Guest Essay by Kip Hansen — 12 February 2025 — 750 words
A new study published in Nature Communications on 10 February 2025, “A fire deficit persists across diverse North American forests despite recent increases in area burned”, Parks et al. (2025), states:
“…despite increasing area burned in recent decades,… a widespread fire deficit persists across a range of forest types and recent years with exceptionally high area burned are not unprecedented when considering the multi-century perspective offered by fire-scarred trees.”
Let’s review that one more time:
“Wildland fire was common and widespread across many forests and woodlands in North America prior to the late 19th and early 20th centuries. In subsequent decades, fire exclusion—the practice of preventing and suppressing nearly all wildland fires—occurred as the result of the disruption of traditional burning, livestock grazing, and active suppression of human- and lightning-ignited fires. As a consequence, average annual area burned since the late 19th and early- to mid-20th centuries is generally less than that experienced under historical fire regimes across many North American forests, resulting in a widespread 20th century ‘fire deficit’ relative to earlier time periods.”
Note: The authors use “the term ‘traditional burning’ to encompass both Indigenous fire stewardship and post-colonization traditions of burning that were widely adopted in the eastern United States.”
Here’s their findings in one simple table:
[ click here for full sized image in new tab/window ]
The ecoregions are shown in this map:
The table shows that only one single region, the Taiga & Hudson Plain, in Northern Canada, had had more fires in the 1984-2022 study interval than would be predicted based on the burn scar data prior to 1880.
The study gives a conceptual explanation of the causes and effects as:
[ This figure has a rather long explanation. See it by viewing the image in its full size here. ]
The study summarizes its results as:
“Overall, contemporary fires (1984–2022) burned NAFSN [North American tree-ring fire-scar network] sites less frequently than fires during the historical reference period (pre-1880), indicating that a substantial fire deficit persists and is still accumulating across many forests and woodlands across the United States and Canada (Table 1). Based on the historical fire-scar record, NAFSN sites collectively would be expected to have burned 4346 times from 1984– 2022, yet they burned 989 times, or only 23% of what would be expected under the historical fire regime.”
The mass media would rather focus on studies such as “U.S. fires became larger, more frequent, and more widespread in the 2000s” , Iglesias et al. (2022), found in Science Advances. Iglesias et al. only studied fires since 1984. Looking at Parks et al. (2025) Figure 4 above, we see that time period as the raging fires fed by 100 years of fire deficit.
Bottom Lines:
1. Claims made repeatedly in the mainstream media that wildfires are getting more common and more severe are not supported by the findings of this study.
2. When looked at over the last 200 years, we have a severe fire deficit, not an excess. In the ecoregions studied (U.S. and Canada), fires have been far less frequent and the result is a fire deficit. This is true of all the ecoregions except the most northern parts of Canada.
3. The long-term fire deficit, unburned wildlands, sets up wildlands for more fiercely burning fires that consume all the extra fuel left by the lack of fire.
4. Parks et al. (2025) has a very interesting discussion section that covers possible long-term effects and regime shifts that might result from the century of fire suppression.
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Author’s Comment:
Fire is always a news worthy topic. Humans seem, even in our technologically advanced era, to be fascinated by fire while at the same time, depressingly ignorant of its causes and effects. This is seen all over the United States in the building of highly flammable homes in our forests and, as in Los Angeles, on indefensible hillsides covered with incendiary brush and grasses.
With that in mind, the Washington Post ran a very interesting story on “What the homes that survived the L.A. fires reveal”.
It is no mystery why some recent fires have been particular hot. The basics of fire have not changed: fuel + oxygen + heat = fire. More fuel with adequate oxygen makes hotter fires.
Studying short-term data sets for long-term phenomena is not good science.
After uploading the above essay, I found that Roger Pielke Jr. has picked up on the same study. His piece is The North American Fire Deficit.
Thanks for reading.
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The greens seem to have two themes, one being carbon storage (as scientifically illiterate as that term is) and Nature Knows Best.
The first leads to a taboo against releasing Satanic Gasses.
The second leads to opposition to any management of wildlands. Europeans never encountered “forests primaeval”, as Native Americans managed woodlands and chaparral for their own purposes, such as improving hunting. But Bambi and Smokey Bear occupy their minds rent free.
Tom ==> Environmentalism itself is a conservative movement — by its very definition. It seeks to conserve various environments for the future.
What we know as “The Greens” today tend to be left-leaning liberal progressives. That sets up an internal conflict when they attempt to engage in conservation — which is conservative in the greatest sense.
Thus we see them doing things that seem nutty.
