Drought, fires and beetles — California’s forests

With increasing heat and drought across the West, one of the largest tree die-offs in modern California history reached new heights last year and, in combination with wildfires, has left much of the state’s once sprawling green forests browned, blackened and in critically dire shape.

An estimated 9.5 million trees died from bugs, disease and dehydration in 2021, according to new aerial survey data from the U.S. Forest Service. The losses were slightly less than what was recorded in surveys two years earlier but still well above what scientists consider normal. The run of mortality since 2010 now exceeds 172 million trees.

The epidemic, which started last decade in the southern Sierra Nevada and has since spiraled throughout the state, is contributing to the changing character of California’s 33 million acres of forests. The timberland, notably conifer forest, has become increasingly prone to losing biodiversity, giving way to encroaching shrubs and grasslands, and burning up in wildfire.

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Already, dead pines and firs and have provided fodder for scores of fires, and in doing so, compounded the increase in tree mortality. Last year alone, a few hundred million trees may have died from flames in California, according to burn severity data from the Forest Service.

“Our forests are at mortal peril,” said Hugh Safford, a recently retired Forest Service regional ecologist and now chief scientist at Vibrant Planet, a company that works on climate issues. “They are absolutely at mortal peril.”

Beyond the harm done to the flora and fauna of the forest, the die-off threatens to blunt many of the benefits that these wildlands provide, such as supplying clean water, producing high-quality timber and absorbing carbon to help limit global warming.

“To me, the only question is if we can get our (act) together in time (to save the forest),” Safford said.

A leading cause of the die-off is the changing climate. Frequent drought over the past decade, much of it tied to warming temperatures, has not only created conditions ideal for fire, but also has weakened trees and made them more susceptible to insect infestation and disease.

The tens of millions of dead trees counted in the Forest Service surveys, which do not include burned trees, are often deprived of water to the point where they can no longer survive adversity, the main foe being bark beetles.

Making matters worse, scientists say, is the overcrowding of California’s forests. A century-old policy of fighting wildfires, instead of allowing them to burn, has thwarted a natural process of forest thinning. The subsequent build-up of vegetation has created both a dangerous amount of tinder for fire and a situation detrimental to the health of the trees.

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“The forest is in such a high density and is facilitating mortality because the trees can’t live when they’re competing with their neighbors,” said Scott Stephens, a professor of fire science and ecologist at UC Berkeley. “They’re just not able to weather episodes of difficulty anymore.”

Last year, in the southern and central Sierra and as far north as Lake Tahoe where lifeless trees blanket mountainsides in deathly apricot hues, the epidemic continued, with significant losses in Fresno and Tulare counties, according to the Forest Service survey data.

The most concerning toll, though, was even farther north, where dead trees — hard to find just a few years ago in the much moister terrain — now pepper the slopes of the Klamath, Trinity and northern Sierra ranges. Siskiyou County recorded the most deaths of any county in 2021, with about 10% of the total.

“The Northern California forests have not had the episodes of mortality that we’ve seen in the south, but if we have continued drought in the north, we’re going to see the same, which is very worrisome,” Stephens said.

Nearly two-thirds of the trees that died in 2021 were firs, often infested with fir engraver beetles, according to the survey data. Sugar and ponderosa pine, early victims of the die-off, also continued to perish, largely because of mountain and western pine beetles.

In the East Bay, an unusual routing of 75,000 hardwood trees was recorded last year, which included acacia and eucalyptus. Scientists studying the deaths believe it may be the work of fungi in tandem with drought. Mortality is extensive at the East Bay Regional Park District’s Anthony Chabot, Reinhardt Redwood and Tilden parks.

Dead trees that pose a dangerous wildfire risk as part of a mass die-off dot the landscape in East Bay Regional Park District land in Contra Costa County.
Dead trees that pose a dangerous wildfire risk as part of a mass die-off dot the landscape in East Bay Regional Park District land in Contra Costa County.
Provided by East Bay Regional Park District
The surveys are designed to broadly assess forest conditions on federal, state and private lands in California. They’re conducted annually by planes crisscrossing the state, though a full count of dead trees was not completed in 2020 because of the coronavirus pandemic.

