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The Northwest Fire Science Consortium works to accelerate the awareness, understanding, and adoption of wildland fire science. We connect managers, practitioners, scientists, and local communities and collaboratives working on fire issues on forest and range lands in Washington and Oregon.

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JFSP Regions

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NWFSC is one of
fifteen regional exchanges
sponsored by the Joint Fire Science Program.

JFSP Funding Opportunity Announcement Open now through 4pm PST, May 16, 2019

View the FUNDING ANNOUNCEMENT HERE

 

 

Hot Topics


Influence of fire refugia spatial pattern on post-fire forest recovery in Oregon’s Blue Mountains

Authored by W.M. Downing; Published 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 characterize the landscape of refugial seed sources.

Methods

We surveyed regeneration at 135 sites in stand-replacement patches across a gradient of fire refugia density in eastern Oregon, USA. We characterized the influence of refugial seed source pattern and other environmental factors on the abundance of regenerating seedlings, and examined the relationship between post-fire climate and the temporal pattern of ponderosa pine seedling establishment.

Results

Tree seedlings were present in 83% of plots 12–17 years post-fire, and densities varied substantially (0–67800 stems ha−1, median = 1100). Variation in seedling abundance was driven by the spatial patterns of refugial seed sources. Despite widespread post-fire shrub cover, high-severity burned forests have not undergone a persistent type conversion to shrublands. Ponderosa pine seedling establishment peaked 5–11 years after fire and was not closely associated with post-fire climate.

Conclusions

Fire refugia and the seed sources they contain fostered tree regeneration in severely burned patches. Management practices that reduce refugia within post-fire landscapes may negatively influence essential forest recovery processes.


Wild bee diversity increases with local fire severity in a fire‐prone landscape

Authored by S.M. Galbraith; Published 2019

As wildfire activity increases in many regions of the world, it is imperative that we understand how key components of fire‐prone ecosystems respond to spatial variation in fire characteristics. Pollinators provide a foundation for ecological communities by assisting in the reproduction of native plants, yet our understanding of how pollinators such as wild bees respond to variation in fire severity is limited, particularly for forest ecosystems. Here, we took advantage of a natural experiment created by a large‐scale, mixed‐severity wildfire to provide the first assessment of how wild bee communities are shaped by fire severity in mixed‐conifer forest. We sampled bees in the Douglas Fire Complex, a 19,000‐ha fire in southern Oregon, USA, to evaluate how bee communities responded to local‐scale fire severity. We found that fire severity served a strong driver of bee diversity: 20 times more individuals and 11 times more species were captured in areas that experienced high fire severity relative to areas with the lowest fire severity. In addition, we found pronounced seasonality in the local bee community, with more individuals and more species captured during late summer, especially in severely burned regions of the landscape. Two critical habitat components for maintaining bee populations—flowering plants and boring insect exit holes used by cavity‐nesting bees—also increased with fire severity. Although we detected shifts in the relative abundance of several bee and plant genera along the fire severity gradient, the two most abundant bee genera (Bombus and Halictus) responded positively to high fire severity despite differences in their typical foraging ranges. Our study demonstrates that within a large wildfire mosaic, severely burned forest contained the most diverse wild bee communities. This finding has particularly important implications for biodiversity in fire‐prone areas given the expected expansion of wildfires in the coming decades.


Fine scale assessment of cross boundary wildfire events in the Western US

Authored by P. Palaiologou; Published 2019

We report a fine scale assessment of cross-boundary wildfire events for the western US. We used simulation modeling to quantify the extent of fire exchange among major federal, state, and private land tenures and mapped locations where fire ignitions can potentially affect populated places. We examined how parcel size effects the wildfire transmission and partitioned the relative amounts of transmitted fire between human and natural ignitions. We estimated that almost 90 % of the total predicted wildfire activity as measured by area burned originates from four land tenures (Forest Service, Bureau of Land Management, private and State lands) and 63 % of the total amount results from natural versus human ignitions. On average, one third of the area burned by predicted wildfires was non-local, meaning that the source ignition was on a different land tenure. Land tenures with smaller parcels tended to receive more incoming fire on a proportional basis, while the largest fires were generated from ignitions in national parks, national forests, public and tribal lands. Among the 11 western States, the amount and pattern of cross-boundary fire varied substantially in terms of which land tenures were mostly exposed, by whom and to what fire sizes. We also found spatial variability in terms of community exposure among States, and more than half of the predicted structure exposure was caused by ignitions on private lands or within the wildland-urban interface areas. This study addressed gaps in existing wildfire risk assessments, that do not explicitly consider cross-boundary fire transmission and do not identify the sources of fire. The results can be used by State, Federal, and local fire planning organizations to help improve risk mitigation programs.


