Research Database
Displaying 1 - 20 of 22
Small-scale fire refugia increase soil bacterial and fungal richness and increase community cohesion nine years after fire
Year: 2025
Small-scale variation in wildfire behavior may cause large differences in belowground bacterial and fungal communities with consequences for belowground microbial diversity, community assembly, and function. Here we combine pre-fire, active-fire, and post-wildfire measurements in a mixed-conifer forest to identify how fine-scale wildfire behavior, unburned refugia, and aboveground forest structure are associated with belowground bacterial and fungal communities nine years after wildfire. We used fine-scale mapping of small (0.9–172.6 m2) refugia to sample soil-associated burned and…
Publication Type: Journal Article
Characterizing post-fire delayed tree mortality with remote sensing: sizing up the elephant in the room
Year: 2024
BackgroundDespite recent advances in understanding the drivers of tree-level delayed mortality, we lack a method for mapping delayed mortality at landscape and regional scales. Consequently, the extent, magnitude, and effects of delayed mortality on post-fire landscape patterns of burn severity are unknown. We introduce a remote sensing approach for mapping delayed mortality based on post-fire decline in the normalized burn ratio (NBR). NBR decline is defined as the change in NBR between the first post-fire measurement and the minimum NBR value up to 5 years post-fire for each pixel…
Publication Type: Journal Article
Fire refugia are robust across Western US forested ecoregions, 1986–2021
Year: 2023
In the Western US, area burned and fire size have increased due to the influences of climate change, long-term fire suppression leading to higher fuel loads, and increased ignitions. However, evidence is less conclusive about increases in fire severity within these growing wildfire extents. Fires burn unevenly across landscapes, leaving islands of unburned or less impacted areas, known as fire refugia. Fire refugia may enhance post-fire ecosystem function and biodiversity by providing refuge to species and functioning as seed sources after fires. In this study, we evaluated whether the…
Publication Type: Journal Article
Refuge-yeah or refuge-nah? Predicting locations of forest resistance and recruitment in a fiery world
Year: 2023
Climate warming, land use change, and altered fire regimes are driving ecological transformations that can have critical effects on Earth's biota. Fire refugia—locations that are burned less frequently or severely than their surroundings—may act as sites of relative stability during this period of rapid change by being resistant to fire and supporting post-fire recovery in adjacent areas. Because of their value to forest ecosystem persistence, there is an urgent need to anticipate where refugia are most likely to be found and where they align with environmental conditions that support post-…
Publication Type: Journal Article
Interactions Between Fire Refugia and Climate-Environment Conditions Determine Mesic Subalpine Forest Recovery After Large and Severe Wildfires
Year: 2022
Infrequent stand-replacing wildfires are characteristic of mesic and/or cool conifer forests in western North America, where forest recovery within high-severity burn patch interiors can be slow, yet successful over long temporal periods (decades to centuries). Increasing fire frequency and high-severity burn patch size, under a warming climate, however, may challenge post-fire forest recovery, promoting landscape-level shifts in forest structure, composition, and distribution of non-forest patches. Crucial to a delay and/or impediment to this shift, fire refugia (i.e., remnant seed sources)…
Publication Type: Journal Article
Where and why do conifer forests persist in refugia through multiple fire events?
