Why Worse Wildfires? Part 1

What’s Natural?

clip_image002Guest post by Jim Steele

There are several theories trying to explain the recent uptick in wildfires throughout the western USA. Some scientists blame increased human ignitions. Others suggest accumulating surface fuels due to a century of fire suppression. Others argue landscape changes and invasive grasses have amplified the amount of easily ignited vegetation, while still others blame climate change. What’s the Sage Grouse connection? Like human communities, the Sage Grouse’s habitat is being threatened by fast spreading wildfires, and that increase in bigger wildfires in sagebrush country is due to invading annual grasses, like cheatgrass.

Historically hot dry sagebrush habitat rarely burned (just once every 60-100 years) because slow growing, patchy sagebrush only provides scant surface fuels incapable of supporting large and frequent fires. But the invasion of introduced annual grasses, like cheatgrass, has changed all that. As one wildlife researcher lamented, “The color of Nevada has changed from a sagebrush silver gray to a cheatgrass tawny brown since the 1990s”. Likewise, in the 1800s California’s hills were covered with perennial grasses that stayed green during the summer. Now California’s hills are golden brown as highly flammable annual grasses have taken over.

Cheat grass-dominated sagebrush habitat now burns every 3-5 years, up to 20 times more frequently than historic natural conditions. Extensive research on the effects of cheat grass found habitats with high cheat grass abundance are “twice as likely to burn as those with low abundance, and four times more likely to burn multiple times between 2000-2015.” What makes cheatgrass such a problem?

Invading annual grasses germinate earlier in the season and deprive the later-germinating native grasses of needed moisture. These foreign grasses die after setting seed, leaving highly flammable fuels that can burn much earlier in the year and thus extend the fire season. Eleven of the USA’s 50 biggest fires in last 20 years have been in Great Basin sagebrush habitats, where invasive cheatgrass is spreading. Nevada’s largest fire was the 2018 Martin Fire. Rapidly spreading through the cheat grass, it burned 439,000 acres, a burned area rivaling California’s largest fires in recorded history.

The 2012 Rush Fire was California’s 4th largest fire since 1932, burning 272,000 acres of sagebrush habitat in northeastern California. It then continued to spread burning an additional 43,000 acres in Nevada. The 2018 Carr Fire was California’s 7th largest fire and threatened the town of Redding, California. It started when a towed trailer blew a tire causing its wheel rim to scrape the asphalt. The resulting sparks were enough to ignite roadside grasses. Grassfires then carried the flames into the shrublands and forests, where burning grasses served as kindling to ignite less-flammable trees. Likewise, grasses were critical in spreading northern California’s biggest fires. In southern California, as humans ignite more and more fires, shrublands are being converted to more flammable grasslands.

Wildfire experts classify grasses as 1-hour fine fuels, meaning dead grass becomes highly flammable with just one hour of warm dry conditions. When experts estimate impending fire danger, they calculate the extent of a region’s fine fuels to determine how fast a fire will spread. The amount of small diameter fuels like grasses that can dry out in an hour, as well as twigs and small branches that dry out within 10 to 100 hours of dry weather, determine how fast the winds will spread a fire. It does not matter if it was wet and cool, or hot and dry during previous weeks or years. Just one hour of warm dry fire weather sets the stage for an explosive grass fire. Decades of climate change are totally irrelevant.

Some scientists point out that certain logging practices also spread “invasive grasses”. For that reason, California’s Democrat congressman, Ro Khanna, has been arguing that the U.S. Forest Service policy to clear cut after a wildfire is making California’s forest fires spread faster and burn hotter by increasing the forest floor’s flammable debris. Khanna warns, “Because we don’t have the right science, it is costing us lives, and that is the urgency of getting this right.”

Bad analyses promote bad remedies and blaming climate change has distracted people from real solutions. The “cheatgrass” problem will continue to cause bigger fast-moving fires no matter how the climate changes. But there are several tactics that could provide better remedies. Holistic grazing that targets annual grasses before they set seed is one tactic. Better management of surface fuels via prescribed burns is another, as well as more careful logging practices. And re-seeding habitat with native perennial grasses or sagebrush could help shift the competitive balance away from cheatgrass. In combination with limiting human ignitions, (see part 2), all those tactics may ensure healthy populations of Sage Grouse living alongside safer human communities.

Jim Steele is Director emeritus of San Francisco State’s Sierra Nevada Field Campus and authored Landscapes and Cycles: An Environmentalist’s Journey to Climate Skepticism

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69 thoughts on “Why Worse Wildfires? Part 1

  1. “There are several theories trying to explain the recent uptick in wildfires throughout the western USA.”

    The answer: anything but CO2.

