Research Database
Displaying 21 - 40 of 83
Historical patterns of fire severity and forest structure and composition in a landscape structured by frequent large fires: Pumice Plateau ecoregion, Oregon, USA
Year: 2019
Context Lack of quantitative observations of extent, frequency, and severity of large historical fires constrains awareness of departure of contemporary conditions from those that demonstrated resistance and resilience to frequent fire and recurring drought. Objectives Compare historical and contemporary fire and forest conditions for a dry forest landscape with few barriers to fire spread. Methods Quantify differences in (1) historical (1700–1918) and contemporary (1985–2015) fire extent, fire rotation, and stand-replacing fire and (2) historical (1914–1924) and contemporary (2012) forest…
Publication Type: Journal Article
What drives ponderosa pine regeneration following wildfire in the western United States?
Year: 2019
Ponderosa pine (Pinus ponderosa Lawson & C. Lawson) is a prominent tree species in forests of the western United States. Wildfire activity in ponderosa pine dominated or co-dominated forests has increased dramatically in recent decades, with these recent wildfires often burning in an uncharacteristic manner due to past land management activities and changing climate. The structure and function of vegetative communities that develop following recent wildfires are highly contingent on ponderosa pine regeneration, making it important that the factors influencing this regeneration be…
Publication Type: Journal Article
Predicting post-fire attack of red turpentine or western pine beetle on ponderosa pine and its impact on mortality probability in Pacific Northwest forests
Year: 2019
In ponderosa pine forests of western North America, wildfires are becoming more frequent and affecting larger areas, while prescribed fire is increasingly used to reduce fuels and mitigate potential wildfire severity. Both fire types leave trees that initially survive their burn injuries, but will eventually die. Predicting delayed tree mortality has received considerable research attention to aid in post-fire planning and management. The amount of crown scorched is recognized as the most useful variable for discriminating between trees that live or die, but models gain discrimination with…
Publication Type: Journal Article
Prescribed fire regimes subtly alter ponderosa pine forest plant community structure
Year: 2019
Prescribed fire is an active management tool used to address wildfire hazard and ecological concerns associated with fire exclusion and suppression over the past century. Despite widespread application in the United States, there is considerable inconsistency and lack of information regarding the extent to which specific outcomes are achieved and under what prescribed fire regimes, particularly in regard to ecological goals related to plant community structure. We quantify differences and patterns in plant functional group abundance, species richness and diversity, and other key forest…
Publication Type: Journal Article
Prescribed fire regimes subtly alter ponderosa pine forest plant community structure
Year: 2018
Prescribed fire is an active management tool used to address wildfire hazard and ecological concerns associated with fire exclusion and suppression over the past century. Despite widespread application in the United States, there is considerable inconsistency and lack of information regarding the extent to which specific outcomes are achieved and under what prescribed fire regimes, particularly in regard to ecological goals related to plant community structure. We quantify differences and patterns in plant functional group abundance, species richness and diversity, and other key forest…
Publication Type: Journal Article
Recovery of ectomycorrhizal fungus communities fifteen years after fuels reduction treatments in ponderosa pine forests of the Blue Mountains, Oregon
Year: 2018
Managers use restorative fire and thinning for ecological benefits and to convert fuel-heavy forests to fuel-lean landscapes that lessen the threat of stand-replacing wildfire. In this study, we evaluated the long-term impact of thinning and prescribed fire on soil biochemistry and the mycorrhizal fungi associated with ponderosa pine (Pinus ponderosa). Study sites were located in the Blue Mountains of northeastern Oregon where prescribed fire treatments implemented in 1998 and thinning treatments in 2000 included prescribed fire, mechanical thinning of forested areas, a combination of…
Publication Type: Journal Article
Fires following Bark Beetles: Factors Controlling Severity and Disturbance Interactions in Ponderosa Pine
Year: 2017
Previous studies have suggested that bark beetles and fires can be interacting disturbances, whereby bark beetle–caused tree mortality can alter the risk and severity of subsequent wildland fires. However, there remains considerable uncertainty around the type and magnitude of the interaction between fires following bark beetle attacks, especially in drier forest types such as those dominated by ponderosa pine (Pinus ponderosa Lawson & C. Lawson). We used a full factorial design across a range of factors thought to control bark beetle−fire interactions, including the temporal phase of the…
Publication Type: Journal Article
Historical Fire–Climate Relationships in Contrasting Interior Pacific Northwest Forest Types
Year: 2017
Describing the climate influences on historical wildland fire will aid managers in planning for future change. This study uses existing historical climate reconstructions and a new fire history from the southern Blue Mountains in eastern Oregon, USA, to: 1) characterize historical fire-climate relationships, and 2) determine if climatic influences on fire differed among dry sites dominated by ponderosa pine (Pinus ponderosa Dougl. ex Laws) and more productive sites with significant older fire intolerant grand fir (Abies grandis [Dougl.] Lindl.) structure.
