In 28 interviews of experienced wildland firefighters of seven different agencies in Northern Colorado and Southern Wyoming researchers asked them about their observations of fire behavior in beetle-attacked lodgepole pine forests, with a focus on what they considered surprising from a fire behavior standpoint and how this in turn affected their suppression tactics. The interviews focused on 13 wildfires that occurred during the 2010 through 2012 fire seasons.
Below is an excerpt from a paper written by the researchers:
“The surprises in fire behavior experienced by firefighters during the red phase of post-outbreak forests included an elevated level of fire spread and intensity under moderate weather and fuel moisture conditions, increased spotting, and faster surface-to-crown fire transitions with limited or no ladder fuels.
“Unexpectedly, during the gray phase in mountain pine beetle-attacked stands, crown ignition and crown fire propagation was observed for short periods of time. Firefighters are now more likely to expect to see active fire behavior in nearly all fire weather and fuel moisture conditions, not just under critically dry and windy situations, and across all mountain pine beetle attack phases, not just the red phase. Firefighters changed their suppression tactics by adopting indirect methods due to the potential fire behavior and tree-fall hazards associated with mountain pine beetle-attacked lodgepole pine forests.”
The project would take place in the Medicine Bow National Forest in southern Wyoming
The U.S. Forest Service has a plan to treat 360,000 acres in the Medicine Bow National Forest in southern Wyoming by logging, thinning, prescribed burning, and building 600 miles of roads. The justification for what they are calling the Landscape Vegetation Analysis project, or LaVA, is to treat areas in the forest with the intention of “restoring forest health”. This area just north of the Colorado/ Wyoming border has been heavily impacted by Mountain Pine Beetles, so it fits the agency’s definition of an unhealthy forest and is considered by the U.S. Forest Service as an undesirable condition.
The Forest Service intends to build 600 miles of roads, clear cut 95,000 acres, selectively cut or commercially thin 165,000 acres, and use prescribed fire, mastication, and hand thinning on 100,000 acres.
Climate change that brought drought and warmer weather has provided a better habitat for the beetles. During normal times their spread is inhibited in the higher elevations by cold winters. Several days with low temperatures of around 35 degrees below zero can knock them back, but if that does not occur the rice-sized insects can come back with a vengeance the next summer.
Beetle-killed trees can be hazardous to firefighters due to the possibility of falling trees and burning snags. And, 5 to 15 years after the outbreak heavy ground fuels make fireline construction difficult. The dead trees can also be problematic near roads, trails, and structures. But a couple of years after the beetle attack and the red needles have been shed, the tree skeletons are less prone to crown fires than green trees. In 2015 University of Colorado Boulder researcher Sarah Hart determined Western U.S. forests killed by the mountain pine beetle epidemic are no more at risk to burn than healthy Western forests. Other scientists have found similar results.
Not everyone considers the plan a good idea. Some biologists say science doesn’t back up the efficacy of the treatments proposed, particularly logging and the prescribed burns that the Forest Service calls necessary for lodgepole pine to reproduce and more diverse species to take root.
“They say they are going to reduce fuel loads to limit wildfires, and the literature doesn’t support that,” said Daniel B. Tinker, an associate professor at the University of Wyoming, who has studied the region for 23 years. “We’ve had fires this summer that burned through areas that were clear-cut 15 years ago. Those stands weren’t supposed to burn for 100 years.”
Conservation groups also say the Forest Service truncated scientific review in a rush to meet congressional demands for increased timber production on public lands. For now, the proposal does not specify which parcels would be targeted and where those hundreds of miles of road would be built.
In the Washington Post, article Andy Stahl, executive director of Forest Service Employees for Environmental Ethics, was quoted as saying “Certainly, prescribed burning doesn’t pay its way — it’s expensive at around $100,000 per acre.”
If there is a prescribed fire somewhere that actually cost $100,000 an acre, which is very hard to believe, it is definitely an outlier. The costs vary greatly across the country and by vegetation type. They can be as inexpensive as less than a dollar an acre in Oklahoma, but usually run $10 to $250 an acre.
The federal agencies have had to cut back on their prescribed burning programs in recent years due to budget reductions.
The Forest Service expects to make a decision on the Medicine Bow plan in mid-2019.
Thanks and a tip of the hat go out to Gary. Typos or errors, report them HERE.
And as before when the Secretary and the President said “poor forest management” and “environmental radicals” are responsible for the recent major fires in California, the issue can’t be described or solutions offered using just a few words. It is nuanced and complicated, not lending itself to a 280-character conversation.
In 2010 I first became aware of research by scientists that found fire severity decreases following an attack by mountain pine beetles. Since then additional studies have led to a more thorough understanding of the process.