Social fragmentation and wildfire management: Exploring the scale of adaptive action

Authored by T.B. Paveglio; Published 2019

The research presented in this article responds to the deficit described above by exploring the ways that interaction between residents, land managers, fire professionals, and government officials’ influences local approaches to wildfire management. We use the term social dynamics in reference to the patterns, influences and perspectives characterizing the interaction between human actors surrounding wildfire management, including their influence on the scale at which management can occur. We conducted focus groups with a variety of professionals, residents, and government officials in a landscape spanning Idaho and Washington states of the U.S. Pacific Northwest to gain on-the-ground understandings of the ways that local social dynamics influence management strategies for wildfire. This includes exploring the extent to which variation in residents’ values, skills, perspectives and relationships with the landscape leads to support or enactment of wildfire mitigation efforts. Results of our effort help illuminate tangible opportunities and barriers to collective wildfire management across landscapes and explore how social dynamics might influence progress toward creating fire resilient landscapes. In a broader sense, our efforts provide insight on the creation of “fire adapted communities” across diverse human populations and the ways site-specific social dynamics might influence their variable occurrence.


Spatial and temporal assessment of responder exposure to snag hazards in post-fire environments

Authored by C.J. Dunn; Published 2019

Researchers and managers increasingly recognize enterprise risk management as critical to addressing contemporary fire management challenges. Quantitative wildfire risk assessments contribute by parsing and mapping potentially contradictory positive and negative fire effects. However, these assessments disregard risks to fire responders because they only address social and ecological resources and assets. In this study, we begin to overcome this deficiency by using a novel modeling approach that integrates remote sensing, field inventories, imputation-based vegetation modeling, and empirical models to quantify post-fire snag hazard in space and time. Snag hazard increased significantly immediately post-fire, with severe or extreme hazard conditions accounting for 47%, 83%, and 91% of areas burned at low, moderate and high-severity fire, respectively. Patch-size of severe or extreme hazard positively correlated with fire size, exceeding >20,000 ha (60% of our largest fire) 10-years post-fire when reburn becomes more likely. After 10 years, snag hazard declined rapidly as snags fell or fragmented, but severe or extreme hazard persisted for 20, 30 and 35 years in portions of the low, moderate and high-severity fire areas. Because forests are denser and wildfires burn with greater severity than historically, these hazardous conditions may represent novel management challenges where risk of injury or death to responders outweighs the benefits of directly engaging the fire. Mapping snag hazard with our methodology could improve situational awareness for both decision makers and fire responders as they mitigate risk during fire management. However, as more landscapes burn we anticipate increased responder exposure to extremely hazardous conditions, which may further entrench the wildfire paradox as fire managers weigh current response decisions with future challenges. Aligning land management objectives with wildfire management needs, in part by mapping responder exposure to snags and other hazards, could help overcome the wildfire paradox and produce desirable long-term outcomes. This research also demonstrates the importance of interdisciplinary collaboration to account for risk to all aspects of fire prone social-ecological systems as we learn to live with fire in rapidly changing environments.


NWFSC Research Brief #19 - Adjusting the lenses of past, present and future to bring into focus the role of frequent fire in dry forests

Authored by N.Fire Scien Consortium; Published 2019

In this study, the authors characterized historical fire return intervals, seasonality, and relationships with local and regional factors for 13 sites representative of southwestern Oregon dry forests on ridges and midslopes in the Rogue Basin of the Klamath Ecoregion. They used dendrochronology (cross-dated fire-scars from trees) to develop fire histories. Then using a systematic literature review, the authors were able to link local fire histories to a regional dataset and evaluate the data relative to more intensively studied conifer/hardwood forest types in California.


Growing up: Findings from a JFSP student project on post-fire conifer regeneration trajectories in eastern Oregon

Webinar Event from Northwest Fire Science Consortium

What will you learn?

This presentation will focus on findings from JFSP-supported graduate research on post-fire conifer establishment following recent wildfires in eastern Oregon's Blue Mountains. Given shifting climate and wildfire regimes, managers and researchers seek information on forest resilience and recovery trajectories. Understanding establishment and growth rates post-fire is pertinent both to fuels management planning, in cases of overabundant regeneration, as well as to decisions surrounding replanting for sites with limited post-fire regeneration. The presentation will summarize current knowledge on the relative influence of site-level versus climatic factors affecting regeneration in western North America, and present data from the Blue Mountains ecoregion.

Presenter:

Angela Boag, Research Associate, University of Colorado Boulder

Session Details: Wednesday May1st at 1:00 pm US/Pacific || Duration: 1.0 hour

Who should participate?

Managers/Practitioners, Scientists/Researchers, Other

Register HERE!

