You probably believe that a significant part of the wildfire problem is too much fire suppression in past decades, so part of your reaction to news about recent wildfires may be “it’s just nature playing catch-up”, “environmentalists caused this” or “this will be good for the forest in the long run”.
But this conventional wisdom is wrong. The original proponents misconstrued the historical record and drew the wrong conclusions. Then they adopted those conclusions as dogma, ignoring the actual reasons. As a result of these errors we still pursue dangerous policies that often act against the interests of species we need to save. Please follow the explanation below, and I hope you will change your mind.
Two Views of Forests
A National Park ranger recently told me that “the forest service manages tree farms” while the park service “manages forests”. What he means is because the USFS makes billions of dollars per year selling timber to companies like Sierra Pacific, who aggressively harvest public timber both before and after forest fires, they manage their forests with careful consideration given to their customers. The park service is more concerned with managing wildlife, wilderness and forests for future generations.
So for example, a National Forest might manage a forest to concentrate on one species of tree, evenly spaced, crowns not touching, without underbrush, much like a tree farm. The park service might manage an old-growth forest with several types of tall trees creating a full canopy, a number of different shorter shade tolerant trees growing below, and a large variety of plants and habitats.
Both managed forests have features that reduce fires. The tree farm has less ‘kindling’ or underbrush and spacing slows spread. The old-growth forest also has less ‘kindling’ or underbrush and has lower temperatures at ground level, both due to shade. The tree farm needs regular maintenance, as it encourages fast growing conifers to grow in the gaps. The old-growth forest requires little maintenance, and can slowly change its tree mix to adapt to new conditions. The most dangerous type of forest for fire is one that was logged, has regrowth densely with pine trees and has not been managed for decades.
Promoting Forest Fires to Prevent Forest Fires
Forestry experts have long known that natural fires, such as lightning strike fires, are beneficial to some species and detrimental to others. For example, Pitch Pines are highly adapted to benefit from fire. Their sap, which was used to make turpentine, burns very hot, and they grow much faster than hardwoods. So these trees literally burn out their competition, quickly replace them, and have become dominant in New Jersey’s Pine Barrens.
From the 1940s to the 1990s, the amount and value of timber harvests from public lands increased significantly, and at the same time, the ‘tree farm’ model for managing forests slowly became the standard for most forests. Especially in the west, where the largest forests grow, academic literature shifted noticeably from a focus on forest biology to a focus on ‘commercially valuable timber’.
In the 1970s, Bruce Kilgore, a park service expert focusing on the Sequoia forest, wrote a series of influential papers prescribing more fires. Many of the largest trees in the forest, including the Giant Sequoia and the Douglas Fir either require or benefit from fire to reproduce and gain dominance. He argued that the ‘poor state’ of the forest was due to insufficient fire, and, as an associate director for the western park region, he designed and implemented various controlled burns throughout western parks to clear out the space between trees. He believed that returning to Native American burn practices would improve the forest.
Researchers in Kilgore’s region, especially from Sequoia National Park, apparently believed the public was wrong about forest fires and needed to be educated to appreciate them. They also promoted prescribed burns and did more research to reinforce the message. Critical articles about ‘fire suppression’ were written, and Research evolved to explain that old opposition to forest fires was why new wildfires were so severe. They visited many of the forests and forested national parks in the west to spread the theory. This approach smoldered along for years and finally spread like wildfire.
The Chart ‘Proving’ the Theory
One influential argument is illustrated in this slide created in 2016 to explain why the 1992 Rainbow Falls Fire had burned 82% of Devils Postpile and to recommend more burns. The chart shows that beginning in the 1700s until 1875, fires were common. Then they stopped for over 100 years. The accompanying presentation labels the normal fire period as ‘pre-Euroamerican’ and the no fire period as ‘fire exclusion’.
The chart is clear and simple. The presentation exclusively focuses on ‘fuel loads’ and ‘decaying over-story’ (falling branches & pine needles) as causing the conditions for the 1992 fire. Once commonplace fires were foolishly suppressed for too long, creating the unprecedented forest fire problem. There is only one solution: more prescribed burning. And the implication is ‘if only forest managers had listened to us sooner, today’s terrible wildfires could have been prevented’. Park forestry experts were trained with, helped produce various versions of this chart and uniformly repeat the points ad nauseum to visitors like me.
So What’s Wrong With The Chart?
I studied ecosystems in my youth, have visited over 350 national parks in the past 18 months, and my career involved creative, logical & statistical analyses often using a baseline to show cause and effect. I know this chart is bunk.
