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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.

 Starker Lecture

This year's Starker lectures, now available online, offer individuals, neighborhoods, and communities useful information and strategies for living in a changing environment. Check out the video archive now!

Hot Topics


Ignition patterns influence fire severity and plant communities in Pacific Northwest, USA, prairies

Authored by A. Martin; Published 2016

In the prairies of the Pacific Northwest, USA, fire has been reintroduced as a tool for reducing non-native, invasive plant cover and promoting the growth and establishment of native plant communities.  Head fires and backing fires are the two primary ignition patterns used to complete most prescribed burns, but the relative effectiveness of these two methods on invasive plant control and native enhancement is unknown.  A clear understanding of the relationship between fire behavior, fire severity, and fire effects on vegetation and how these metrics are affected by fire ignition patterns could help managers fine tune burn prescriptions to better achieve ecological objectives.  We used observations from five prescribed burns in the south Puget Sound prairies of western Washington, USA, to evaluate the relationship between intensity, severity, and effects.  Additionally, we collected data from two burns on how ignition patterns affected these relationships.  We found a significant positive correlation between maximum surface temperature and fire severity, and a decline in perennial taxa with increasing fire severity.  We also found that surface temperatures did not differ between ignition patterns, but a greater area burned at moderate severity in backing fires than in head fires.  Ignition patterns differentiated plant communities by changing the number of species present within different life form categories.  However, this response was contingent upon site history and pre-burn conditions.  Native perennial forbs were associated with head fires in a site with high pre-existing native plant species richness.  Native and exotic forbs were associated with backing fires at a site with low pre-existing native plant species richness.  Thus, managers may want to consider ignition patterns when planning burn prescriptions in order to achieve particular ecological objectives.


NWFSC Fire Facts: What is? Red Flag Warning

Authored by N.W.Fire Scien Consortium; Published 2016

A Red Flag Warning is issued by the National Weather Service (NWS) to alert land management agencies about the onset, or possible onset, of critical weather and fuel moisture conditions that could lead to rapid or dramatic increases in wildfire activity. Read more at Fire Facts: What is? Red Flag Warning


Forest fuels and potential fire behaviour 12 years after variable-retention harvest in lodgepole pine

Authored by J.S. Crotteau; Published 2016

Variable-retention harvesting in lodgepole pine offers an alternative to conventional, even-aged management. This harvesting technique promotes structural complexity and age-class diversity in residual stands and promotes resilience to disturbance. We examined fuel loads and potential fire behaviour 12 years after two modes of variable-retention harvesting (dispersed and aggregated retention patterns) crossed by post-harvest prescribed fire (burned or unburned) in central Montana. Results characterise 12-year post-treatment fuel loads. We found greater fuel load reduction in treated than untreated stands, namely in the 10- and 100-h classes (P = 0.002 and 0.049 respectively). Reductions in 1-h (P < 0.001), 10-h (P = 0.008) and 1000-h (P = 0.014) classes were greater in magnitude for unburned than burned treatments. Fire behaviour modelling incorporated the regenerating seedling cohort into the surface fuel complex. Our analysis indicates greater surface fireline intensity in treated than untreated stands (P < 0.001), and in unburned over burned stands (P = 0.001) in dry, windy weather. Although potential fire behaviour in treated stands is predicted to be more erratic, within-stand structural variability reduces probability of crown fire spread. Overall, results illustrate trade-offs between potential fire attributes that should be acknowledged with variable-retention harvesting.


Synthesis of Knowledge of Extreme Fire Behavior: Volume II for Fire Behavior Specialists, Researchers, and Meteorologists

Authored by P.A. Werth; Published 2016

The National Wildfire Coordinating Group’s definition of extreme fire behavior indicates a level of fire behavior characteristics that ordinarily precludes methods of direct control
action. One or more of the following is usually involved: high rate of spread, prolific crowning/ spotting, presence of fire whirls, and strong convection column. Predictability is difficult
as such fires often influence their environment to some degree and behave erratically, sometimes dangerously. Alternate terms include “blow up” and “fire storm.” Fire managers
examining fires over the last 100 years have come to understand many of the factors necessary for extreme fire behavior development. This effort produced guidelines included in
current firefighter training, which presents the current methods of predicting extreme fire behavior by using the crown fire model, which is based on the environmental influences of
weather, fuels, and topography. Current training does not include the full extent of scientific understanding nor does it include the most recent scientific knowledge. National Fire Plan funds and the Joint Fire
Science Program have sponsored newer research related to wind profiles’ influence on fire behavior, plume growth, crown fires, fire dynamics in live fuels, and conditions associated
with vortex development. Of significant concern is that characteristic features of extreme fire behavior depend on conditions undetectable on the ground, namely invisible properties
such as wind shear or atmospheric stability. No one completely understands all the factors contributing to extreme fire behavior because of gaps in our knowledge. These gaps, as well as the limitations as to when various
models or indices apply should be noted to avoid application where they are not appropriate or warranted. This synthesis summarizes existing extreme fire behavior knowledge. It
consists of two volumes. Volume 1 is for fire managers, firefighters, and others in the fire community who are not experts or specialists in fire behavior but need to understand the
basics of extreme fire behavior. Volume 2 is more technical and is intended for fire behaviorists and fire researchers.


