Forest Science
ABSTRACT: From the Proceedings of the National Academy of Sciences, April 7, 2015 edition.
Across western North America, abundant susceptible pine hosts and a suitable climate during the early 21st century have promoted widespread mountain pine beetle (MPB) outbreaks, leading to concern that dead fuels may increase wildfire risk. The assumption that outbreaks raise fire risk is driving far-reaching policy decisions involving expenditures of hundreds of millions of dollars. Contrary to the expectation that an MPB outbreak increases fire risk, spatial overlay analysis shows no effect of outbreaks on subsequent area burned during years of extreme burning across the West. These results refute the assumption that increased bark beetle activity has increased area burned; therefore, policy discussions should focus on societal adaptation to the effects of the underlying drivers: warmer temperatures and increased drought.
The results demonstrate that the annual area burned in the western United States has not increased in direct response to bark beetle activity. Therefore, policy discussions should focus on societal adaptation to the effects of recent increases in wildfire activity related to increased drought severity.
ABSTRACT: There is significant debate about restoration targets for ponderosa pine (Pinus ponderosa) and mixed-conifer forests in the Sierra Nevada, California, USA. On one side are recommendations to create both extensive open and park-like pine forests, and to reduce high-severity fire occurrence by mechanical thinning of forests. These recommendations drive current management. On the other side are recommendations to manage landscapes for both dense, old forest, and complex early-seral forest that is created by both high-severity and moderate-severity fires characteristic of historical fire regimes.
Our research suggests that the latter approach may best maintain forest associated with two imperiled species that are top management concerns of federal agencies in the Sierra Nevada: the California Spotted Owl (Strix occidentalis occidentalis) and the Pacific Fisher (Pekania pennanti). We used spatially extensive US Forest Service forest survey data from 1910 and 1911, and synthesized research from other parts of this region for comparison, to assess reference conditions in low/mid-elevation Sierra Nevada forests. We found that historical ponderosa pine and mixed-conifer forests had a mixed-severity fire regime, with an average of 26% high-severity fire effects, and varied more widely in species composition and density than suggested by previous research. Our findings are contrary to other reports using a very small subset (~6%) of the available data from these same 1910 and 1911 surveys. Therefore, we suggest that historical reference conditions of forests in the Sierra Nevada range of these species are not like that reported previously in other studies, and that mixed-severity fire, and forests defined by strong contrasts and dynamic natural processes, were characteristic of historical ponderosa pine and mixed-conifer forests of the western Sierra Nevada. Our analysis indicates that managing for both dense, old forests, and protecting complex early-seral forest created by high-severity fire, will likely advance conservation and recovery of the Spotted Owl and Pacific Fisher, while current management direction may exacerbate threats.
ABSTRACT The Pacific fisher (Pekania pennanti) is a rare and imperiled forest carnivore, with a genetically distinct and isolated population living in the southern Sierra Nevada mountains of California, USA. Female fishers are of special interest and concern, given their very small numbers and their disproportionately important role in the potential recovery of the population. Using fisher scat detection to assess patterns of habitat use, I conducted analyses regarding use by fishers of unlogged higher severity fire areas at 10–11 years postfire in the 2002 McNally fire area. Contrary to the prevailing current hypothesis regarding fisher postfire habitat use, fishers did not use higher severity fire areas less than low–moderate-severity areas or unburned forest (n¼77 scats), and female fishers used the large, intense McNally fire area significantly more than unburned forest (n¼12 scats). Female fishers were detected at multiple locations >250m into the interior of a very large (>5,000 ha), unlogged higher severity fire patch. These results indicate unlogged higher severity fire areas are suitable habitat for fishers, especially female fishers, and suggest a need to revisit current management direction, which emphasizes extensive commercial thinning and postfire logging to reduce fuels and control fire. © 2015 The Wildlife Society.
After severe wildfires, pine recovery depends on ectomycorrhizal (ECM) fungal spores surviving and serving as partners for regenerating forest trees. We took advantage of a large, severe natural forest fire that burned our long-term study plots to test the response of ECM fungi to fire. We sampled the ECM spore bank using pine seedling bioassays and high-throughput sequencing before and after the California Rim Fire. We found that ECM spore bank fungi survived the fire and dominated the colonization of in situ and bioassay seedlings, but there were specific fire adapted fungi such as Rhizopogon olivaceotinctus that increased in abundance after the fire. The frequency of ECM fungal species colonizing pre-fire bioassay seedlings, post-fire bioassay seedlings and in situ seedlings were strongly positively correlated. However, fire reduced the ECM spore bank richness by eliminating some of the rare species, and the density of the spore bank was reduced as evidenced by a larger number of soil samples that yielded uncolonized seedlings. Our results show that although there is a reduction in ECM inoculum, the ECM spore bank community largely remains intact, even after a high-intensity fire. We used advanced techniques for data quality control with Illumina and found consistent results among varying methods. Furthermore, simple greenhouse bioassays can be used to determine which fungi will colonize after fires. Similar to plant seed banks, a specific suite of ruderal, spore bank fungi take advantage of open niche space after fires. The ISME Journal advance online publication, 16 October 2015; doi:10.1038/ismej.2015.182
Abstract: The Pacific fisher (Martes pennanti) is a rare forest carnivore strongly associated with dense, old forest with high canopy cover for denning and resting. The Sierra Nevada population is very small, genetically distinct, and isolated. Mixed-severity wildland fire is assumed to be a potentially greater threat than logging, and land managers are conducting large-scale forest thinning operations under the hypothesis that it is needed to reduce fire spread and severity. However, the relationship between fishers and fire has not been tested previously. I investigated this question with teams of dogs specially trained to detect the scat of Pacific fishers and, thus, their concentration of movements and habitat use. All scat samples were genetically verified. In surveys on the Kern Plateau in the southwestern Sierra Nevada, within unlogged post-fire forests with mixed-severity effects from large fires, and in unburned forests, I found that fishers selected Sierran mixed-conifer forests in both post-fire and unburned areas, and selected closed-canopied, mature/old forest in unburned forests, as well as burned forests that had this structure in the pre-fire condition. When fishers were near burned/unburned edges, they selected the within-fire side. Fishers used dense, mature/old forest that experienced moderate/high-severity fire at the same level as unburned dense, mature/old forest, and both males and females were found deep inside large fires—several km from the fire perimeter. These results indicate that fishers may benefit from the structural complexity of such post-fire habitat for foraging. This suggests mixed-severity wildland fire could be restored through managed wildland fire in these forests.
Although there has been renewed interest in attempting to boost runoff from Sierra Nevada watersheds by removing copious amounts of forest cover, recent assessments promoting the approach have not given ample attention to well-known factors that sharply limit its utility for augmenting water supplies. These assessments have also largely ignored the considerable and enduring environmental costs of pursuing such an approach.