Why is there no mention of rising temperatures, decreased snowpack, the 1986-1992 California drought, unusually hot and dry Santa Ana winds, bug kill, climate change or the carbon pollution that causes all of those symptoms? The timeline bothers me too. Didn’t Cabrillo sail into San Diego Bay in 1542? And wasn’t Smokey the Bear big in the 1970s, not the 1870s? No, the explanation clearly does not fit the dates.
Natives Are Not Ents with Rakes
The primary error is in defining the ‘pre-Euro American’ baseline. Shoshone, Paiute and O’odham for centuries traded California shells along the precursors of the Santa Fe trail and other routes east. Before the Spanish built their first mission in California in 1769, Native Americans had already been trading furs with Europeans for 200 years. Native Americans in California were hunting for furs to trade with both the Spanish and others along the Santa Fe trail before the chart begins. Wars were fought in the 1600s over fur. Instead of being ’pre Euro American’, the baseline largely corresponds with peak Euro-American demand for hats, rugs, coats and anything that could be made out of fur.
Native Americans may love nature, but they’re human. Their favorite hunting technique was to start a fire, create a clearing, wait for the fresh grass to grow and then kill animals that came to graze. Some dangerous animals were cornered on mountaintops, in trees or in canyons by fire. The Blackfeet got their name from running through fields they burnt while herding bison herds over 50’ cliffs. And the natives would smoke the meat, cook some and even use fire to burn out the bases of large trees, including Sequoias, to camp in. In return for furs, native traded for guns, cloth and much more.
Native Americans are not magical tree shepherds that talk to trees and protect them; those are Ents. Natives didn’t start fires to help trees by ‘raking the forest’. Native Americans caused the extinction of Wooly Mammoths and many other large animals in North America. When given incentives to hunt for furs, they temporarily emptied the forests of many common species, using fire aggressively while living in the Sequoia forest. So following either their prehistoric practices or their behaviors when paid by ‘Euro-Americans’ is no guarantee of good stewardship of nature.
Bad Data Equals Bad Results
More basically, forests in North America did not evolve with man-made fire. Accidental fires were introduced 20,000 years ago by natives, and then intentional fires. ‘Euro American’ settlers also used fire to clear ranch land and remove brush. Categorizing natives separately from ‘Euro Americans’ even though they both used fire similarly is worse than bad science: it’s racist.
The tree rings of a single Giant Sequoia may go back 100 human generations, but they still only record the life of that one tree. Determining what is natural and healthy for any species requires looking at the biology the species evolved, not just looking at recently deceased samples. This mistake would be like finding micro-plastics in living humans and assuming that we evolved to need micro-plastics in our diet. Sequoia trees evolved 200 million years ago with dinosaurs: ten thousand times older than man-made fire on this continent. So the scale of this mistake is massive.
Any baseline for natural fire must either be set before humans introduced fire or it must exclude any man-made fires from the record, otherwise it will not match the conditions in which healthy forests evolved and thrived. Bad data equals bad results. But the researchers focused on where they had fire data, from tree rings, and not on the evolutionary biology of trees.
The Second Error
Having completely mistaken the baseline, the next error is how ‘fire suppression’ or ‘fire exclusion’ is explained.
The forest service has reprinted supporting material describing the heroic efforts of the Civilian Conservation Corps (CCC) to fight forest fires along with continued Smokey the Bear campaigns. So most people conclude that that ‘fire suppression’ is what caused the low fire period. But this revisionist history doesn’t match the chart. The CCC started in the 1930s and Smokey in the 1950s, but the fires stopped in 1875. Why?
Kilgore explicitly meant logging when he wrote “fire suppression”. Others used a broader term that included forests surrounded by logging as suffering from “fire exclusion”. But instead of using the unpopular term ‘logging’ to describe what caused the 100 year lull in forest fires, they both chose phrases that misled the public.
And logging fits the timeframe. In the late 1800s steam-powered sawmills and railways increased logging exponentially. That massive, concentrated logging was what prompted folks like John Muir to found the Sierra Club in 1892 and ladies in long white dresses to gather around the few remaining old Giant Sequoias singing hymns.
Also, prescribed burns are a type of fire suppression that reduces fuel loads and temporarily prevents fire. So, logically, the ‘fire exclusion’ argument is nonsense.
‘The man-made fires before 1875 were natural. Ignore when logging removed the forest. Letting the forest regrow was unnatural.
Fire suppression is unnatural and causes fires. So let’s use prescribed burns to suppress fire, and let’s not discuss what else causes fires.
That way, in the near future, we won’t have any more fires, and people can return to fur hunting for hats.’