Three factors or characteristics of a beetle-killed forest affect the behavior of a wildland fire.
After a tree is killed by a mountain pine beetle, the needles turn brown or red; this is known as the “red stage”. The dead red needles remain on the tree for one or two years and then fall off. During this period the potential for a crown fire that moves above the ground through the tops or crowns of the trees can increase. After the needles drop the potential for a crown fire is close to zero. A crown fire can’t be controlled. No amount of fire retardant dropped by aircraft, water applied from the ground, or dozers building fire lines will stop it. This is the largest factor to consider when discussing fire behavior before and after a beetle outbreak. After a couple of years, it is easier to control a fire in a beetle-affected forest than one that is green, and this effect lasts for decades. There are other factors to consider also.
After 5 to 15 years the limbs begin to break off a beetle-killed tree and then the top can break off and eventually the remainder of the tree falls to the ground. This adds fuel to the forest floor and can increase the intensity of a fire that burns along the ground. It is easier to control a surface fire, even one burning intensely, than a crown fire .
After a decade or two the potential for individual or multiple tree torching can increase. This involves the burning of an entire standing single tree or multiple trees. These latter two issues, surface fire intensity and torching, add to the challenges for firefighters, but the reduced crown fire potential greatly outweighs the other two.
This can be distilled into what I have called Resistance to Control (RTC) which considers those three characteristics of a beetle-killed forest. One to two years after the insect-attacked tree dies, the RTC increases, but after that it decreases immediately and remains lower than before the attack for several decades. Eventually live trees replace the dead ones and all three characteristics return to their normal state.
The chart below summarizes these three issues. It is from a paper titled Effects of bark beetle-caused tree mortality on wildfire, written by Jeffrey A. Hicke, Morris C. Johnson, Jane L. Hayes, and Haiganoush K. Preisler. With apologies to the authors of this very good research paper, I took the liberty of adding a Resistance To Control variable (the red line) to their chart.
There is still another characteristic of a beetle-killed forest that is important to consider. Pine beetle outbreaks do not automatically lead to catastrophic wildfires. In 2015 University of Colorado Boulder researcher Sarah Hart determined Western U.S. forests killed by the mountain pine beetle epidemic are no more at risk to burn than healthy Western forests. Other scientists have found similar results.
Mr. Zinke referred to a forest with evidence of tree mortality caused by insects as a forest that is not healthy. Insects are part of the ecosystem; they will always be part of the forests. We will never be able to eradicate them, nor should we. The populations of the insects run in cycles. They feed on trees to survive.
In addition, the “dead and dying timber” as a result of fires or insects that Mr. Zinke wants to remove is an integral part of the forest ecosystem. The National Wildlife Federation says, “Dead trees provide vital habitat for more than 1,000 species of wildlife nationwide. They also count as cover and places for wildlife to raise young.”
An article at The Hill November 20 covers how Mr. Zinke and Secretary of Agriculture Sonny Perdue are hoping that the new version of the Farm Bill will allow more logging that among other objectives, “beautifies the forests”, as Mr. Zinke is quoted as saying.
Roy Renkin, a Yellowstone National Park Vegetation Management Specialist, wrote in 2010, “Disturbances like insect outbreaks and fire are recognized to be integral to the health of the forests,” he said, “and it has taken ecologists most of this century to realize as much. Yet when these disturbances occur, our emotional psyche leads us to say the forests are ‘unhealthy.’ Bugs and fires are neither good nor bad, they just are.”
This week a group of nine scientists and researchers published the results of their work considering how unusually high tree mortality affects wildfires in California’s Sierra Nevada forests that over thousands of years have adapted to frequent fire. They point out that fire suppression-caused forest densification has increased competition among trees for water and other resources, destabilizing many frequent fire forests by making them prone to mortality from other agents such as bark beetles.
Scott L. Stephens, Brandon M. Collins, Christopher J. Fettig, Mark A. Finney, Chad M. Hoffman, Eric E. Knapp, Malcolm P. North, Hugh Safford, Rebecca B. Wayman
Massive tree mortality has occurred rapidly in frequent-fire-adapted forests of the Sierra Nevada, California. This mortality is a product of acute drought compounded by the long-established removal of a key ecosystem process: frequent, low- to moderate-intensity fire. The recent tree mortality has many implications for the future of these forests and the ecological goods and services they provide to society. Future wildfire hazard following this mortality can be generally characterized by decreased crown fire potential and increased surface fire intensity in the short to intermediate term. The scale of present tree mortality is so large that greater potential for “mass fire” exists in the coming decades, driven by the amount and continuity of dry, combustible, large woody material that could produce large, severe fires. For long-term adaptation to climate change, we highlight the importance of moving beyond triage of dead and dying trees to making “green” (live) forests more resilient.