They want preservation, not conservation. The are “preservationists”, not conservationists. Which in an ever changing landscape affected by bugs, fire, drought, etc., etc. is impossible. A climax forest WILL be replaced one way or another at some point, usually a “stand replacing” fire. They don’t realize management can weed out dead trees, push start forest growth by thinning and selective logging and speed up reforestation of decadent stands by clearcuts and quickly restocking. They want no management that yields timber because evil profit is a result so they are both scientific and economic illiterates. Not to forget the 90’s version of hippies tree siiting in 45 year old third growth Redwood they considered “old growth”. Unfortunately over my time in the woods over 40 years land management agencies that had folks who knew local landscapes and how to work with them were replaced by ‘ologists and Smokey the Social Justice Warrior. Perhaps the recent societal realization that common sense has been far too uncommon will eventually trickle into land management.
Back around 2008 the beetle kill hit at the same time of the mortgage crisis deal.
I stopped up on Stemple Pass around that time and hiked to the north up on the
ridge one afternoon just to see the forest. What I saw was stunning, nothing but dead trees in every direction as far as I could see. Except to the east which there
were several sections of private timber ground which was green and healthy..so
curious. Government timber dead, private timber green and healthy. John Muir
the Sierra Club founder and Gifford Pinchot the national forest principle had an
effect still seen today in the timber ground. When the National Forest units
management went from local individual management to central management
back at the Ivory Towers in Washington DC things really changed which I’m sure
you have seen. Kip and the authors need to spend some time in my area and see
what the forest has become. Then go over to Helena and watch the VLAT’s
in action…This study sounds like it came from the current forestry academic
world running things..
Previous data I’ve seen showed an abrupt drop off in the 1930’s. This correlates with the formation of the CCC and forest management
Mike ==> This study puts the start of fire suppression at the late 1800s. Pretty much entrenched by 1920-1930.
Mechanization sped it up a lot. A cat can do much more than 20 dudes with pulaskis.
I’m guessing that the upturn starting just before 2,000 is when California turned blue.
Alan ==> I am a California surfer boy (well, was in my early years). I watched the hills surrounding LA burn almost every summer in the 1950s and 1960s.
And now they have easily flammable houses in those hills. 😉
bnice ==> Yes, exactly so, see the WaPo article.
Kip ~ Indeed. I grew up near Santa Monica in the 1940s and 50s and my dad was an LA city fireman. I can attest that wildfires in the hills in Autumn and late Summer happened somewhere in the region most every year. Cabrillo, the first European explorer in the area called San Pedro Bay where LA Harbor lies today Bahia de los Fumos due to smoke from a fire burning in the area. And Richard Henry Dana in “Two Years Before The Mast” mentions that the citizens of Santa Barbara were driven to the beach to escape a recent wildfire. That fire would have been in the late 1820s or early 1830s.
What seems different today is the large number of (very expensive) houses built in very rugged terrain where adequate brush clearance is nearly impossible and road access for fire equipment and/or evacuation is extremely limited.
You lack confidence in the 4WD capabilities of goats!?
Don ==> You have your facts and history correct. Humans just don’t seem very good at learning the lessons of history.
Another key fire management effort is logging. Logging can thin forests, create fire breaks and add access with the logging roads to allow access to fight fires. Idiots stopped a lot of logging to save the Spotted Owl habitat. The resulting extra fires and fire extent == a lot of extra crispy critters.
The boreal forests are about 8000 years old. Yet the trees average about 140 years old. So forest fires that consume the trees must be a fairly common event….just not something human adulthood recognizes as a continuous phenomenon due to its geographical randomness. Insect infestations and wood rot don’t provide mass closure until you add forest fires into the mix.
Not those in cities. I can show you immense changes around Missoula area forests in the 45 years in the area. Then again I logged so spent my workdays on the mountain. Hunted and fished on weekends.
A personal related story concerning my Wisconsin Uplands dairy farm.
The region was first settled in the 1880’s after the last of the Indian Wars in those parts. (Military Trail from Madison to Dodgeville, now a state park hiking/dirt bike trail, was built for that purpose. The northern Wisconsin Reservations now ‘house’ those defeated tribes.)
When first settled and farmed, the area was open oak savannah inhabited by a few bison and lots of deer, turkey, grouse. The oaks were all burr oaks with very thick bark to withstand relatively frequent prairie fires, whether natural or set by the Native Americans. A burr oak sapling more than about 10 years old will usually naturally survive. And is helped to form its natural crown spreading shape, because the trunk and crown grows while lower branches are killed.