    • CO2 via climate change can only cause fires indirectly by increasing the number of hotter drier days. But there isn’t a significant increase in the number of such days and that is a problem for the climate change attribution. CO2 can also increase the likelihood of large fires by a more direct mechanism by increasing the rate of plant growth thereby providing more fuel for fires. Global greening is a real effect and greater fire risk is one of its consequences.

    • “The answer: anything but CO2.”

      Correct. We use CO2 to put out fires not start them.

      Glad to see you are finally on-board, Loydo.

      • I agree. We are generally very good at mitigating for the worst that mother nature can throw at us; that is until politics gets in the way of establishing sound policies based on scientific facts. I can’t think of many that are worse than some of the moronic policies concerning forest management that virtually guarantee horrendous fires by ensuring a build up of fuel while suppressing them until the worst possible conditions of wind, humidity & temperature finally come along to make them impossible to suppress at all. It’s clearly insanity to retain those bad policies then expect a different outcome the next time.

    • “The answer: anything but CO2”

      How does CO2 cause a wildfire? By increasing the heat in the atmosphere, you say? Most of the areas burning in California are cooler today than they were in the 1930’s, when CO2 levels were not a significant factor. More CO2 today, has not resulted in a warmer climate in California, it is actually cooler today than in the past. So how does CO2 cause California’s wildfires when it is cooler now than in the past? Apparently, CO2 is *not* causing unprecedented warming in California.

      • There is an accelerationist aspect to this. There is an effort underway to block efforts to mitigate fire risk because it might detract from the central message of cutting the use of fossil fuels. It is like they want to maximise damage from fires to add strength to their climate change argument.

    • CO2 has increased the carbon cycle; uptake is reportedly 2X what it was 50 years ago.

      Given that that increase in uptake hasn’t decreased CO2 concentration suggests that animal respiration has kept pace with the increase in uptake and also increased by 2X so why wouldn’t there also be a concomitant increase in fire?

      It appears to me that an increase in overall fire would be an expected consequence of a greener earth, fatter faster plant growth producing more fuel more quickly.

    • How about forest fire models developed in Australia in the 1970s, propagated throughout the world, and then initialised with actual real world data in the 1990s? Yeah! I say bollocks too!

      Proper forest management is what is required and has been lacking in Australia for at least 40 years!

      All in the name of “sustainability”!

    • Can you come up with even a shred of evidence that CO2 has played a role?
      On the other hand your fervent conviction that CO2 is the cause of everything bad is so darn cute.

      PS: Once again Loydo demonstrates that she can’t refute anything written. She’s only good for kindergarten grade snark.

    • “The answer: anything but CO2.”

      Yep. Glasshouses NEED CO2 + warming to grow crops, fruit and vegetables.

  2. Excellent post as ever Jim Steele, a voice of sanity amidst the global madness . . . “blaming climate change distracts people from real solutions” pretty much sums up the whole gig in half a sentence. Bravo!

  3. Various governments in Cal have been claiming that climate change was the reason the fires were so much more intense and that it was going to get worse. But they did nothing to prepare for what they claimed was happening.

    We all know that the oil in the engines of our cars is slowly burned as the car is driven. The supposed reason does not matter. Hey, stupid, preventive maintenance.

    Mr. Steels states a problem and recommends a cure. Perhaps if he had stated that by decreasing the fuel load CO2 emissions would be lowered he could get a $3,000,000 grant to study the problem. I wish I could put sarc after that but I suspect it is true.

    • Hey, stupid, preventive maintenance

      Something PG&E and the CPUC treat as an unnecessary nuisance. I suggest there are far too many STUPID, intentional, or criminally negligent HUMAN ignition sources. With PG&E leading the pack.

  4. Very interesting, my grandparents had a 160 acre farm in central Texas during the severe 1950s drought and I recall fires on a few dozen cleared acres with inadequate grazing. The worst one required some tractor work and fortunately the wind was not too bad. They probably started from a road, concern was maybe from a cigarette which my grandfather showed me how it could have been so ignited. Smoking was common and there were two roads adjacent to where the fire started, probably from a major highway.

    On the central Texas coast where I live a similar but very severe fire happened back then, and grass fires are a continual worry because of the chaparral maritime climate. Development is removing a lot of the trees, favoring grass (and concrete), but the very flammable understory is removed partly for fire control. Unfortunately it has taken out habitat for the migratory birds. I just had the grass cut for someone with mostly wooded acreage for fire protection and better access around their habitation.

    I suspect the grasses in both situations were native, but grasses are complicated and very diverse for us aquatic types. Both of these had Johnsongrass, Sorghum halepense, which I have read is native although my great-grandmother told me that her family brought it from Kentucky. She also told me she was chased by a hoop snake as a child, now apparently extinct, but she did know her flowers. Johnsongrass thrives in disturbed soils, but requires a lot of moisture, hence its success.