Do insect outbreaks reduce the severity of subsequent forest fires?

Authored by G.W. Meigs; Published 2016

Understanding the causes and consequences of rapid environmental change is an essential scientific frontier, particularly given the threat of climate- and land use-induced changes in disturbance regimes. In western North America, recent widespread insect outbreaks and wildfires have sparked acute concerns about potential insect–fire interactions. Although previous research shows that insect activity typically does not increase wildfire likelihood, key uncertainties remain regarding insect effects on wildfire severity (i.e., ecological impact). Recent assessments indicate that outbreak severity and burn severity are not strongly associated, but these studies have been limited to specific insect or fire events. Here, we present a regional census of large wildfire severity following outbreaks of two prevalent bark beetle and defoliator species, mountain pine beetle (Dendroctonus ponderosae) and western spruce budworm (Choristoneura freemani), across the US Pacific Northwest. We first quantify insect effects on burn severity with spatial modeling at the fire event scale and then evaluate how these effects vary across the full population of insect–fire events (n = 81 spanning 1987–2011). In contrast to common assumptions of positive feedbacks, we find that insects generally reduce the severity of subsequent wildfires. Specific effects vary with insect type and timing, but both insects decrease the abundance of live vegetation susceptible to wildfire at multiple time lags. By dampening subsequent burn severity, native insects could buffer rather than exacerbate fire regime changes expected due to land use and climate change. In light of these findings, we recommend a precautionary approach when designing and implementing forest management policies intended to reduce wildfire hazard and increase resilience to global change.


Incorporating Anthropogenic Influences into Fire Probability Models: Effects of Human Activity and Climate Change on Fire Activity in California

Authored by M.L. Mann; E. Batllori; M.A. Moritz; E.K. Waller; P. Berck; A.L. Flint; L.E. Flint; E. Dolfi; Published 2016

The costly interactions between humans and wildfires throughout California demonstrate the need to understand the relationships between them, especially in the face of a changing climate and expanding human communities. Although a number of statistical and process-based wildfire models exist for California, there is enormous uncertainty about the location and number of future fires, with previously published estimates of increases ranging from nine to fifty-three percent by the end of the century. Our goal is to assess the role of climate and anthropogenic influences on the state’s fire regimes from 1975 to 2050. We develop an empirical model that integrates estimates of biophysical indicators relevant to plant communities and anthropogenic influences at each forecast time step. Historically, we find that anthropogenic influences account for up to fifty percent of explanatory power in the model. We also find that the total area burned is likely to increase, with burned area expected to increase by 2.2 and 5.0 percent by 2050 under climatic bookends (PCM and GFDL climate models, respectively). Our two climate models show considerable agreement, but due to potential shifts in rainfall patterns, substantial uncertainty remains for the semiarid inland deserts and coastal areas of the south. Given the strength of human-related variables in some regions, however, it is clear that comprehensive projections of future fire activity should include both anthropogenic and biophysical influences. Previous findings of substantially increased numbers of fires and burned area for California may be tied to omitted variable bias from the exclusion of human influences. The omission of anthropogenic variables in our model would overstate the importance of climatic ones by at least 24%. As such, the failure to include anthropogenic effects in many models likely overstates the response of wildfire to climatic change.


The Passing of the Lolo Trail, with an Introduction by Andrew J. Larson

Authored by E. Koch; Published 2016

In 1935, Elers Koch argued in a Journal of Forestry article that a minimum fire protection model should be implemented in the backcountry areas of national forests in Idaho, USA.  As a USDA Forest Service Supervisor and Assistant Regional Forester, Koch had led many major fire-fighting campaigns in the region, beginning with the great 1910 fires of Idaho and Montana.  He argued in his classic article for wilderness values, and against throwing millions of dollars into unsuccessful attempts to suppress backcountry fires.  His article was accompanied by a response from Earl Loveridge, a proponent of full fire suppression, who was a leader of fire control from the Forest Service Washington Office.  Loveridge soon after successfully proposed what was to become known as the 10 AM Policy—a universal fire suppression policy that lasted into the 1970s.  While Koch’s classic article was not immediately successful in bringing about the backcountry “let burn” fire policy he sought, it did contribute to the designation of the Selway-Bitterroot Primitive Area in 1936, which became a congressionally designated wilderness area in 1964 with the passing of the Wilderness Act.  With that, the stage was set for a new era in Forest Service fire management, and in 1972 the White Cap Creek drainage in the Selway-Bitterroot Wilderness became the first exception to the 10 AM Policy, realizing Koch’s vision.