Some of those majestic burr oaks (easy 6 foot diameter at chest height), now old, still stand in my pastures. Rotted hollow cores make great feral honey bee hives.
But all the steep ravines and hillsides we cannot farm or usefully graze have completely filled in with hickory, white oak, red oak, and hard maple—in a sense all invasive tree species to what was just 150 years ago an open oak Savannah.
We don’t do it because now a largish working farm, but a neighbor down Penn Hollow on about 80 former pasture acres with a vacation cabin brushes his fence line then sets a deliberate burn prairie fire every third or so spring to restore the oak Savannah. We have given him bushels of pasture acreage burr oak acorns to plant to help things along. Of course, with his burning frequency he also had to protect those young saplings by simply brushing a circle around them. For the oldest, he now no longer needs to do that. His little oak savannah is coming along nicely after about 30 years.
Earlier this century, I was working on a forestry project that required the clearing of all invasive vegetation/trees less than 100mm diameter leaving the larger endemic tree species in place. This was done using large forest mulchers – much larger than the skid-steer ones available now. The process left a beautiful, open woodland with a woodchip forest floor.
One of the local farmers, now in his late 80’s commented that the area now looked like it was when his father used to take a horse and dray through the area to get to town, not the tangled tick and feral pig ridden mess it eventually evolved into.
Mulch, baby mulch!
jayrow ==> That’s interesting. Is there a web page that describes that work?
Kip – just search for “forest mulchers” and a large variety of types and sizes will be found – even ytube clips. Below is an example. The contracting group used for the project described above also had contracts to keep vegetation clear under high tension power lines and easements sited through forested areas.
The image below shows the process – the smaller brush can be driven through, while the larger trees are knocked down and driven over with the mulching head. This image comes from ytube – not from my example.
jayrow ==> Thanks for that — very neat.
The USFS did just that in an area in Monument, CO area to reduce fuels given the proximity of residential homes in the area. Folks were in an uproar. Nevertheless, after a year, the ground came back nicely and created a more beautiful forest area with more grasses and wild flowers. People who complain don’t realize the forests of today look nothing like they were a 100+ years ago as shown in books of CO in those historical/nostalgia days.
Kip,
“Claims made repeatedly in the mainstream media that wildfires are getting more common and more severe are not supported by the findings of this study. “
Their abstract begins:
“Rapid increases in wildfire area burned across North American forests pose novel challenges for managers and society.”
“we have a severe fire deficit, not an excess”
We like our deficit and spend a lot to maintain it. Fire 400 years ago did not much damage. Now it burns whole towns.
Nick ==> Read this essay, read the paper in full, read Pielke Jrs. piece on it.
You hit the mass media spin exactly right — there seems to be more hotter fires now than in the 1980s/1990s. That part is true.
The reason for that is the point of the study featured here today: There has been a long term fire deficit, almost 100 years of it. Thus, the continent is covered with forests with a huge fuel overload, that now burns hotter and can spread wider.
It is a matter of time scale. Short term – more hotter fires (but far less than in the late 1800s).
Compared to 1700-1900, we have far FEWER fires and FEWER acres burned.
And we are still accumulating even more Fire Deficit.
Kip,
I read the paper sited. It seems clear our fire suppression efforts and lack of prescribed burns are the problem. This was a similar conclusion to a post/video a while back about invasive grasses(the fuel) and fires…. In fact, in this paper they site the success in Florida’s use of prescribed burns. So the solution seems simple, is that we have to manage our forests better and do prescribed burns. They seem to mention climate change in an obligatory way, when in reality it has little or nothing to do with the fires today.
So, instead of focusing on climate issues for forest fires we should simply manage the forests better, that would solve the problem. Am I missing something?
JViola ==> Failure to manage our wildlands, our forest, and our grassland has led to disaster after disaster.
Weather plays a part on fire regimes — in LA, it is called “fire weather”.
Climate — the climate type of region — and not “climate change” — is important. Much of the West Coast is Fire Country — and ecosystems are shaped and kept up through repeated burning.
Ok I see Pielke Jrs. piece comes to the same conclusion. I am happy to say they are doing burns close to our home in Lake Tahoe:)
Nick
beginning to think you have a serious issue with any view in any subject other than your own.
I think the serious issue is a sort of tunnel vision, where Nick focuses on one narrow image and is unable to see the entire picture, a forest-for-the-tree-type situation. Or maybe more like a dog with a frisbee who doesn’t see the car coming.
Great Fire of 1910 – Wikipedia
Take a seat, the adults are having a discussion.