— my restatement of ‘prescribed burn logic’
Kilgore’s prescribed burn approach is also a short-sighted and unnatural short-cut to achieve a healthy forest. It reduces loads and slows wildfire spread, but it achieves that at the expense of species diversity and quantities.
Promoting fires as the sole solution to managing forests can be the wrong solution for different types of forests in different areas. A month ago, I was in Tennessee mountain forests that had naturally changed from pine to hardwood over the past few decades. Climate change brought bugs that killed the pines, but the other species took over and now the forest is stable again. A policy of prescribed burns would have repeatedly regrown pines only.
Prescribed burns are also dangerous. Last week the forest service officially admitted causing the 45,000 acre Cerro Pelado Fire in New Mexico last year by initiating a prescribed burn.
And, obviously, burning a forest releases significant amounts of carbon into the atmosphere, contributing to the Climate Crisis, resulting in more forest fires. That’s counter-productive.
Still Haven’t Changed Your Mind?
Perhaps you still believe that forests need to burst into flames naturally whenever they fill with trees. Maybe you think that lightning strikes naturally cause forest fires that were suppressed for too long. Or you may think that prescribed burns simply work and are the best tool we have to fight fire.
OK. I’ve had these arguments before. Please, read on.
Forests Long Maintain Equilibrium Without Fire
Last week I drove through National Forests in Oregon and saw lots of ‘tree farms’. A good example of a prescribed burn forest in a national park unit is around Devils Tower in Wyoming. Superficially, it looks a little like an old-growth forest, with mature dominant trees spread out and very little undergrowth between. The deer love the tender new shoots. But it also looks like a tree farm. There is far less species diversity than an old growth forest. The frequent fires make the forest inhospitable to other species.
I’ve hiked through dozens of old-growth forests in the past year and many more in every forested continent in the world over my life, and they simply feel completely different. The basic reason there is space between the trees is that the largest tree canopies block light from reaching the forest floor, but the deeper difference is found in the rich diversity of life under that canopy. Consider the Pitch Pines again. After they benefit from wildfire, they grow to maturity in 25 years, covering the floor with needles to prevent competition. Then each tree can live in that stable environment for up to 200 years, so another fire may not be required for well over 100 years. Rare orchids and other species evolved to live in the long stable period between fires.
The mixed Sequoia forest has much older trees, like Douglas Fir and the Giant Sequoia with lifespans from 1000 to 3000 years. After they take advantage of fire and grow to maturity, the forest can remain stable for centuries if not millennia without the trees needing another fire. In the relative darkness under their canopies, shade tolerant trees, low-light flowers, shrubs, specialized insects, mushrooms and mosses have evolved. These ecosystems did not develop in an environment of frequent fires. Forests naturally evolved to achieve equilibrium in their density, without needing humans to periodically burn out their underbrush.
And most types of trees did not evolve to require fire to reproduce or to have frequent fires. Even the Coastal Redwood does not need fire. Sure, it can survive a rare fire over its 2,000 year lifespan and may benefit from space cleared for the next generation. But it can also just fall down, clearing a huge space and letting the next generation grow all along its fallen trunk. Many forests grow in wetlands, swamps, along the foggy coasts, in floodplains, and along glacial creeks, in cool, wet environments often with little fire for centuries.
Most of us have never seen how massive trees can grow if left alone for centuries. I have seen centuries old Cottonwoods, Loblolly Pines and Live Oak trees in their own forests, and their tree rings do not show frequent fire. They do best when unmolested by humans. So, contrary to the myth promulgated by this study, forests do not need to burst into flames naturally whenever they fill with trees.
But Lightning Strikes Cause Fires!
It can be difficult to estimate how often wildfires should occur naturally, but isolated Santa Cruz Island provides some helpful data. In the past 150 years, there have been 15 fires and only one was caused by lightning. The rest were caused by humans. So, even in a protected natural area with few people, conservatively humans can accidentally cause over ten times as many fires as lightning.
Lightning strikes are more common in the High Sierras, but they also often occur during storms, when it’s raining. Many times in thunderstorms, lightning only burns one tree. Yosemite National Park also kept fire records for 150 years, and most early lightning strike fires were small, typically 100 or sometimes 1000 acres. Humans more often play with fire in dry conditions, when it is not raining.
Also, the Climate Crisis is increasing lightning strikes. I was driving through the area during the massive array of lightning that set off the 88,000 acre KNP Complex Fire in September 2021 along with other fires across California. It was dry, and I’ve never seen so many separate lightning strikes for so long across such an huge area. It looked apocalyptic. Again, the presence of humans and our bad behaviors confounds our analysis of natural fire conditions.
But Fires Were Suppressed!