Unprecedented Sierra Nevada tree mortality has rapidly occurred after a severe drought with effects compounded by forest densification from decades of fire suppression. In the central and southern Sierra Nevada some areas have experienced more than 90% tree mortality, producing extensive landscapes of standing dead trees. This differs from mortality resulting from stand-replacing wildfire because bark beetles do not reduce surface fuels or jumpstart succession of shade-intolerant, fire-resistant pines. Forest managers have been struggling to determine whether these new postmortality conditions will increase wildfire intensity and/or severity, what the near- and long-term effects on forest communities will be, and what the appropriate intervention measures are.
In the first decade, wildfire severity in bark beetle killed frequent fire (FF) forests may be little affected over current conditions. Other than a brief increase during the “red phase” when most dead needles are still on recently killed trees, the reduction in canopy fuels is counterbalanced by an increase in surface fuels (figure 2). However, these are no grounds for complacency because current conditions in the majority of mixed-conifer and yellow pine forests in California already consist of unnaturally high surface fuel loads and corresponding elevated fire hazards (figure 2; Lydersen et al. 2014, Stephens et al. 2015).
The more troubling projection is how extensive loading of large-sized woody fuels in future decades may contribute to dangerous mass fires beyond the predictive capacity of current fire models. These fires can generate their own wind and weather conditions and create extensive spotting, making fire behavior and its impact on structures and public safety difficult to manage and predict. In addition, such intense fires could prevent forests from becoming re-established. Lacking the legacy of live trees that historic FF would have left (Stephens et al. 2008), large unburned areas of dead trees may also produce unusual forest succession patterns. These patterns will likely favor shade-tolerant and hardwood tree regeneration, limited shrub growth, and accumulating large woody fuels that would likely kill regenerating forests when wildfire inevitably occurs. The scale of contiguous tree mortality entrenches the homogeneity produced by fire suppression, reducing the fine-scale heterogeneity of forest conditions that contributes to resilience and biodiversity. Management could enhance adaptation to climate-change-induced stress if it focused more of its resources on creating spatially and temporally variable patterns in green FF forests that are better aligned with local moisture availability and fire patterns (North et al. 2009).
Many of our FF forests have failed to receive the very management that could increase resilience to disturbances exacerbated by climate change, such as the application of prescribed fire and mechanical restoration treatments (Stephens et al. 2016). Recent tree mortality raises serious questions about our willingness to address the underlying causes. If our society doesn’t like the outcomes from recent fires and extensive drought-induced tree mortality in FF forests, then we collectively need to move beyond the status quo. Working to increase the pace and scale of beneficial fire and mechanical treatments rather than focusing on continued fire suppression would be an important step forward.
The WSB and MPB attack trees very differently. The WSB defoliates the tree, consuming the needles and removing fuel from the canopy relatively quickly. The MPB kills the tree from the inside, leaving the dying “red” needles on the tree until they fall off in one to two years. The possibility of crown fires may increase during that red needle period, but it makes sense that fewer fine fuels in the canopy would reduce the fire intensity and make it less prone to transition from a ground fire to a crown fire. Both types of attacks eventually produce more course fuel on the forest floor as the branches break off and the trees eventually fall over.
Research conducted by Daniel G. Gavin, Aquila Flower, Greg M. Cohn, Russell A. Parsons, and Emily K. Heyerdahl found evidence of a “fire proofing effect” for outbreaks of WSB. It does not address the MPB.
Below is an excerpt from their work:
“Extrapolating Results: Reduced Tree Mortality
“Taken together, the tree-ring and modeling studies suggest a lack of synergism between WSB outbreaks and wildland fires. However, a different kind of synergism may exist: Defoliation might dampen the severity of a subsequent wildfire. To explore this possibility, we used existing empirical equations that show the probability of mortality due to defoliation (fig. 3A) and the probability of mortality due to crown scorch (fig. 3B), combined with the simulated results of canopy consumption at different levels of defoliation (fig. 3C), to extrapolate the summed probability of mortality under a range of surface fire intensities and defoliation levels (fig. 3D). The results suggested a distinct “fireproofing” effect of defoliation: The increased risk of mortality by WSB is more than compensated for by reduced foliage consumption during moderate surface fire intensities. For example, trees with 50-percent defoliation have a distinctly lower probability of mortality when surface fires are less than about 74 kilowatts per square foot (800 kW/m2 ).