The surveys show that increased tree mortality began at the start of the last decade and peaked at the end of the five-year drought. In 2016, 62 million trees died.

The numbers have since fallen, but they’ve remained much higher than the 1 million annual deaths from age considered typical. If the current year continues to see little precipitation, after two previous dry years, scientists say the pace of loss will inevitably pick up again.

“We’re always hoping for the fabulous February (rain) and the March miracle,” said Sheri Smith, regional entomologist for the Forest Service and one of the managers of the aerial surveys. “But if it ends up dry again, I have no doubt we’ll start to see an increase in tree mortality.”

The drought-driven die-off, observed across 1.3 million acres last year, comes on top of — and is partly responsible for — the havoc that wildfire wreaked on trees in 2021.

While there is no official tally of dead trees across the 2.6 million acres that burned in California, the Forest Service estimates that more than 100 million trees died in the northern Sierra’s Dixie Fire alone. The 963,000-acre blaze may be the most destructive, in terms of trees killed, in California in decades.

“The loss from that fire dwarfs any insect and disease mortality over the past couple of years,” said George Gentry, senior vice president of the California Forestry Association, which represents the timber industry.

Logging companies, as a matter of course, regularly deal with variability and less-than-stellar forest conditions, often removing trees to halt pathogens or harvesting trees before they’re toppled by bark beetles. Gentry, however, says there’s not much that can be done when timberland is completely burned over.

While fire has historically benefited California’s wildlands, helping clear overgrowth and reinvigorate landscapes, many of the recent blazes, like the Dixie Fire, have burned hotter than in the past, making them more destructive than restorative.

Manual tree thinning and intentionally lighting fires to bring back more sustainable conditions remain among the most effective strategies, though such work has been sparse given the scope of the problem.

In January, in what the federal government called a “paradigm shift” to lessen wildfire risk, the Forest Service unveiled plans to spend an additional $655 million in each of the next five years on forestry projects, on top of the roughly quarter million dollars it currently spends annually. California is expected to receive a major chunk of the windfall.

Gov. Gavin Newsom, at the same time, has boosted state spending on fire prevention, recently proposing a $1.2 billion two-year wildfire package that includes $482 million to reduce the buildup of vegetation.

The two governments have agreed to jointly treat 1 million acres of forest in California each year by 2025.

“I’m mildly optimistic for the first time in my career,” said Malcolm North, a research ecologist with the Forest Service and professor of plant sciences at UC Davis, who has long advocated for more tree removal and prescribed burning.

North, however, said that while commitments from state and federal authorities will help lessen fire danger, at least somewhat, more work will be needed to help forests withstand forces of drought, disease and insect infestation.

“Wildfire is not the only problem we’re facing,” he said. “If you want to make the forests able to survive these other stressors with climate change, you really have to reduce competition among the trees.”

A new scientific paper authored by North, with help from several others including Stephens at UC Berkeley, calls for removing as much as 80% of the trees in parts of California’s forests. The seemingly hawkish target, outlined in the journal Forest Ecology and Management, is based on the premise that this is how much vegetation needs to be cleared to give trees the space they need to grow strong and resilient.

The research cites timber surveys from 1911, before modern forestry and wildfire suppression, that found forests were six to seven times less dense than they were a century later, with trees twice as big.

The study’s recommendations, though, have not been universally welcomed. Some suggest that the level of clearing proposed is excessive and would result in widespread disturbance to forests, notably wildlife, as well as unleash damaging amounts of carbon from trees into the atmosphere.

Chad Hanson, a research ecologist and co-founder of the nonprofit John Muir Project who is skeptical of forest interventions, downplays the severity of the tree die-off. He says big swaths of mortality in the Sierra provide unique habitat for birds, insects and other animals and have long been part of the natural process.

“It’s good to have a mix of live trees and dead trees,” Hanson said. “It’s about where that mix is.”

Most researchers, though, believe the equilibrium of the forest is wildly off. North and others, noting that current forest management policies aren’t working, insist big changes are needed to protect California’s wildlands, both for their intrinsic value and their value to people.

“There’s a whole suite of ecosystem services associated with forests,” North said. “It’s really important to hold on to those.”