This report provides a more thorough assessment of the environmental costs and limited utility for water supply from attempts to increase water yield via forest removal in the Sierra Nevada. Although data are limited from the Sierra Nevada, there is considerable body of information from applicable studies throughout the western U.S. that provides a context for assessing the limited benefits and significant costs of pursuing a forest removal or thinning
management approach.
Latest Science on Sierran Forests
This file, which contains the exhibits for our major appeal of the Forest Service’s 2012 Giant Sequoia National Monument Management Plan, is the essence of the best available science on all areas of forest issues.  It includes the latest findings regarding fire, grazing, road, water, and species science in the Monument and is relevant to all Sierran forests.
April 11, 2013
Testimony of Dr. Dominik Kulakowski, Assistant Professor, Clark University before the Subcommittee on Public Lands and Environmental Regulation of the Committee on Natural Resources of the United States House of Representatives on the Depleting Risk from Insect Infestation, Soil Erosion, and Catastrophic Fire Act of 2013

Congressional testimony of Dominik Kulakowski emphasizes a number of major concepts that
1. Climate/weather, not fuels, is the driving force in most large fires.
2. There is no correlation between beetle kill and fires.
3. Green trees are more "hazardous" in terms of fire than beetle killed tree due to canopy and flammable resins. .
4. Emphasizing reducing flammability of homes rather than trying to treat (i.e. thin) forests is a far more economical and effective measure.