Even so, some of you are going to comment that the CCC built watch towers, reported wildfires and sent in crews to fight fires. You remember seeing helicopters drop water on fires on TV. Before you write that comment that you won’t be able to delete, consider the following questions.
Did the CCC Cause More Forest Fires Than They Stopped?
The CCC built roads and campgrounds encouraging millions of careless visitors deep into the forest to park their cars on the dry grass, smoke cigarettes and make s’mores around campfires left burning all night. The CCC also emptied flood plains to make room for new housing developments. They created dams which diverted rivers and streams to irrigation, bringing millions more into cities that also used river water for swimming pools, golf courses, landscaping and public water fountains, lowering natural water levels. So they both enabled more accidental fires and increased the flammability of natural forests.
Yes, they fought fires too, and I’m sure your great grandpa was very brave. But they didn’t have helicopters, fire retardant or those tanker planes that scoop up water from lakes. They had mules to carry gear into the forest, axes and shovels. It would take days to get into the wilderness, so most of their fire fighting was done near where people lived and camped. Actually, that’s where wildfire fighting has always focused, including today. Which raises the next question.
Why Are The Wilderness Forests Burning Too?
All the various fire suppression efforts focused primarily on human adjacent forests and let wilderness fires burn out naturally. So the wilderness forests should not have been affected by the CCC, Smokey the Bear or even modern fire fighting. But the wilderness forests are burning too. Alaska, Siberia, and northern Canada all have had devastating wildfires, despite little or no history of effective fire suppression. If the ‘fire suppression’ meant what people think and was true, then those wilderness forests would have fewer fires.
I’ve visited all 10 of the most forested national parks in California in the past 18 months, and with few exceptions, they’re all badly burnt. In fact, one of the parks is mostly desert with only cacti, and its “trees” still burned. And in the parks that had both developed and wilderness forests, the wilderness areas burned worse. [I’m posting before I have published most visits on my own blog, because this is urgent.]
- Devils Postpile: Rainbow Fire 1992, burned 82% of the monument, much of it severely
- Lassen Volcanic Park: 2021, the 1 million acre Dixie Fire burned 70% of park, mostly wilderness
- Lava Beds: 2000, the 85,000 acre Caldwell Fire burned 2/3 of the park
- Mojave: 2020, Dome Fire 40k+ acres killed 1.3 million Joshua Trees.
- Muir Woods: Small, coastal grove in a wealthy suburb, no fire.
- Pinnacles: 2021 Pinnacles Fire contained quickly
- Redwood: Canoe Fire 2003, relatively small, cool coastal climate.
- Santa Monica Mountains: Coastal, 2018 Woolsey Fire, burned 88% of the park
- Sequoia/ Kings Canyon National Parks: 6 fires in 6 years, burning more than 85% of Giant Sequoia groves, killing ~12k large GS, a significant percentage of those remaining in the world
- Whiskeytown (photo): 230,000 acre Carr Fire in 2018, 97% damage
- Yosemite National Park: 250,000+ acre Rim Fire burned over 10% of the park
Many of the worst burns happened in parks that used prescribed burns extensively for decades, including Lassen and Whiskeytown. Their park newsletters describe those efforts in detail, even though they obviously didn’t make any difference. But they don’t mention climate change at all.
So Do Prescribed Burns Do Anything?
Not as far as I can see. I’ve driven through areas burned recently that were both treated with prescribed burns and not, and there’s zero difference. Tree kill is extremely high in both cases. Even the soil has been sterilized in some areas, meaning that trees won’t be able to grow there until new microbes develop. There’s no significant difference in burns between parks that had long-standing ‘prescribed burn’ policies and those that prevented fires for decades.
Driving back and forth this summer between the cool Pacific coast and hot inland areas made it crystal clear that the cause of all the unusual wildfires is higher temperatures alone. The math supports this as well, as more predicted fires are directly correlated to temperature rise. Fuel loads and prescribed burns are rounding errors compared to global warming. Instead of discussing ‘fire suppression’, we should have been discussing ‘carbon reduction’.
Kilgore never imagined today’s Giga-fires. His prescribed burns were small affairs of a few thousand acres total over many years. Studies of historical fires in Yosemite are also very small, a couple hundred or maybe a thousand acres in a year. Today fires reach a million acres at a time, and the same forests burn repeatedly. And of course, larger more frequent burns mean more carbon pollution in the air, increasing global temperatures.
I spoke with fire brigade officials during my own wildfire evacuation, and they will explain how they want to “reduce loads” near people’s homes. And I know that one reason is to save the lives of their crews pictured above. But that doesn’t mean that our forest management policies should be determined by the timber industry profits, the convenience of a few remote homeowners, insurance companies and budgetary constraints. We need a wholistic policy to decide what’s best in the long run.