In spite of ever increasing drought conditions, some scientists insist we must burn our way to more healthy forests. This is insanity. The Carr, Camp, Dixie and Caldor should have taught us we can no more manage wildfire during a drought than we can manage a hurricane. There is need for Prescribed Fire, but no room in the tool box for managed fire.


The key factor to keep in mind with those 4 fires is that they were never “managed” fires nor did they fit the criteria for a monitor and manage fire. They were always in full suppression mode by the controlling agencies. The Tamarack Fire would however, be a better example of the hazards of a managed fire in today’s world. The issue becomes however in absolutes. In the case of the Tamarack, it fit the managed fire parameters and the FS guidelines mandated that it be such. The world of absolutes does not allow the right right people with the right experience to make the right calls. Rather it is either Managed or on the side of the spectrum, a fire can never be managed with a whole lot of room in the middle. The Tamarack could have been Managed with the right set of boundaries established, which would be long before it was racing toward Markeeville. Another factor to consider is whether the FS itself has the capability to adapt to a changing environment quickly enough to not be in world of absolutes. That is really where I personally see the issue. There are many factors that are hindering the FS from becoming more adaptively capable, refer to the entire thread on FS pay for one of the most significant. So, unfortunately it does come down to an absolute stance and that for me would be no managed fires allowed. That absolute will continue to have highly destructive consequences until such time as the FS demonstrates it can be a more adaptively capable agency


I cited those fires as examples of extreme fire behavior caused by drought stressed fuels, not as examples of managed fire.

In spite of Randy Moore’s letter last summer that all fires would be full suppression, The tactics on the Mc Cash, the Monument and the River complex would demonstrate that word is loosely interpreted by some fire teams.

The backfires on the Dixie fire are also in question. At the recent Sierra Cascade Logging Conference it was stated that 60% of the 950,000 acres burned on Dixie were the result of backfires. Indirect attack is full suppression, but ill advised backfires are a different story.

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60% of Dixie caused by backfires… source?

The use of the term backfire seems very inaccurate since that is a seldom used tactic. Usually firing out is used to create black and improve/widen existing line - defensive. Backfiring is an offensive term.

On every piece of line I was involved in constructing was overrun by advancing fire front throwing embers 1/2 mile or more and crown runs that carried fire through canopies across line.


The statement that 60% of the Dixie fire was burned in backfires was made by the moderator of the panel discussion on Fire and the Furure of California Timberlands at the 2022 Sierra Cascade Logging conference in Redding. This was a 3 hour panel discussion CalFire Chief George Morris and USFS Chief Tony Scardina were also on the panel and neither disputed those facts.

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Knowing both of the chief’s mentioned… they would have no clue of the amount of land burned during firing operations.
I am pretty sure that it would be just about impossible to determine that. The other option would be to put in lines and “hope” the fire stopped there once it hit the lines.
There has been a narrative supported by the timber industry that we ( the fire service) do not care about their timber and that we only care about private homes.
This is perpetuated by timber industry personnel and by retired fire service personnel who are now on their payroll and who support that narrative.
The timber companies need to do more to protect their assets. Why do we treat those private holdings different than a home or improvement. If you have not done your due diligence we move on and deploy our resources to assets where people have taken the time and put in the effort to prepare them. We have struggled with the timber companies and their opinion on when and how we should conduct firing operations where their lands are near populated areas.
There are some environmental restrictions on the timber companies with regard to land clearing and fuel breaks… but plowing red slash into a cut block does not make it easy to hold a fire…
I agree with the previous statements that large scale landscape burns are not necessarily a plausible solution to the situation. There are many who support this false narrative and in my opinion border on negligence with their comments.
You can suggest that type of solution to this problem in a state with 41 million people, a fragile ecosystem which is under attack from prolonged drought and a changing climate.
It is a part of the solution, but not the entire solution.


The tactics on those fires are the tactics of the future - and show the type of flexibility and adaptability from USFS fire managers that others on this thread are disputing exist, ironically. Some of the best work we did all year to manage the landscape occurred on those fires; low intensity UAS firing at night and under smoke inversions, as well as judicious hand lighting. Other parts of those fires looked like all the rest across the state, expect at least something good came with the bad.