Publication Type: Journal Article
Efficacy of resource objective wildfires for restoration of ponderosa pine (Pinus ponderosa) forests in northern Arizona
Year: 2017
Current conditions in dry forests of the western United State have given rise to policy mandates for accelerated ecological restoration on U.S. National Forest System and other public lands. In southwestern ponderosa pine (Pinus ponderosa Laws.) forests, mechanized tree thinning and prescribed fire are common restoration treatments but are not acceptable for all sites. Currently there is much interest in managing naturally ignited fires to accomplish restoration objectives but few studies have systematically examined the efficacy of such “resource objective” wildfires for restoring historical…
Publication Type: Journal Article
Long-Term Effects of Burn Season and Frequency on Ponderosa Pine Forest Fuels and Seedlings
Year: 2017
Prescribed fire is widely applied in western US forests to limit future fire severity by reducing tree density, fuels, and excessive seedlings. Repeated prescribed burning attempts to simulate historical fire regimes in frequent-fire forests, yet there is limited long-term information regarding optimal burn season and frequency. In addition, burns are operationally feasible only in the spring and late fall, largely outside the historical wildfire season. This study quantifies the effect of seasonal reburns on woody surface fuels, forest floor fuels, and understory tree regeneration abundance…
Publication Type: Journal Article
Adapting fuel treatments in a changing climate - Prescribed fire, mechanical treatments, wildfire, and restoration
Year: 2016
The Available Science Assessment Project (ASAP) leads, EcoAdapt and Oregon State University’s Institute for Natural Resources, hosted a workshop during the International Association of Wildland Fire’s 5th Fire Behavior and Fuels Conference, in cooperation with the Northwest Fire Science Consortium and the Northern Rockies Fire Science Network. The workshop had managers and scientists build on a systematic map of the literature and results of an earlier scientist workshop. Outcomes from the manager and scientist workshop reflect perspectives of 36 participants from 30 organizations, which…
Publication Type: Report
Restoring forest structure and process stabilizes forest carbon in wildfire-prone southwestern ponderosa pine forests
Year: 2016
Changing climate and a legacy of fire-exclusion have increased the probability of high-severity wildfire, leading to an increased risk of forest carbon loss in ponderosa pine forests in the southwestern USA. Efforts to reduce high-severity fire risk through forest thinning and prescribed burning require both the removal and emission of carbon from these forests, and any potential carbon benefits from treatment may depend on the occurrence of wildfire. We sought to determine how forest treatments alter the effects of stochastic wildfire events on the forest carbon balance. We modeled three…
Publication Type: Journal Article
Did the 2002 Hayman Fire, Colorado, USA, Burn with Uncharacteristic Severity?
Year: 2016
There is considerable interest in evaluating whether recent wildfires in dry conifer forests of western North America are burning with uncharacteristic severity—that is, with a severity outside the historical range of variability. In 2002, the Hayman Fire burned an unlogged 3400 ha dry conifer forest landscape in the Colorado Front Range, USA, that had been the subject of previous fire history and forest age structure research. We opportunistically leveraged pre-existing data from this research, in combination with post-fire aerial imagery, to provide insight into whether the Hayman Fire’s…
Publication Type: Journal Article
Evaluating Prescribed Fire Effectiveness Using Permanent Monitoring Plot Data: A Case Study
Year: 2016
Since Euro-American settlement, ponderosa pine forests throughout the western United States have shifted from high fire frequency and open canopy savanna forests to infrequent fire and dense, closed canopy forests. Managers at Zion National Park, USA, reintroduced fire to counteract these changes and decrease the potential for high-severity fires. We analyzed existing permanent monitoring plot data collected between 1995 and 2010 to assess achievement of management objectives related to prescribed fire in ponderosa pine forests. Following first entry fire, ponderosa pine (Pinus ponderosa C.…
Publication Type: Journal Article
The ICO Approach to Quantifying and Restoring Forest Spatial Pattern: Implementation Guide. Version 3.0
Year: 2016
This document is intended as a “How To” guide for managers and stakeholders wishing to implement the Individual, Clumps, and Openings (ICO) method for silvicultural prescriptions and/or monitoring. Since its release in 2013, ICO has undergone a lot of development and improvement. In the third version of the guide we have included these important advancements:-Reference data from 4 regions is now available to assist in developing targets for clump sizes.-We developed an Android app to make marking and implementation easier. See section VII (page 38) for link to download.-Innovative…
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
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
Recovering lost ground: Effects of soil burn intensity on nutrients and ectomycorrhiza communities of ponderosa pine seedlings
Year: 2016
Fuel accumulation and climate shifts are predicted to increase the frequency of high-severity fires in ponderosa pine (Pinus ponderosa) forests of central Oregon. The combustion of fuels containing large downed wood can result in intense soil heating, alteration of soil properties, and mortality of microbes. Previous studies show ectomycorrhizal fungi (EMF) improve ponderosa seedling establishment after fire but did not compare EMF communities at different levels of soil burn intensity in a field setting. For this study, soil burn intensity effects on nutrients and EMF communities were…
Publication Type: Journal Article
Fire-Adapted Communities: The Next Step in Wildfire Preparedness in Klamath County
Year: 2015
This is a manual that helps homeowners and neighborhoods prepare their areas and their homes for wildfire. A fire-adapted community is a community located in a fire-prone area that requires little assistance from firefighters during a wildfire. Residents of these communities accept responsibility for living in a high fire-hazard area. They possess the knowledge and skills to prepare their homes and property to survive wildfire; evacuate early, safely and effectively; and survive, if trapped by wildfire.
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