April 8, 2013
Black-backed Woodpeckers One Step Closer to Endangered Species Act Protection in California, Oregon, South Dakota
SAN FRANCISCO— The U.S. Fish and Wildlife Service announced today that it will conduct a full status review to determine whether genetically distinct populations of black-backed woodpeckers — which thrive in forests where fires have burned — will get protection under the Endangered Species Act in two regions, California/Oregon and the Black Hills of South Dakota. Today’s decision that protection may be warranted for these birds comes in response to a scientific petition submitted by four conservation groups last May. Black-backed woodpeckers are threatened by logging that destroys their post-fire habitat.
“This is the first time in the history of the Endangered Species Act that the government has initiated steps to protect a wildlife species that depends upon stands of fire-killed trees,” said Dr. Chad Hanson, an ecologist and black-backed woodpecker expert. “We are pleased to see the U.S. Fish and Wildlife Service recognize the naturalness and ecological importance of this post-fire habitat.”
Black-backed woodpeckers rely on what is known as “snag forest,” high-diversity habitat that’s extremely rare and ephemeral because it is only created when either fire or beetles kill the majority of trees in an area. These standing dead trees — called “snags” — then become a virtual bed and breakfast for black-backed woodpeckers by providing nesting space as well as large amounts of wood-boring beetle larvae for the woodpeckers to eat.
Post-disturbance forests are only livable for the species for a short time — roughly 7-10 years — which means the woodpeckers need newly burned or beetle-killed forests to continually appear on the landscape. Unfortunately, that habitat is often destroyed by post-disturbance logging that removes the very trees the birds rely on. Because of logging, suppression of the natural fire regime and large-scale forest “thinning” to prevent fires in backcountry areas, there is now an extremely limited amount of usable habitat available to black-backed woodpeckers.
“The black-backed woodpecker is so highly adapted to burned forests that it’s almost impossible to spot when perched on a fire-blackened tree,” said Duane Short, a zoologist with Biodiversity Conservation Alliance. “Its black back and wing feathers protect it from predators as it forages for beetles, some of which have themselves evolved in concert with burned forests.”
“These birds desperately need the lifeline of the Endangered Species Act,” said Justin Augustine with the Center for Biological Diversity. “There are likely only a few hundred pairs left in South Dakota’s Black Hills, and about a thousand pairs in Oregon and California — these birds could wink out of existence if we don’t stop razing their habitat as soon as it appears.”
With dangerously small populations of fewer than 1,000 pairs in Oregon/California and only about 400 pairs in the Black Hills, the birds depend on habitat that’s likewise extremely scarce: Just 2 percent of the forests within the woodpeckers’ range from the Cascades of Oregon through California’s Sierra Nevada are currently likely suitable for them to live in, and only about 5 percent of forests in the Black Hills are suitable. The great majority of this limited habitat is unprotected and therefore open to logging.
“Over my 22 years of field-checking proposed timber sales in eastern Oregon national forests, I have been privileged to observe black-backed woodpeckers but have increasingly noticed their scarcity as the Forest Service has been implementing ever larger timber sales aimed at artificially reducing natural fire and insect occurrence, as well as numerous post-fire logging projects eliminating black-backed woodpecker habitat,” said Karen Coulter of the Blue Mountains Biodiversity Project. “This status review is a good first step toward reversing that trend”
The groups that filed the petition to protect the birds were John Muir Project of Earth Island Institute, Center for Biological Diversity, Blue Mountains Biodiversity Project and Biodiversity Conservation Alliance.
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Fire Science

Sequoia ForestKeeper has a great respect for fire's ability to replenish the soil and clear out the dead brush and weak trees in the forest. But sometimes, fire gets too close to communities and destroys people's homes because they were not aware of what measures homeowners can take to protect their property from wildfire. Here, you will find the latest reports on what steps people whose property abuts the forest should take in order to protect their land and dwellings.

This page contains fire science information on community protection, fuels reduction in the general forest, and salvage logging.


"The Myth of "Catastrophic" Wildfire:  A New Ecological Paradigm of Forest Health" by Dr. Chad Hanson, Ph.D., Executive Director of John Muir Project, Winter 2010

This peer-reviewed white paper discusses some of the latest research on fire behavior and effects in the Sierra Nevada.  It begins:

In the summer of 2002, I came across two loggers felling fire-killed trees in the Star fire area of the Eldorado National Forest in the Sierra Nevada. They had to briefly pause their activities in order to let my friends and I pass by on the narrow dirt road, and in the interim we began a conversation. One of the loggers pointed further down the road to a forest stand in which the fire burned less intensely. Most of the trees were alive and green.
“I can see why people wouldn’t want us to cut down a stand like that,” he said, pointing to the green stand.
“But what does it matter if we cut down an area like this?” he asked, referring to the heavily-burned area where high-intensity fire had occurred. “All of the trees have been killed. It’s been destroyed. What sort of wildlife is going to live here?” he asked rhetorically.