Year: 2021
Changing wildfire regimes are causing rapid shifts in forests worldwide. In particular, forested landscapes that burn repeatedly in relatively quick succession may be at risk of conversion when pre-fire vegetation cannot recover between fires. Fire refugia (areas that burn less frequently or severely than the surrounding landscape) support post-fire ecosystem recovery and the persistence of vulnerable species in fire-prone landscapes. Observed and projected fire-induced forest losses highlight the need to understand where and why forests persist in refugia through multiple fires. This…
Publication Type: Journal Article
Disjunct and decoupled? The persistence of a fire-sensitive conifer soecies in a historically frequent-fire landscape
Year: 2020
Local and regional species extirpations may become more common as changing climate and disturbance regimesaccelerate species’ in situ range contractions. Identifying locations that function as both climate and disturbancerefugia is critical for biodiversity conservation. Here, we investigate the persistence of a disjunct, fire-sensitiveconifer population, yellow-cedar (Callitropsis nootkatensis), in the historically frequent-fire landscape of the BlueMountains in eastern Oregon, USA. We used tree rings to reconstruct multi-century fire histories, which werethen used to compare historical mean…
Publication Type: Journal Article
Contributions of fire refugia to resilient ponderosa pine and dry mixed-conifer forest landscapes
Year: 2019
Altered fire regimes can drive major and enduring compositional shifts or losses of forest ecosystems. In western North America, ponderosa pine and dry mixed‐conifer forest types appear increasingly vulnerable to uncharacteristically extensive, high‐severity wildfire. However, unburned or only lightly impacted forest stands that persist within burn mosaics—termed fire refugia—may serve as tree seed sources and promote landscape recovery. We sampled tree regeneration along gradients of fire refugia proximity and density at 686 sites within the perimeters of 12 large wildfires that occurred…
Publication Type: Journal Article
Influence of fire refugia spatial pattern on post-fire forest recovery in Oregon’s Blue Mountains
Year: 2019
Context Fire regimes in many dry forests of western North America are substantially different from historical conditions, and there is concern about the ability of these forests to recover following severe wildfire. Fire refugia, unburned or low-severity burned patches where trees survived fire, may serve as essential propagule sources that enable forest regeneration. Objectives To quantify the influence of fire refugia spatial pattern and other biophysical factors on the process of post-fire tree regeneration; in particular examining both the proximity and density of surrounding refugia to…
Publication Type: Journal Article
Fire Refugia: What Are They, and Why Do They Matter for Global Change?
Year: 2018
Fire refugia are landscape elements that remain unburned or minimally affected by fire, thereby supporting postfire ecosystem function, biodiversity, and resilience to disturbances. Although fire refugia have been studied across continents, scales, and affected taxa, they have not been characterized systematically over space and time, which is crucial for understanding their role in facilitating resilience in the context of global change. We identify four dichotomies that delineate an overarching conceptual framework of fire refugia: unburned versus lower severity, species-specific versus…
Publication Type: Journal Article
Spatiotemporal patterns of unburned areas within fire perimeters in the northwestern United States from 1984 to 2014
Year: 2018
A warming climate, fire exclusion, and land cover changes are altering the conditions that produced historical fire regimes and facilitating increased recent wildfire activity in the northwestern United States. Understanding the impacts of changing fire regimes on forest recruitment and succession, species distributions, carbon cycling, and ecosystem services is critical, but challenging across broad spatial scales. One important and understudied aspect of fire regimes is the unburned area within fire perimeters; these areas can function as fire refugia across the landscape during and after…
Publication Type: Journal Article
Administrative and Judicial Review of NEPA Decisions: Risk Factors and Risk Minimizing Strategies for the Forest Service
Year: 2016
Changes in land use and management practices throughout the past century–in addition to drought and other stressors exacerbated by climate change–have degraded the nation’s forests and led to overgrowth and accumulation of hazardous fuels (GAO 2015). Because of these fuels, some forests now see high-severity fires that threaten communities as well as important natural and cultural resources. Restoring desired vegetation conditions, which can often be accomplished through mechanical thinning or prescribed burning, are central objectives of restoration and fuel reduction projects carried out by…
Publication Type: Report
Oregon's State Wood Energy Team: A Grant Program Review
Year: 2016