Nick do I need to point out 400 years ago there would be 0 towns to burn down in either USA or Australia. Ergo USA foundation is 1776 and Australia 1788 and 2025-400 = 1625 and graph above starts before that.
Towns have increased from 0 to many over that time and it makes it a little hard to use as an indicator it needs to stay as area probably with caveats because of change in use. What would be amazing if towns were not burnt down these days given there number increase.
I get the thrust of your answer but it also contains this weird non sequitur statement.
Bushfires shouldn’t burn any towns if proper preparations are allowed to be in place.
It all comes down to “the 7 Ps”
I am not sure people also build in dumb places like surrounded by tress.
Doing that doesn’t help, either.
That’s a bit like building in river beds.
“Nick do I need to point out”
No, you don’t. The point is, we need that deficit.
Nick, you often offer good insight here, but you’re not making any sense at all on this one.
You seem to be saying that we can’t allow burns such as those that occurred 400 years ago because that would necessarily mean burning towns and houses. I don’t think anyone is arguing for allowing indiscriminate burning. They’re merely observing that the greater number of fires that previously occurred reduced fuel loading. Higher fuel loads demonstrably lead to more uncontrollable fires. The reasonable conclusion is that smaller, controllable burns on a regular basis, or allowing more timber harvests in some cases, would put the system back into balance.
But I suspect you knew that.
The point is that we’ve been able to build towns and not have them burn down, until recently.
No, I think the point is that maintaining a fire deficit without controlling the fuel load and/or adapting construction to resist the increased risk leads to catastrophe and blaming it on “climate change” is a rather pathetic attempt to avoid responsibility for poor management and myopic environmental hysteria.
Nick ==> We have built towns, and whole cities, and and they don’t all burn down. But it is not only “recently” that some towns do burn down.
The disastrous town burning recently have all been directly caused by building flammable homes in the WUI (Wildland Urban Interface) — with homes directly in the forests, surrounded by forest without a proper safety zone around the town. In Colorado, a prairie fire burnt a town as local laws forbade cutting a fire break around the town.
Paradise, California is a example of the problem.
(PS: I have no idea what you mean by “we need that deficit”.)
Fire 400 years ago did not much damage.
The trees would probably disagree about that.
Now it burns whole towns.
400 years ago there weren’t exactly a lot of towns to burn.
Growing up in south Mississippi in 60s-70s I remember controlled burns of pine acreage on a yearly basis, and as a teen got to work fire lines for State Forestry service. It was to keep brush down and to suppress certain insects. Fast moving fire did not damage the pines, and clearing the brush made harvesting trees for pulp and lumber a lot easier. Also, after cutting trees the limb wood would often be pushed into long rows and burned.
2hotel9 ==> Thanks for the history lesson. The fire deficit is built up when those types of burns aren’t done and natural fires (lightning strikes and the like) are suppressed as quickly as possible.
Was down to visit during Christmas and was discussing wild fires with my brothers, they say it is becoming a problem in recent years because fuel load is increasing in many areas. The huge plots of pine trees grown and harvested are still maintained while a lot of acreage privately owned is not. Also a lot more residential building in areas that were long open, so more property damage now. Mulching operations are more common now, GP has been doing that and using it in paper processing, so less waste in logging now. There are viable answers, just have to force the greenunistas to stop blocking them.
What kind of a forest land is Los Angeles? Or does it count separately?
Curious ==> The foothills directly surrounding Los Angeles– where recent fires occurred — are “chaparral and coastal sage scrub“. We are talking of fires in all types of “wildlands”.
The Angeles National Forest.
https://www.fs.usda.gov/main/angeles/home
FTA: “The Angeles National Forest is an urban national forest in the center of an ever-changing population and provides a place for surrounding communities to experience solitude, quiet, and enjoy unique recreation opportunities.
That may be an insight into the problem. An agency tasked with forest management is more interested in being a tourist and recreation brochure.
I’m skeptical of any actual “indigenous fire stewardship”.
Jeff ==> What that means is the Native American’s used intentionally set fires as a method of reshaping the environment.
Seems like a feelgood story. But I’m still skeptical.
A lot of indigenous tribes used fire to clear areas for crops, still prevalent in South America and parts of Asia. Burn clear an area, crop it till soil depleted, burn clear another area. Burning actually puts nutrients/minerals into the soil.
No. For documented sure in aboriginal eastern AUS and western Native American US, the forests were managed by ‘uncontrolled’ deliberate burns. Was necessary to provide more easy hunting of more game.
For example, Rocky lodgepole pine will not open cones and reseed unless a burn. A mature lodgepole pine stand is ‘barren’ for most wildlife except porcupines.