Prepare your computer or mobile device in advance: WebEx instructions

 


Historical patterns of fire severity and forest structure and composition in a landscape structured by frequent large fires: Pumice Plateau ecoregion, Oregon, USA

Authored by R.K. Hagmann; Published 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 structure and composition. Data include 85,750-ha tree-ring reconstruction of fire frequency and extent; > 375,000-ha timber inventory following > 78,900-ha fires in 1918; and remotely-sensed maps of contemporary fire effects and forest conditions.

Results

Historically, fires > 20,000 ha occurred every 9.5 years; fire rotation was 14.9 years; seven fires > 40,469 ha occurred during extreme drought (PDSI < − 4.0); and stand-replacing fire occurred primarily in lodgepole (Pinus contorta var. murrayana). In contemporary fires, only 5% of the ecoregion burned in 30 years, and stand-replacing fire occurred primarily in ponderosa (Pinus ponderosa) and mixed-conifer. Historically, density of conifers > 15 cm dbh exceeded 120 trees/ha on < 5% of the area compared to 95% currently.

Conclusions

Frequent, large, low-severity fires historically maintained open-canopy ponderosa and mixed-conifer forests in which large fire- and drought-tolerant trees were prevalent. Stand-replacing patches in ponderosa and mixed-conifer were rare, even in fires > 40,469 ha (minimum size of contemporary “megafires”) during extreme drought. In this frequent-fire landscape, mixed-severity fire historically influenced lodgepole and adjacent forests. Lack of large, frequent, low-severity fires degrades contemporary forest ecosystems.


Near-future forest vulnerability to drought and fire varies across the western United States

Authored by P.C. Buotte; Published 2019

Recent prolonged droughts and catastrophic wildfires in the western United States have raised concerns about the potential for forest mortality to impact forest structure, forest ecosystem services, and the economic vitality of communities in the coming decades. We used the Community Land Model (CLM) to determine forest vulnerability to mortality from drought and fire by the year 2049. We modified CLM to represent 13 major forest types in the western United States and ran simulations at a 4‐km grid resolution, driven with climate projections from two general circulation models under one emissions scenario (RCP 8.5). We developed metrics of vulnerability to short‐term extreme and prolonged drought based on annual allocation to stem growth and net primary productivity. We calculated fire vulnerability based on changes in simulated future area burned relative to historical area burned. Simulated historical drought vulnerability was medium to high in areas with observations of recent drought‐related mortality. Comparisons of observed and simulated historical area burned indicate simulated future fire vulnerability could be underestimated by 3% in the Sierra Nevada and overestimated by 3% in the Rocky Mountains. Projections show that water‐limited forests in the Rocky Mountains, Southwest, and Great Basin regions will be the most vulnerable to future drought‐related mortality, and vulnerability to future fire will be highest in the Sierra Nevada and portions of the Rocky Mountains. High carbon‐density forests in the Pacific coast and western Cascades regions are projected to be the least vulnerable to either drought or fire. Importantly, differences in climate projections lead to only 1% of the domain with conflicting low and high vulnerability to fire and no area with conflicting drought vulnerability. Our drought vulnerability metrics could be incorporated as probabilistic mortality rates in earth system models, enabling more robust estimates of the feedbacks between the land and atmosphere over the 21st century.


What’s New in LANDFIRE: Remap

Webinar Event from Northwest Fire Science Consortium and LANDFIRE

What will you learn?

This webinar seeks to inform participants about what to expect from LANDFIRE Remap products, and what has and has not changed from previous product offerings. We will discuss what we have learned since February 2019 when the products were made available to users in the Northwest, and how LANDFIRE resources can address specific fire and land management issues.

Presenters:

Kori Blankenship, Fire Ecologist and Jim Smith, Program Lead, The Nature Conservancy LANDFIRE Team, Bend OR and Jacksonville FL, respectively.

Session Details: Thursday May 9, 2019 at 1:00pm US/Pacific || Duration: 1.0 hour

Who should participate?

Anyone who is or might be considering using LANDFIRE products to inform fire and vegetation management decisions: researchers, land and project managers, fire and fuel professionals, GIS specialists, scientists, and practitioners.

Register HERE.

Prepare your computer or mobile device in advance: WebEx instructions


Beyond red crowns: complex changes in surface and crown fuels and their interactions 32 years following mountain pine beetle epidemics in south-central Oregon, USA

Authored by T. Woolley; Published 2019

Background

Mountain pine beetle (Dendroctonus ponderosae Hopkins; MPB), a bark beetle native to western North America, has caused vast areas of tree mortality over the last several decades. The majority of this mortality has been in lodgepole pine (Pinus contorta Douglas ex Loudon) forests and has heightened concerns over the potential for extreme fire behavior across large landscapes. Although considerable research has emerged concerning influence of MPB on forest fuels, there has been little work in the climax lodgepole pine forests of south-central Oregon, USA. Specifically, we assessed changes in forest structure and crown and surface fuels across a chronosequence of time since mountain pine beetle (TSB) epidemics in south-central Oregon (1979 to 2008).