Missed Opportunities To Tell the Truth
To his credit, the Superintendent of Sequoia/Kings Canyon has clarified that actually their recent fires are due, at least in part, to the Climate Crisis. But the damage has been done by those earlier studies, from old growth forests being clear cut, to false hope being given, and to accidental wildfires going out of control from poorly “controlled burns”. And the staff is still contributing to misinformation.
Blaming environmentalists and the Interior Department for causing forest fires is common among right wing politicians. Sequoia park is in Kevin McCarthy’s district. Tr*mp once said some nonsense about ‘raking forests’. I expect that sort of thing, but the lies widely repeated have consequences.
Part of our collective Climate Crisis trauma is being told that what’s obviously happening, isn’t really happening. I’m angry that our tax dollars are still being used to tell people that all we need is more fire and that they’re not being used to tell people about carbon pollution.
Most parks do not have Climate Change park brochures, but a few do. I just picked a new one up, and it discusses how the climate changes over time and how recently there have been some unusual events. But the brochure never uses the word “carbon”. I have never heard a park ranger or exhibit or publication suggest ways visitors can reduce their carbon footprint.
Instead of facing the actual problem, I’ve read many congratulatory pieces on how “prescribed burns” helped limit the damage in areas where it clearly didn’t help at all. I’ve read persuasive pieces on how “controlled burns” reduced fire danger in forests that have had wildfires annually in the same places. I even read an article last week describing how wildfires provide ‘a reset opportunity’ for animals, despite many of them burning to death horribly.
I’m sick of reading about how the problem is “weather, unusual beetle activity, El Niño, droughts, unusual precipitation patterns, and extreme temperature events”. Why can’t they admit that all of those are symptoms of the Climate Crisis caused by people burning carbon? And everywhere, our taxpayer-paid uniformed rangers talk about how Native Americans used fire to keep the forests healthy.
Once or twice I’ve heard a ranger talk that hints at the real problem by asking folks leading questions obviously hoping someone like me will raise the issue, but so far, the Interior Department is not using this opportunity to tell the truth to visitors who might be willing to change their behaviors. I find it appalling to see giant gas-guzzling RVs and trucks still driving through wildfire devastation, since they contributed to it and still are contributing to the problem. We pay these park employees to tell the truth, not to misinform the public.
John Muir, Teddy Roosevelt and others didn’t save the forests “forever” only to have them be burned by carbon pollution and inaction. We owe it to future generations of all species to try harder than that.
What We Should Be Talking About
Forest management should be based on promoting species diversity and quantities, not timber sales. This is especially important when most species on earth are threatened by the Climate Crisis. Fire policies should be designed to reduce carbon pollution and keep carbon on the ground.
Yes, we need to plant more trees. But we also need to decide what we’re going to do with them. Are we going to plant them just to burn them?
Fire is not the only way to fight fire. Dead or crowded trees can be cut down and left in piles, something you now see in some national parks. Wetlands can be restored. Carbon can be reduced.
We need to reserve more space for new forests and more wildlife corridors and bridges. Many species displaced by wildfires have nowhere else to go. Letting a critical old-growth forest burn is like deciding that the last rhino reserves need to be burned, so that a timber company can sell stylish burned wood.
We need to be talking about water use. Farmers see a river and think that all the water can be diverted for agriculture. Ranchers want the river diverted for livestock. Developers want the water diverted for real estate, swimming pools, fountains and green lawns. People want the water for drinking, floating and for jet skis. So the demands on natural water are not only oversubscribed, but forests lose water they need for species and to resist fires.
Our tax dollars should be used to tell people to stop burning carbon. Instead of mollifying mostly men who want to drive gas guzzling vehicles, every opportunity should be taken to encourage people to reduce their carbon footprints. Especially visitors who like forests and arrive by carbon burning vehicles must be told that they are contributing to the problem and need to change their behavior.
To the folks who say fires are inevitable, I partly agree. More fires are inevitable. We broke the climate, so we now own all the forests, even in the wilderness. We will have more fires, and some species of trees will no longer be able to live where they stand now. We need to decide what to do about them, and in some cases, we should condemn and even log those trees. But reducing carbon emissions likely requires delaying and limiting fires. Fire policy must combat the Climate Crisis, not exacerbate it.
Maybe the climate will collapse completely. But we must try to do something about it. And no person ought to be able to say “I didn’t know”.
If any of this is news to you or convinced you to change your mind, then please recommend and share this story widely. Truth needs help catching up to lies.