Research Database
Displaying 41 - 60 of 93
The effects of thinning and burning on understory vegetation in North America: A meta-analysis
Year: 2017
Management in fire-prone ecosystems relies widely upon application of prescribed fire and/or fire-surrogate (e.g., forest thinning) treatments to maintain biodiversity and ecosystem function. The literature suggests fire and mechanical treatments proved more variable in their effects on understory vegetation as compared to their effects on stand structure. The growing body of work comparing fire and thinning effects on understory vegetation offers an opportunity to increase the generality of conclusions through meta-analysis. We conducted a meta-analysis to determine if there were consistent…
Publication Type: Journal Article
Impacts of lodgepole pine dwarf mistletoe (Arceuthobium americanum) infestation on stand structure and fuel load in lodgepole pine dominated forests in central Colorado
Year: 2017
Parasitic plants are capable of causing substantial alterations to plant communities through impacts on individual host plants. Lodgepole pine dwarf mistletoe is an important parasite in forests of the western USA that causes reductions to productivity and is thought to alter wildland fuel complexes. These impacts are hypothesized to vary with infestation severity. To test this, we used a linear mixed modeling approach to evaluate the relationship between dwarf mistletoe infestation severity and parameters representing stand structure and surface and canopy fuels in infested lodgepole pine…
Publication Type: Journal Article
Burning the legacy? Influence of wildfire reburn on dead wood dynamics in a temperate conifer forest
Year: 2016
Dynamics of dead wood, a key component of forest structure, are not well described for mixed- severity fi re regimes with widely varying fi re intervals. A prominent form of such variation is when two stand- replacing fi res occur in rapid succession, commonly termed an early- seral “reburn.” These events are thought to strongly infl uence dead wood abundance in a regenerating forest, but this hypothesis has scarcely been tested. We measured dead wood following two overlapping wildfi res in coniferdominated forests of the Klamath Mountains, Oregon (USA), to assess whether reburning (15- yr…
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
Disturbance, tree mortality, and implications for contemporary regional forest change in the Pacific Northwest
Year: 2016
Tree mortality is an important demographic process and primary driver of forest dynamics, yet there are relatively few plot-based studies that explicitly quantify mortality and compare the relative contribution of endogenous and exogenous disturbances at regional scales. We used repeated observations on 289,390 trees in 3673 1 ha plots on U.S. Forest Service lands in Oregon and Washington to compare distributions of mortality rates among natural disturbances and vegetation zones from the mid-1990s to mid-2000s, a period characterized by drought, insect outbreaks, and large wildfires.…
Publication Type: Journal Article
Forest disturbance across the conterminous United States from 1985-2012: The emerging dominance of forest decline
Year: 2016
Evidence of shifting dominance among major forest disturbance agent classes regionally to globally has been emerging in the literature. For example, climate-related stress and secondary stressors on forests (e.g., insect and disease, fire) have dramatically increased since the turn of the century globally, while harvest rates in the western US and elsewhere have declined. For shifts to be quantified, accurate historical forest disturbance estimates are required as a baseline for examining current trends. We report annual disturbance rates (with uncertainties) in the aggregate and by major…
Publication Type: Journal Article
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
Fire severity and cumulative disturbance effects in the post-mountain pine beetle lodgepole pine forests of the Pole Creek Fire
Year: 2016
Recent large scale mountain pine beetle (Dendroctonus ponderosae Hopkins, MPB) outbreaks have created concern regarding increased fuel loadings and exacerbated fire behavior and have prompted a desire to understand the effects of sequential disturbances on the landscape. However, previous research has focused on quantifying fuel loadings and using operational fire behavior models, rather than direct field measurements, to understand changes in fire severity following MPB. The 2012 Pole Creek Fire in central Oregon partially occurred in gray stage (8–15 years post-MPB epidemic) lodgepole pine…
Publication Type: Journal Article
Changing disturbance regimes, ecological memory, and forest resilience
Year: 2016