My brother got a PhD in elk management. Were it not for selective forestry ‘patchwork’ clear cuts by the likes of Weyerhauser, the only way mountain elk could be maintained at the levels they are is sporadic forest fires.
Lodgepole have 2 types of cones, the fireproof ones have a coating that protects them.
Indeed, in wildlife ecology we learned that for the most part climax communities, i.e. old growth forests are very restricted in biodiversity and limited sources of food for humans and animals, while succession communities following fire or other disruption become very productive and diverse. The idea of a static environment, a “preserved” condition is the opposite of natural.
“Rocky lodgepole pine will not open cones and reseed unless a burn.”
The regen from the last bug kill is thick and a good 20-30ft tall in my area.
” the only way mountain elk could be maintained at the levels they are is sporadic forest fires”
The elk were originally a plains animal and got forced into the mountains . Weyerhauser
and the other timber company’s changed their tax structure to a REIT and that
radically changed their management practices from what I’ve seen. That and
the wolf reintroduction..
This was mentioned by clear thinkers many times here in Australia. They were called climate deniers. Fuel build up is estimated at 10 tonnes/hectare/year. (11 tons/2.5 acres/year). It is lazy and ignorant to blame the climate rather than something measurable. The bastards!
Kip – nothing in this much surprises me, those are exactly the results I would expect given a little thought and historical knowledge. EXCEPT:
How did they quantify things for the Canadian and American prairie regions? I’m not saying the results are wrong, perhaps they have other proxies, but the prairies by definition have a tree deficit. There’s no trees to have scars south of the tree line. Well there’s the odd one, but they are few and far between. The map shows very few of those hexes in the red and blue shaded regions and only a single one in the purple region. Perhaps I’m not understanding the methodology, I did not read the actual paper, but that seems rather sparse to me.
DH, see above. There were NOT only two environments, forest and prairie. There were at least three. The third was a transitional oak savannah, comprising at least all of northern Illinois and southern Wisconsin. See above for details.
Short grass prairie which extended into southern Minnesota as well, transitioned into tall grass into the Dakotas and West. Even fewer trees save for river bottoms. Burned regularly as well which is unsurprising. Bison did the tillage.
David ==> As you can see by the map the hexs are fewer in the Great Plains — the paper is very specific about methods. You can dig deeper if you need details.
s/heat/ignition source/
cocky ==> Yes, one can substitute “ignition source” for “heat” Possibly more correct.
kip ==> it was picky, but unfortunately, far too many people think that just having temperatures a few degrees above average for the time of year is a guarantee of catastrophic fires.
Even a hot desert day is around 325 – 330K; well short of the 560K+ ignition temperature of dry grass.
Parks Canada blocked tree thinning in Jasper National Park in Alberta.
A key reason the town burned up last summer.
Parks Canada is in the Environment Ministry headed by a rabid climate alarmist who has a criminal history of trespass and Mischief.
(The trees in question are dead, killed by pine beetles which were an epidemic in western Canada.
Keep up the good work Kip.
The Green disconnection from reality is nowhere more obvious than in their attitude towards wildfire management! They claim to cherish “aboriginal lore,” yet refuse to allow any burning that may be necessary to replenish the soils in many ecosystems.
There are only two options for proper management; controlled burns, which are dangerous when inept bureaucrats make the decisions; and undergrowth cutting with small slash piles burned off fire season. Allowing the US timber industry to make the decisions again would prevent the large out-of-control fires we have been seeing in recent years, and would also provide more high quality lumber for the construction industry, which is why the Greens will oppose it! Why build when you can burn?
Abo man ==> You’re not wrong. Oregon has done a lot of “undergrowth cutting with small slash piles burned off fire season”. I was through there ten years ago, and the forests in some places were dotted with sash piles waiting to be burned.
Its interesting to observe, while watching various TeeVee series or movies filmed in the Los Angeles area, the growth on the hillsides and even over-growing the fence lines on the roads up in those areas … I was watching a live stream a month back with Dr. Reed Timmer and crew and noted growth present day even, over the fences as well as trees along side the roads – how this growth proceeds with the low-levels of rainfall I do not know.
Jim ==> I grew up in LA. The scrub and brush in the hills needs very little water to grow and is very successful even in droughty years. That is the climate type vegetation.
Some homes make this even worse by watering the property-line vegetation in the belief that it will thus be greener and thus less flammable.
Griffith Park often watered the vegetation along roadsides, far from any buildings, to prevent fires from cigarettes thrown out of passing cars.