The Tamarack fire was in a location that any professional firefighter would look at and prioritize low for suppression when other fires were more pressing and closer to values. Look at the report that is circulating before you disagree. As for the timber companies, honestly after the last few years of their relentless insistence for illogical and dangerous tactics to be employed, I can’t even take them seriously anymore.

It is just continued arrogance to think that suppressing fires is the proper course of action, always, and that managing them is irresponsible, when both have outcomes that are highly unpredictable from the onset - and both, if they work out as intended, result in desirable outcomes. Always a big if. Remember that crystal ball we all joke about lacking? Do you really not see that all the worst fires of the year were ‘full suppression’ from IA - which changes nothing other than the political cover it gives the decision makers to hide behind - and the fire doesn’t care about our labels at any rate.

So, more of the same then? That seems to be working.


I am not sure arrogance is the right word… it seems misplaced.
Are you suggesting you just give up and not have any aggressive type of strategy? I guess those decisions are a matter of perspective. If you happen to own the values at risk in front of one of these fires, then I guess you would not be happy to hear that people are managing it.
Is there a point if we adopt that mindset where the public asks… what do we have them for? What do we pay them to do?
The key is working to not allow the fires to get to that point… thereby limiting the destruction. If you are going to allow a fire to burn freely with few sideboards, then you have just written off the impacts on the surrounding communities.
In my opinion… that is more arrogant than trying…

The arrogance arises from the notion that we really have the control one way or the other. It’s what got us here in the first place.


That opinion is not connected to any sort of reality. We will never control mother nature… but we can and should protect our resources… natural and human created.
Without that concept… there would be nothing to be a division of…

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That legislation did not come out of thin air. Ask the people of Berry Creek, or the homeowners in Forest Glenn or Coffee Creek if they think the USFS fire Management policy is benefitting them. Big Box fire management, landscape sized firing ops and burning private inholdings are not the cure.
We are in the worst drought in 1200 years. Now is not the time to try to manage fire.

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It will never be the time if we wait for zero risk. Thus, we continue down the well worn path of ineffectiveness and universal frustration - all while we watch watershed after watershed and community after community become incinerated. The complete suppression doctrine has proven its limitations. We’ve witnessed what lies below the end of the rope. We know what it sounds like to say to the people - “there is no one left to send.” We can’t ignore it any longer. Be among those who are trying to find a different way; else move off the line while those who are trying to carry the water bump pass.


America is a big country. Have you ever flown over the Frank Church Wilderness? 3,750 square miles of fire-adapted, deep canyon country. There’s no way to put out every fire there, especially when we have big lightning busts. California has NOT had very many fires that were managed for resource benefit in past 30 years strictly as a matter of policy - fires in California get managed because of resource drawdown. But fire use has been an important tool for land managers in Idaho, Montana, Colorado, Alaska, and in the Southwest, in places that aren’t as popluated as California. Taking that tool away makes no sense, and it isn’t even possible.

As for Berry Creek and big boxes, nothing about declaring a new 10am policy is going to change the facts on the ground. The fire that eventually took out Berry Creek was ‘managed’ because we had hundreds of other fires to IA in Northern California in August 2020, threatening places like Paradise, Santa Cruz, Vacaville, and the Wine Country, and it was triaged as low priority for initial attack. By the end of August we had a million acre fire burning across the Mendocino NF, the Sheep Fire was threatening Susanville, and the LNU, CZU, and SCU Complexes were burning across hundreds of thousands of acres surrounding some of the most affluent and populated parts of the state. And the Bear Fire was well-established in some of the steepest ground in the Northern Sierra, ready to get blasted out of there by September’s east winds.

To bring it back to the theme of this thread - drought, fire, and beetles: Things aren’t getting better any time soon for California, and the USFS (whose staff are still reeling from watching things like the Bear Fire go down) was unlikely to let any fires they had an opportunity to catch on IA burn just about anywhere in California, anyway. McClintock and LaMalfa are just posturing, and throwing gas on the fire.


these types of things very dangerous for us

That opinion is not connected to any sort of reality. We will never control mother nature… but we can and should protect our resources… natural and human created.

What a great time for rain in the west. Hopefully, lots of transpiration will occur as the brush and trees come out of dormancy. Maybe this will be another summer of the constant 3000’ marine layer along the coast. Let’s hope!!!