Oregon's State Wood Energy Team (SWET) is a state-level network supported by the United States Forest Service and led by Oregon Department of Forestry. The purpose of the SWET is to bring together experts in biomass energy to support the successful development and implemen-tation of wood energy systems and businesses. One of the Oregon SWET’S activities is a small grant program for project feasibility, engineering, and construction activities. Six grants were awarded in 2013-2015, totaling $204,700. Oregon State Uni-versity conducted an assessment of this program at the SWET’s request in…
Publication Type: Report
Tracking Progress: The Monitoring Process Used in Collaborative Forest Landscape Restoration Projects in the Pacific Northwest
Year: 2015
Several trends have emerged in recent years that affect the management of the National Forest System, particularly in the western U.S. One is the recognition of landscapes departed from a natural range of variation, especially with implications for wildfire management. Another trend is the economic decline in many rural communities of the western U.S., particularly those based on natural resource activities such as timber production. Finally, there is increasing acceptance of collaborative approaches to forest management. Collaborative approaches endeavor to increase mutual learning among…
Publication Type: Report
Social and economic monitoring for the Lakeview Stewardship Collaborative Forest Landscape Restoration Project
Year: 2015
The Fremont-Winema National Forest and the Lakeview Stewardship Group were awarded funding under the Collaborative Forest Landscape Restoration (CFLR) Program in 2012 for the 662,289 acre Lakeview Stewardship Project. The CFLR Program, administered by the U.S. Forest Service, seeks to increase restoration activities to improve the ecological conditions of forested landscapes while contributing to the social and economic well-being of communities located around national forests.The outcomes from CFLR project activities are monitored both through a standardized reporting framework established…
Publication Type: Report
Community Experiences with Wildfires: Actions, Effectiveness, Impacts, and Trends
Year: 2015
Wildfire has become a growing threat for communities across the American West and a complex concern for agencies tasked with community protection. This task has grown more difficult due to the increasing inci-dence of large fires and the continued expansion of the wildland-urban interface (WUI), the area where human habitations and wildland fuels abut or in-termix. These trends have motivated both federal policies and community-level responses to protect communities, lives, and infrastructure....
Publication Type: Report
Drivers of Wildfire Suppression Costs: Literature Review and Annotated Bibliography
Year: 2015
Over the past century, wildland fire management has been core to the mission of federal land management agencies. In recent decades, however, federal spending on wildfire suppression has increased dramatically; suppression spending that on average accounted for less than 20 percent of the USFS’s discretionary funds prior to 2000 had grown to 43 percent of discretionary funds by 2008 (USDA 2009), and 51 percent in 2014 (USDA 2014). Rising suppression costs have created budgetary shortfalls and conflict as money “borrowed” from other budgets often cannot be paid back in full, and resources for…
Publication Type: Report
Stewarding Forests and Communities: Final Report of the Dry Forest Zone Project
Year: 2014
During the past two decades, land managers and community leaders in the West have adopted sustainable land management methods to make forests healthier, and to maintain profitable local businesses that are beneficial to their communities. However their efforts were often siloed and were not making a big enough impact to offset the vast threat of wildfire and the effects of climate change that are increasingly pressing the region. Nor were these singular efforts being presented to federal lawmakers or agencies that have the need and ability to implement policies to replicate these successes…
Publication Type: Report
Dry Forest Zone Maps
Year: 2014
The Dry Forest Zone (DFZ) is a five-year project to address common natural resource-based economic development challenges through increased networking and capacity building at a regional scale. Sustainable Northwest leads this project in partnership with Wallowa Resources in northeastern Oregon, the Watershed Research and Training Center in northern California, and the Ecosystem Workforce Program at the University of Oregon. The central components of the DFZ strategy are: 1) To build strong local nonprofit organizations and collaborative processes to achieve forest and economic resilience, 2…
Publication Type: Map
Community-Based Natural Resource Management in Oregon: A Profile of Organizational Capacity
Year: 2012
Community-based organizations (CBOs) in Oregon are fostering natural resource management and economic development, particularly in public lands communities where the capacity of federal agencies, businesses, and others has dwindled. They have also become integral in reducing social conflict over land management and seeking community economic wellbeing. CBOs include non-governmental organizations and collaborative groups. These groups have broad missions that are grounded in local needs and integrate a number of priorities, but tend to have smaller staff and budgets than other groups such as…
Publication Type: Report