Ecological memory is central to how ecosystems respond to disturbance and is maintained by two types of legacies – information and material. Species life-history traits represent an adaptive response to disturbance and are an information legacy; in contrast, the abiotic and biotic structures (such as seeds or nutrients) produced by single disturbance events are material legacies. Disturbance characteristics that support or maintain these legacies enhance ecological resilience and maintain a “safe operating space” for ecosystem recovery. However, legacies can be lost or diminished as…
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
Effects of Drought on Forests and Rangelands in the United States: A Comprehensive Science Synthesis
Year: 2016
This assessment provides input to the reauthorized National Integrated Drought Information System (NIDIS) and the National Climate Assessment (NCA), and it establishes the scientific foundation needed to manage for drought resilience and adaptation. Focal areas include drought characterization; drought impacts on forest processes and disturbances such as insect outbreaks and wildfire; and consequences for forest and rangeland values. Drought can be a severe natural disaster with substantial social and economic consequences. Drought becomes most obvious when large-scale changes are observed;…
Publication Type: Report
A bird’s-eye view: Land-use planning and assessments in Oregon and Washington
Year: 2015
Developing forest lands and agricultural lands for other uses has wide-ranging implications. Land development can affect production from forest and agricultural lands, wildlife habitat quality, the spread of invasive species, water quality, wildfire control, and infrastructure costs. In its attempts to mitigate these effects, Oregon implemented statewide land-use planning laws in the early 1970s. Washington established less prescriptive laws in the 1990s. Policymakers, land managers, and various interest groups want to know the effect these laws have had on land use. Scientists with the…
Publication Type: Report
Native and exotic plant species respond differently to wildfire and prescribed fire as revealed by meta-analysis
Year: 2015
Questions: Wildfire is a natural disturbance that shapes vegetation characteristics worldwide, while prescribed fire is increasingly used to modify vegetation composition and structure. Due to invasion of many ecosystems by exotic species, a concern of land managers is whether wildfire and prescribed fire alter plant communities in favour of exotics. We assessed the global literature describing community-level responses of native and exotic species groups to wildfire and prescribed fire and characterized the geographic and temporal scope of the data to inform research needs. Location:…
Publication Type: Journal Article
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
Interactions among spruce beetle disturbance, climate change and forest dynamics captured by a forest landscape model
Year: 2015
The risk of bark beetle outbreaks is widely predicted to increase because of a warming climate that accelerates temperature-driven beetle population growth and drought stress that impairs host tree defenses. However, few if any studies have explicitly evaluated climatically enhanced beetle population dynamics in relation to climate-driven changes in forest composition and structure that may alter forest suitability for beetle infestation. We synthesized current understanding of the interactions among climate, spruce beetles (Dendroctonus rufipennis) and forest dynamics to parameterize and…
Publication Type: Journal Article
Before Wildfire Strikes: A Handbook for Homeowners and Communities in Southwest Oregon
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
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
Forest disturbance accelerates thermophilization of understory plant communities
Year: 2015
1. Climate change is likely to shift plant communities towards species from warmer regions, a processtermed ‘thermophilization’. In forests, canopy disturbances such as fire may hasten this processby increasing temperature and moisture stress in the understory, yet little is known about the mechanismsthat might drive such shifts, or the consequences of these processes for plant diversity.2. We sampled understory vegetation across a gradient of disturbance severity from a large-scalenatural experiment created by the factorial combination of forest thinning and wildfire in California.Using…
Publication Type: Journal Article
Tree mortality from drought, insects, and their interactions in a changing climate
Year: 2015
Climate change is expected to drive increased tree mortality through drought, heat stress, and insect attacks, with manifold impacts on forest ecosystems. Yet, climate-induced tree mortality and biotic disturbance agents are largely absent from process-based ecosystem models. Using data sets from the western USA and associated studies, we present a framework for determining the relative contribution of drought stress, insect attack, and their interactions, which is critical for modeling mortality in future climates. We outline a simple approach that identifies the mechanisms associated with…
Publication Type: Journal Article