I told the man that I didn’t know the answer, and that his was a question that deserved some investigation. That conversation, and the curiosity it piqued in me, ultimately led me to graduate school to earn my Ph.D. in ecology, with a research focus on fire ecology in forest ecosystems. I found the answers to my questions to be as startling and counter-intuitive as they were undeniable, and increasingly I have wondered at the tremendous gap between the rapidly mounting scientific evidence and the widely held popular notions about wildland fire in our forests.

Every fire season in the western United States, we see on television the predictable images of 100-foot flames spreading through tree crowns, while grim-faced news anchors report how many acres of forest were “destroyed” by the latest “catastrophic” fire. The reaction is understandable. For decades, countless Smokey the Bear advertisements have told us that forest fires are bad and damaging. Until about 25 years ago, land management agencies, such as the U.S. Forest Service, genuinely believed that they could essentially eliminate fire from our forests if they had enough resources to suppress fires – and they sought to do just that.  By the late 20th century, however, forestry officials began to concede that, historically, frequent low-intensity fires were natural in our forests, slowly creeping along the forest floor after lightning ignitions, reducing fuel on the forest floor and naturally thinning-out brush and small trees. Though a begrudging acceptance of the
benefits of low-intensity fire began to take hold, it was commonly assumed that areas of high-intensity fire, where tall flames killed most of the trees, were fundamentally the unnatural result of fuel accumulations from decades of fire suppression. Thus began the “catastrophic wildfire” paradigm, which divided fires into two categories: good fires and bad fires depending upon whether they burned at low-intensity or high-intensity, respectively.

A Forest Service public education brochure for the Sierra Nevada from 2004 captured the thinking underlying this paradigm. The brochure, entitled “Forests With A Future”, portrayed high-intensity fires as an “eco-disaster” that “destroy wildlife habitat.” No scientific studies were cited to support this characterization. Under the heading of “Good fires, bad fires”, the brochure opined: “Fire is natural to the forest. But not the kind of fire that burns so hot, and shoots up so high, it destroys everything.” The report blamed the perceived threat of high-intensity fire on a build-up of fuel from “fire suppression practices over the last century”. It proposed a massive logging program on national forests, under the guise of “thinning”, ostensibly to eliminate high-intensity fire from the landscape.


"Giant Sequoias Need Fire" by National Geographic, 2010

Giant sequoias, found in the U.S. Sierra Nevada, require heat from fire to regenerate. Now, sometimes humans intervene in Yosemite National Park to help the process.

This 20 minute video narrated by and starring Jack Cohen explains all of the various issues with fuels and ignitability of a structure.  Start at 8:57 in the video to fast forward to his discussion of home ignitability.    


The Open Forest Science Journal January 2008


Fuel treatments to reduce fire impacts have been promoted as a public forest restoration priority by policy [1] and the Healthy Forests Restoration Act of 2003. It is difficult to generalize about the effectiveness of fuel treatments under all conditions [2, 3], but treatments are not universally effective when fire affects treated areas [4]. Factors influencing effectiveness include forest type, fire weather [4], and treatment method [5].

However, treatments cannot reduce fire severity and consequent impacts, if fire does not affect treated areas while fuels are reduced. Fuels rebound after treatment, eventually negating treatment effects [3, 6]. Therefore, the necessary, but not sufficient, condition for fuel treatment effectiveness is that a fire affects a treated area while the fuels that contribute to high-severity fire have been reduced. Thus, fire occurrence within the window of effective fuel reduction exerts an overarching control on the probability of fuel treatment effectiveness. The probability of this confluence of events can be estimated from fire records. Although this probability has not been rigorously analyzed, it has often been assumed to be high [7].

The probability of future fire occurrence also abets assessing the ecological risks incurred if fuels are not treated. Therefore, analysis of the likelihood of fire is central to estimating likely risks, costs and benefits incurred with the treatment or non-treatment of fuels.

Assessing fire occurrence and its effect on fuel treatment effectiveness also has merit because treatments can incur ecological costs, including negative impacts on aquatic systems [8], soils [7], and invasion by non-native plants [9, 10]. Here, we use watershed and aquatic systems as a specific context for evaluating tradeoffs involved with treatment and non-treatment of fuels on western public lands. However, the analysis applies to upland ecosystems as well.