NWFSC Fire Facts: The National Cohesive Strategy

Authored by N.W.Fire Scien Consortium; Published 2016

The National Cohesive Wildland Fire Management Strategy is a collaboration effort involving federal and state agencies, local governments, tribes, and interested stakeholders throughout the nation to improve coordination across the various jurisdictions for managing wildfire. Read more at Fire Facts: What is? The National Cohesive Strategy


Southwest Fire Season: 2015 Overview & 2016 Outlook

Please join us for a webinar to review last year’s fires and look ahead toward conditions for this year. Dr. Zander Evans will present an overview of the 12 largest fires in the Southwest during 2015. He will share summaries of forest types and burn severities for each of the 12 fires. In addition, Brent Wachter, Fire Weather Meteorologist with NOAA, will discuss the fire season outlook for this year in the Southwest. Click here to register for this webinar NOW!


The interagency fuels treatment decision support system: Functionality for fuels treatment planning

Authored by S.A. Drury; Published 2016

The Interagency Fuels Treatment Decision Support System (IFTDSS) is a web-based software and data integration framework that organizes fire and fuels software applications into a single online application. IFTDSS is designed to make fuels treatment planning and analysis more efficient and effective. In IFTDSS, users can simulate fire behavior and fire effects using the scientific algorithms and processes found in desktop applications including FlamMap, Behave, FOFEM, and Consume. Strategic-level goals of IFTDSS are to
• simplify the fuels treatment planning decision-support process;
• improve the overall quality of analysis and planning;
• control long-term costs;
• encourage scientific collaboration;
• reduce agency information technology (IT) workload in deploying and maintaining fuels applications and data; and
• promote interagency collaboration within the fire and fuels community.

This paper discusses the tools and processes IFTDSS offers to fire, fuels, and resource managers responsible for planning fuels treatment within a framework of hazard analysis and risk assessment. We outline how fire and
fuels treatment planners can use IFTDSS to identify areas of high hazard and risk, evaluate the potential burning risk and hazard level for valued resources (values at risk) within the area of interest, and simulate the effectiveness of fuels treatments in reducing the potential harm to values at risk.


Outcomes of fire research: is science used?

Authored by M.E. Hunter; Published 2016

An assessment of outcomes from research projects funded by the Joint Fire Science Program was conducted to determine whether or not science has been used to inform management and policy decisions and to explore factors that facilitate use of fire science. In a web survey and follow-up phone interviews, I asked boundary spanners and scientists about how findings from a random sample of 48 projects had been applied and factors that acted as barriers or facilitators to science application. In addition, I conducted an investigation of recent planning documents to determine whether products from the sampled projects were cited. All lines of evidence suggest that information from most (44 of 48) of these projects have been used by fire and fuels managers in some capacity. Science has mostly been used during planning efforts, to develop treatment prescriptions, and to evaluate current practices. Lack of manager awareness was commonly identified as a barrier to application of science. Conversely, activities and organisations that foster interaction between scientists and managers were identified as facilitating the application of science. The efforts of the Joint Fire Science Program to communicate science findings and engage managers has likely contributed to the application of fire science.


Vegetation Response to Piñon and Juniper Tree Shredding

Authored by J. Bybee; Published 2016

Piñon (Pinus spp.) and juniper (Juniperus spp.) expansion and infilling in sagebrush (Artemisia L.) steppe communities can lead to high-severity fire and annual weed dominance. To determine vegetation response to fuel reduction by tree mastication (shredding) or seeding and then shredding, we measured cover for shrub and herbaceous functional groups on shredded and adjacent untreated areas on 44 sites in Utah. We used mixed model analysis of covariance to determine significant differences among ecological site type (expansion and tree climax) and treatments across a range of pretreatment tree cover as the covariate. Although expansion and tree climax sites differed in cover values for some functional groups, decreasing understory cover with increasing tree cover and increased understory cover with tree reduction was similar for both ecological site types. Shrub cover decreased by 50% when tree cover exceeded 20%. Shredding trees at ≤ 20% cover maintained a mixed shrub (18.6% cover)−perennial herbaceous (17.6% cover) community. Perennial herbaceous cover decreased by 50% when tree cover exceeded 40% but exceeded untreated cover by 11% (20.1% cover) when trees were shredded at 15−90% tree cover. Cheatgrass (Bromus tectorum L.) cover also increased after tree shredding or seeding and then shredding but was much less dominant (< 10% cover) where perennial herbaceous cover exceeded 42%. Sites with high cheatgrass cover on untreated plots had high cheatgrass cover on shredded and seeded-shredded plots. Seeding and then shredding decreased cheatgrass cover compared with shredding alone when implemented at tree cover ≥ 50%. Vegetation responses to shredding on expansion sites were generally similar to those for tree cutting treatments in the SageSTEP study. Shredding or seeding and then shredding should facilitate wildfire suppression, increase resistance to weed dominance, and lead toward greater resilience to disturbance by increasing perennial herbaceous cover.