Results

We classified four distinct periods in which significant changes occur in fuels: overstory mortality stage (2 to 4 years TSB), standing snag and snag fall stage (5 to 13 years TSB), regeneration stage (14 to 25 years TSB), and overstory recovery stage (26 to 32 years TSB). Multivariate analyses indicated changes in crown fuels and forest structure following MPB epidemics were driven primarily by basal area of live and standing dead trees, canopy bulk density, canopy base height, and canopy height. Substantial declines in canopy bulk density occurred early (2 to 5 yrs) following beetle activity and slowly recovered over time. The pattern of succession of surface fuels following a MPB epidemic was largely determined by changes over time in 10-h, 100-h, and 1000-h fuel loads, in addition to increasing fuel bed depth. The 100-h fuel load increased over the entire 30-year period, while 1000-h fuel load reached an asymptote 14 to 26 years following epidemic initiation. Live woody fuels increased through the initial overstory mortality stage and began to decrease during the overstory recovery stage.

Conclusions

Our key findings concerning changing fuels and forest structure following a MPB epidemic in south-central Oregon lodgepole pine forests include: 1-h fuels and litter changed little over time, surface fuel loads changed dramatically between the standing snag and the regeneration stages, lodgepole pine remained dominant, and canopy bulk density was low throughout the chronosequence. These factors point to the perpetuation of a lodgepole pine dominated system with a mixed-severity fire regime well into the future.


Science in the Sagebrush Steppe

Workshop Event from The Eastern Oregon Agricultural Research Center

The Eastern Oregon Agricultural Research Center is hosting this College Range and Ag Club gathering. College Range and Ag Clubs provide a great conduit to explore career opportunities in the rangeland science field and to begin meeting those who work in this field. At EOARC we conduct extensive rangeland research that becomes “science managers can use” to enhance and improve rangeland management. Through this event, you can meet people making a career in rangeland management, we can learn together about the real issues facing rangeland management, and you will gain some extra experience on the land in a fun setting! We are glad to have you out on the range! 

View the brochure for more information. 


Designing Operationally Relevant Daily Large Fire Containment Strategies Using Risk Assessment Results

Authored by Y. Wei; Published 2019

In this study, we aim to advance the optimization of daily large fire containment strategies for ground-based suppression resources by leveraging fire risk assessment results commonly used by fire managers in the western USA. We begin from an existing decision framework that spatially overlays fire risk assessment results with pre-identified potential wildland fire operational delineations (PODs), and then clusters PODs into a response POD (rPOD) using a mixed integer program (MIP) model to minimize expected loss. We improve and expand upon this decision framework through enhanced fire modeling integration and refined analysis of probabilistic and time-sensitive information. Specifically, we expand the set of data inputs to include raster layers of simulated burn probability, flame length probability, fire arrival time, and expected net value change, all calculated using a common set of stochastic weather forecasts and landscape data. Furthermore, we develop a secondary optimization model that, for a given optimal rPOD, dictates the timing of fire line construction activities to ensure completion of containment line prior to fire arrival along specific rPOD edges. The set of management decisions considered includes assignment of PODs to be included in the rPOD, assignment of suppression resources to protect susceptible structures within the rPOD, and assignment of suppression resources to construct fire lines, on specific days, along the perimeter of the rPOD. We explore how fire manager risk preferences regarding firefighter safety affect optimal rPOD characteristics, and use a simple decision tree to display multiple solutions and support rapid assessment of alternatives. We base our test cases on the FSPro simulation of the 2017 Sliderock Fire that burned on the Lolo National Forest in Montana, USA. The overarching goal of this research is to generate operationally relevant decision support that can best balance the benefits and losses from wildfire and the cost from responding to wildfire.


Engaging fires before they start: Spatial fire planning for the 21st Century

Webinar from Northwest Fire Science Consortium

Chris Dunn, Research Associate in the College of Forestry at Oregon State University, presented "Engaging fires before they start: Spatial fire planning for the 21st Century." Watch the video on our YouTube channel.


Overview & Applications of the PNW Quantitative Wildfire Risk Assessment

Webinar Event from Northwest Fire Science Consortium

What will you learn?

This webinar will focus on the development and use of the all lands Pacific Northwest Quantitative Wildfire Risk Assessment. The presentation will cover agency policy and direction,  what is risk, what data and procedures were used to conduct the assessment, products, lessons learned, and applications to federal, state, county, and local entities.

Presenter:

Rick Stratton, Fire Analyst for the US Forest Service, National Office, Fire and Aviation Management

Session Details: Wednesday, April 24th at 10:00am US/Pacific || Duration: 1.0 hour

Who should participate?

Managers/Practitioners, Scientists/Researchers, Other

Register HERE.

Prepare your computer or mobile device in advance: WebEx instructions