Click Here to read the entire study.


April 2005

This is the accessible text file for GAO report number GAO-05-627T entitled 'Wildland Fire Management: Progress and Future Challenges, Protecting Structures, and Improving Communications' which was released on April 26, 2005.

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Before the Subcommittee on Public Lands and Forests, Committee on Energy and Natural Resources, U.S. Senate:

United States Government Accountability Office:


For Release on Delivery Expected at 2:30 p.m. EDT:

Tuesday, April 26, 2005:

Wildland Fire Management:

Progress and Future Challenges, Protecting Structures, and Improving Communications:

Statement of Robin M. Nazzaro, Director, Natural Resources and Environment:


GAO Highlights:

Highlights of GAO-05-627T, a testimony before the Subcommittee on Public Lands and Forests, Committee on Energy and Natural Resources, U.S.Senate.

Why GAO Did This Study:

Wildland fires are increasingly threatening communities and ecosystems. In recent years, they have become more intense due to excess vegetation that has accumulated, partly as a result of past suppression efforts. The cost to suppress these fires is increasing and, as more people move into fire-prone areas near wildlands, the number of homes at risk is growing. During these wildland fires, effective communications among the public safety agencies responding from various areas is critical, but can be hampered by incompatible radio equipment.

This testimony discusses:

(1) progress made and future challenges to managing wildland fire, (2) measures to help protect structures, and (3) the role of technology in improving responder communications during fires. It is based on two GAO reports: Wildland Fire Management: Important Progress Has Been Made, but Challenges Remain to Completing a Cohesive Strategy (GAO-05-147, Jan. 14, 2005) and Technology Assessment: Protecting Structures and Improving Communications during Wildland Fires (GAO-05-380, Apr. 26, 2005).

What GAO Found:

Over the last 5 years, the Forest Service in the Department of Agriculture and land management agencies in the Department of the Interior, working with the Congress, have made important progress in responding to wildland fires. Most notably, the agencies have adopted various national strategy documents addressing the need to reduce wildland fire risks, established a priority to protect communities in the wildland-urban interface, and increased efforts and amounts of funding committed to addressing wildland fire problems. However, despite producing numerous planning and strategy documents, the agencies have yet to develop a cohesive strategy that identifies the long-term options and related funding needed to reduce excess vegetation that fuels fires in national forests and rangelands. Reducing these fuels lowers risks to communities and ecosystems and helps contain suppression costs. As GAO noted in 1999, such a strategy would help the agencies and the Congress to determine the most effective and affordable long-term approach for addressing wildland fire problems. Completing this strategy will require finishing several efforts now under way to improve a key wildland fire data and modeling system, local fire management planning, and a new system designed to identify the most cost-effective means for allocating fire management budget resources, each of which has its own challenges. Without completing these tasks, the agencies will have difficulty determining the extent and location of wildland fire threats, targeting and coordinating their efforts and resources, and resolving wildland fire problems in the most timely and cost-effective manner over the long term.

The two most effective measures for protecting structures from wildland fires are (1) creating and maintaining a buffer around a structure by eliminating or reducing trees, shrubs, and other flammable objects within an area from 30 to 100 feet around the structure and (2) using fire-resistant roofs and vents. Other technologies—such as fire- resistant building materials, chemical agents, and geographic information system mapping tools—can help in protecting structures and communities, but they play a secondary role. Many homeowners, however, are not using the protective measures because of the time or expense involved, competing values or concerns, misperceptions about wildland fires, or lack of awareness of their shared responsibility for home protection. Federal, state, and local governments and others are attempting to address this problem through a variety of educational, financial assistance, and regulatory efforts.

Technologies exist and others are being developed to address communications problems among emergency responders using different radio frequencies or equipment. However, technology alone cannot solve this problem. Effective adoption of these technologies requires planning and coordination among federal, state, and local agencies involved. The Department of Homeland Security, as well as several states and local jurisdictions, are pursuing initiatives to improve communications.

What GAO Recommends:

In its report, GAO recommended that the Departments of Agriculture and the Interior develop a plan for completing a cohesive strategy that identifies options and funding needed to address wildland fire problems. The departments agreed.

GAO Entire Report


Reducing the Wildland Fire Threat to Homes: Where and How Much?

Progress and Future Challenges, Protecting Structures, and Improving Communications

Fire Weather: US Forest Service Handbook for managing Fire