“However, we considered only the partial effect of defoliation on fire occurrence; we did not take into account other effects of WSB outbreaks, such as mortality of small trees. Of course, field observations are required to test our prediction. Remotely sensed burn severity maps, in combination with prior surveys of insect effects, could address this issue. One such study of the 2003 B&B Complex Fire in Oregon showed that prior defoliation had a marginal effect on reducing fire severity that was not statistically significant (Crickmore 2011). However, an analysis by Meigs and others (2016) of all post-WSB fires in Washington and Oregon from 1987 to 2011 showed that there is a statistically significant reduction in fire severity that persists for up to 20 years following an outbreak. Thus, the effect of defoliation on crown fire behavior modeled by Cohn and others (2014) appears to be confirmed by the analysis of burn severity data by Meigs and others (2016).
“It may seem reasonable to assume that extensive defoliation, causing sustained low levels of tree mortality in mature trees, should have a measurable effect on wildfire occurrence. However, fire is a highly variable disturbance in itself, and it is highly sensitive to specific climate and winds during the fire event. The scale of fuel changes wrought by WSB may be too small to affect subsequent fire probability in ecosystems where fire is limited by fuel moisture and ignition sources rather than fuel availability. Our data show that these two disturbance types do not share similar histories, despite a common link to drought events.
“Nevertheless, we hypothesize a “fireproofing” effect on host trees from defoliation due to WSB outbreaks. Although such an effect has been detected statistically from recent fire events (Preisler and others 2010; Meigs and others 2016), the inferred processes at play remain to be studied in detail at the site scale.”
California has fewer inmates available for fighting wildfires
With fewer inmates available for fighting fires, the state of California is turning to civilian crews within their Conservation Corps.
…But the number of available inmates is declining because counties now oversee most lower-level felons under a law aimed at easing prison overcrowding. In addition, there are fewer incentives for inmates to risk their lives since a federal court broadened an early release program for firefighters to include other inmates.
The state is about 600 inmates short of the 4,300 prisoners who could be available for fire lines. So this year, the California Conservation Corps reopened a camp to train three crews of young civilians to do the same backbreaking work as the inmates. Corps Director Bruce Saito expects to create at least four more fire crews with roughly 15 members each by next summer and a half-dozen new crews during each of the next two years.
The corps has more than 1,400 members, but fewer than 200 currently work alongside local, state and federal firefighters battling blazes in rural areas.
The members include both men and women and range in age from 18 to 25. They enlist for one year and earn the state’s minimum wage of $10 an hour. Military veterans can enroll until they turn 30…
Oregon sues 3 people responsible for starting the Ferguson Fire
Oregon hopes to recover $892,082 from three individuals who they say are responsible for starting the Ferguson Fire that burned 200 acres and destroyed two structures in Klamath County in July 2014.
The suit alleges that Joe Askins started a campfire, then took a nap. When he awoke, the campfire had escaped. Askins also said “I’ll take all the blame for the fire,” according to the lawsuit.
More evidence that beetle-killed forests do not increase the risk of catastrophic wildfires.
An article at News Deeply summarizes several research studies which mostly concluded that beetle-killed forests do not burn more severely than forests that have not been attacked by the insects. This is in spite of statements to the contrary by the Secretary of Agriculture, a spokesperson for CAL FIRE, and media stories about trees that are now part of a “tinder box”.
Air tanker 132 starts contract in Australia
Fire Aviation reports that Coulson’s Air Tanker 132 started its contract with New South Wales on September 6, helping to provide air support for wildland firefighters in Australia. This is the second year in a row that the L-382G, a variant of the C-130 platform, has worked down under during their summer bushfire season.
Cheyenne is concerned about the effects of the Snake Fire on their water system
“The location of the fire is close proximity to our major watershed collection area for the Hog Park Reservoir” said Dena Egenhoff, the Board of Public Utilities’ (BOPU) Water Conservation Manager. “We are unable to know the impact of the Snake Fire at this time, but the location suggests there may be some adverse impacts to the City of Cheyenne’s water collection system.” As of September 11, 2016, the Hog Park Reservoir is 91.8% full
For Cheyenne, BOPU collects water in the Little Snake River drainage from snow melt and streams and transports it under a mountain by a tunnel to the eastside of the Continental Divide. That water is then stored in Hog Park Reservoir. From there, the collected water from Hog Park Reservoir is traded for water in Rob Roy Reservoir which can more easily be transported without pumping to Cheyenne. “In this way, the amount of water can be exchanged between the two different Mountain Ranges with all water rights being satisfied,” said Dena Egenhoff.
The Snake fire is in south-central Wyoming just north of the Colorado border. It is 115 air miles miles west of Cheyenne, and 20 miles west of the 38,000-acre Beaver Creek Fire that has been burning in Colorado and Wyoming since July 19, 2016.