Research and Publications
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Frequent-fire forests of the western United States have undergone remarkable changes in structure, composition, and function due to historical exclusion of naturally occurring fire. Mechanized tree thinning to reduce forest density and fuel loads tends to be expensive and cannot be effectively implemented across all lands, and there is increasing interest in managing naturally ignited wildfires for meeting forest restoration objectives. To investigate general effectiveness of resource objective (RO) wildfires for restoring frequent-fire and associated forests of the western United States, a review of the related peer-reviewed literature was conducted.
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The increasing complexity of wildland fire management highlights the importance of sound decision making. Numerous fire management decision support systems (FMDSS) are designed to enhance science and technology delivery or assist fire managers with decision-making tasks. However, few scientific efforts have explored the adoption and use of FMDSS by fire managers. This research couples existing decision support system research and in-depth interviews with US Forest Service fire managers to explore perspectives surrounding the Wildland Fire Decision Support System (WFDSS). Results indicate that fire managers appreciate many WFDSS components but view it primarily as a means to document fire management decisions. They describe on-the-ground actions that can be disconnected with decisions developed in WFDSS, which they attribute to the timeliness of WFDSS outputs, the complexity of the WFDSS design, and how it was introduced to managers. We conclude by discussing how FMDSS development could address concerns raised by managers.
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Indaziflam (Rejuvra®, Bayer) is a pre-emergent herbicide that can manage annual grass seed banks and provide long-term reductions with minimal harm to established perennial vegetation. Indaziflam provided significant, long-term reductions in cheatgrass cover and density in invaded sagebrush-grasslands in western Wyoming without negative effects on native vegetation species richness. Observations from the site after an unplanned wildfire suggest that treatment three years earlier may have prevented the fire from burning significant areas of two large aerial treatment plots, likely by reducing the amount and continuity of fine fuel. These results suggest that indaziflam may help managers mitigate the impacts of invasion and proactively protect intact shrublands from cheatgrass-altered fire regimes.
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Exotic grasses are a widespread set of invasive species that are notable for their ability to significantly alter key aspects of ecosystem function. Understanding the role and importance of these invaders in forested landscapes has been limited but is now rising, as grasses from Eurasia and Africa continue to spread through ecosystems of the Americas, Australia, and many Pacific islands, where they threaten biodiversity and alter various aspects of the fire regime. The ecological, social and economic impacts of the grass-fire cycle associated with species such as cheatgrass (Bromus tectorum) have been long recognized in aridlands such as the iconic sagebrush ecosystems of the western US. However, the damaging impacts of invasive grasses in forestlands have received considerably less attention. We review literature, conceptual models, model output, and empirical evidence that indicate grass invasion in forest ecosystems may be an important yet largely under-recognized phenomenon. In combination with climate change, wildfire, and overstory management, invasive grasses could create a “perfect storm” that threatens forest resilience. Invasive grasses can be successful in forested environments or develop strongholds within forested mosaics and could provide the literal seeds for rapid change and vegetation type conversion catalyzed by wildfire or changes in climate. Although invasive grass populations may now be on the edge of forests or consist of relatively rare populations with limited spatial extent, these species may disrupt stabilizing feedbacks and disturbance regimes if a grass-fire cycle takes hold, forcing large portions of forests into alternative nonforested states. In addition, forest management actions such as thinning, prescribed fire, and fuel reduction may actually exacerbate invasive grass populations and increase the potential for further invasion, as well as broader landscape level changes through increased fire spread and frequency. Lack of understanding regarding the ecological consequences and importance of managing invasive grasses as a fuel may lead to unintended consequences and outcomes as we enter an age of novel and rapid ecological changes. This paper focuses on the contributory factors, mechanisms, and interactions that may set the stage for unexpected forest change and loss, in an effort to raise awareness about the potential damaging impact of grass invasion in forested ecosystems.
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Sagebrush ecosystems in the northern Great Basin face threats from invasive annual grasses and expanding conifers. Land managers need to work at large spatial scales to address these two ecological threats, but have limited resources to do so. This guide provides a framework for land managers to efficiently identify, discuss and address landscape-level threats. It is not an
instruction manual.
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The toolkit is comprised of three elements:
- A roadmap for invasive grass management in the West, with new best management practices for the identification, protection, and expansion of “core” areas – regions with relatively low, or no, annual grass invasion;
- Case studies highlighting the application of these practices in Idaho and Wyoming; and
- A new geospatial data layer (which uses analytical tools to compile existing federal data) to help state and local managers assess invasive annual grasses within their jurisdictions, while also offering opportunities to identify new cross-boundary collaborative projects.
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Land managers face a mounting variety of challenges, including how to efficiently dispose of excessive woody residues on forest sites (especially in the Western United States), maintain and improve soil productivity, improve forest resilience to changes in climate (especially as it pertains to drought and fire), and increase the effectiveness of reforestation activities. The use of biochar, a charcoal that is not readily degraded and is made specifically for land application, may have a role in meeting these challenges. Moreover, biochar may provide nursery managers with opportunities to produce seedlings for reforestation and restoration in a more sustainable way, particularly by reducing irrigation inputs, as evidenced through several trials summarized here.
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Drylands encompass over 40% of terrestrial ecosystems and face significant anthropogenic degradation causing a loss of ecosystem integrity, services, and deterioration of social‐ecological systems. To combat this degradation, some dryland restoration efforts have focused on the use of biological soil crusts (biocrusts): complex communities of cyanobacteria, algae, lichens, bryophytes, and other organisms living in association with the top millimeters of soil. Biocrusts are common in many ecosystems and especially drylands. They perform a suite of ecosystem functions: stabilizing soil surfaces to prevent erosion, contributing carbon through photosynthesis, fixing nitrogen, and mediating the hydrological cycle in drylands. Biocrusts have emerged as a potential tool in restoration; developing methods to implement effective biocrust restoration has the potential to return many ecosystem functions and services. Although culture‐based approaches have allowed researchers to learn about the biology, physiology, and cultivation of biocrusts, transferring this knowledge to field implementation has been more challenging. A large amount of research has amassed to improve our understanding of biocrust restoration, leaving us at an opportune time to learn from one another and to join approaches for maximum efficacy.
As MTBS data have been used over the course of many years and for many disparate applications, users should be aware that the MTBS burned area and severity products have been actively reviewed and revised to benefit from more robust satellite image availability and to address any observed quality issues. In a sample of 123 remapped fires, we found no significant change in the burned area boundary products when compared to the original mapped fires; however, significant changes did exist in the distribution of unburned, low, and moderate burn severity pixels within the thematic product.
Efforts to conserve biodiversity increasingly focus on identifying climate- change refugia – areas relatively buffered from contem-porary climate change over time that enable species persistence. Identification of refugia typically includes modeling the distribu-tion of a species’ current habitat and then extrapolating that distribution given projected changes in temperature and precipita-tion, or by mapping topographic features that buffer species from regional climate extremes. However, the function of those hypothesized refugia must be validated (or challenged) with independent data not used in the initial identification of the refugia. Although doing so would facilitate the incorporation of climate- change refugia into conservation and management decision mak-ing, a synthesis of validation methods is currently lacking. We reviewed the literature and defined four methods to test refugia predictions. We propose that such bottom- up approaches can lead to improved protected- area designations and on- the- ground management actions to reduce influences from non- climate stressors within potential refugia.