, about wildfire education efforts should be tailored to the local context?
View article.
Initial strategies were driven by resource objectives for only six of the 32 wildfires; firefighter hazard mitigation was the primary driver of all others. No fire exhibited every characteristic of the Tamarack Fire. Analog fires accounted for a small percent (3.4%) of large (> 121 ha) USFS lightning-caused ignitions. These fires were responsible for 61.6% of structures destroyed and 25.8% of total personnel commitments of large lightning-caused USFS fires.
View article.
We found that relative to their total forest area, California, New Mexico, and Arizona contained the greatest proportion of carbon highly vulnerable to wildfire-caused loss. We also observed widespread opportunities in the western US for using proactive forest management to reduce the risk of wildfire-caused carbon loss, with many areas containing opportunities for simultaneously mitigating the greatest risk from wildfire to carbon and human communities. Finally, we highlighted collaborative and equitable processes that provide pathways to achieving timely climate- and wildfire-mitigation goals at opportunity hot spots.
View article.
From 1992–2020, 50% of recreation-caused ignitions in these three states occurred on lands managed by the U.S. Forest Service. The mean annual number of recreation-caused ignitions on national forests in the three states during this period was relatively stable, about 500, whereas recreation-caused ignitions within other jurisdictions decreased by 40%. Improved understanding of the impact of human and climatic factors on recreation-caused ignitions could provide valuable insights for shaping policy and management decisions. We found that mean annual densities of recreation-caused ignitions on national forests were 7 times greater within 1 km of designated campgrounds than >1 km from campgrounds, although 80% of recreation-caused ignitions occured >1 km from designated campgrounds. Ignition density in campgrounds increased non-linearly with overnight visitor density; a doubling of visitor density was associated with a ∼40% increase in ignitions. Large (≥4 ha) recreation-caused wildfires, especially those ignited in designated campgrounds, tended to occur concurrent with drought and 1–2 years after anomalously wet conditions. These results suggest that accounting for drought in implementation of fire restrictions, and targeting wildfire-prevention awareness to recreational users outside designated campgrounds, might reduce the likelihood of recreation-caused ignitions.
View article.
We used the National Environmental Policy Act to identify four types of science information needed for making decisions relevant to public lands: (1) data on resources of concern, (2) scientific studies relevant to potential effects of proposed actions, (3) methods for quantifying potential effects of proposed actions, and (4) effective mitigation measures. We then used this framework to analyze 70 Environmental Assessments completed by the Bureau of Land Management in Colorado. Commonly proposed actions were oil and gas development, livestock grazing, land transactions, and recreation. Commonly analyzed resources included terrestrial wildlife, protected birds, vegetation, and soils. Focusing research efforts on the intersection of these resources and actions, and on developing and evaluating the effectiveness of mitigation measures to protect these resources, could strengthen the science foundation for public lands decision making.
View article.
The results project increases in the number of simultaneous 1000+ acre (4+ km2) fires in every part of the Western USA at multiple return periods. These increases are more pronounced at higher levels of simultaneity, especially in the Northern Rockies region, which shows dramatic increases in the recurrence of high return levels.