    • My family and I live on a ranch southwest of San Antonio. In earlier years ranchers brought in an African native grass locally referred to as “Guinea Grass.” It grows in thick groves to heights taller than a man. Once it ignites with any wind, it is very hard to extinguish. It particularly likes to grow under live oak trees. We had a fire a few years ago which swept through the grass, killing live oaks that must have survived many fires. It stopped only when it got to the river. I tried to get rid of it by spraying, but that was a losing battle. I finally had to put cattle back on the property. Guinea grass is their favorite grass, and it rarely gets higher than a few inches now.

      • Very interesting, what county is that? My grandfather’s farm was the focus of what is now the town of Live Oak, I spent WWII watching planes from Randolph AFB. He sold it before the height of the drought, but as I recall trees survived. It was in the Blackland Prairie, not many oaks. He also had property S of town which I never saw. Until a few years ago my son had property in the Hill Country outside of Blanco, usual woods, prairie, creek and pond, no grazing. I sat down with a grass book and tried to identify species. All were native, nothing like you describe which sounds hard to miss, but some up to a meter. I had lots of Botany, but never a grass course, however.

        I still have family up there, will check it out. Old historical accounts had coastal prairie claiming grass that high, but don’t think it was in the shade. Indians burned at least some of it. Also I’ve camped in west Texas and traveled in the west, seen a lot of burnable country. Talked once to a botanist in Big Bend studying a grass fire after a wet spell, he said that’s what it takes, and lots of exotics get brought in.

  5. It is always such a pleasure to be educated by observation/empirical evidence-based arguments.

    I would love to have been taught by Jim Steele and take whatever opportunities I can to learn from him in middle age….

  6. Never mind invasive grass, how about invasive sagebrush.

    Some believe fire suppression and overgrazing by livestock have allowed sagebrush to expand its range and invade grasslands since European settlement. link

    • Overgrazing was a huge problem for promoting more grasslands but increased sagebrush is usually the result of lowering the water table . We restored a meadow that had been taken over by sagebrush because the hydrology had been disrupted. Fixed the hydrology and most of the sagebrush died, In drier areas like the Great Basin deserts in Nevada sagebrush is the naturally dominant plant

  7. This is the reason we have controlled burns in my AO: get rid of undesirable invasive plants. No one around here objects to it at all. In some place, goats are also sent in from a dairy goat farm to clear undesirable plants.

    So far, we have NOT had any such devastating fires at all (knock on wood). Must be the difference between common sense here and the lack of it in California.

    • Cheatgrass does well wherever the land has been disturbed like roadsides or from overgrazing. Humans have increased ignitions causing more frequent fires in scrublands which then convert scrublands to grasslands.

      • Further to the Sage Grouse problem:

        Cheatgrass is an Asian species introduced to North America accidentally in the late nineteenth century. Since introduction it has been remarkably successful at invading the sage scrublands of the Basin and Range province, transforming the landscape (especially burn scars) to annual grassland. It is of little nutritional value and is not eaten by grazing animals. It usually dries by June forming excellent fuel for wildfire early, thus extending the fire season.

        The plight of the Sage Grouse though, is not so much due to loss of sagebrush habitat, but to the proliferation of its primary predator, the common raven. Since being Federally protected under the Migratory Bird Treaty Act of 1918, raven populations in the Great Basin have exploded, and Sage Grouse and other ground-nesting species have been decimated. There will be no recovery of Sage Grouse populations until raven populations are controlled.

        • It doesn’t really matter if the cheatgrass is disliked by grazers, since we’ve eliminated most of them in central CA. The Tule Elk are almost extinct, Roosevelt’s are gone, and the only big wild herbivores we have left are deer or cattle. Deer browse rather than graze, and there’s active animus to cattle in CA from the safe space vegan crowd. So, nothing eats the grass. Then it burns.

    • More people, more disturbed land. On the five acres I live on, there’s tons of cheatgrass. Mowing does not get rid of it—it cleverly grows back about 2 to 3 inches tall and reseeds itself. It’s a very early grass, up long before native grasses. Plus, it comes back quickly in wet years. Native grass does not. Burning reportedly increases the volume of cheatgrass, so fires may actually make it worse. On my 140 acres in a relatively undisturbed area, there is no cheatgrass. As more people arrive, both cheatgrass and dandelions will increase in that area.

      Cheatgrass germinates in the fall and is an annual. The seeds can lie dormant for a very long time, making this very complex. We were told you can reduce spring growth IF you can apply a certain herbicide before the temperature drops below 40F. That’s not easy to do. And you have to apply every year. It’s not as effective as one would wish and only in areas that can afford to apply the herbicide.

      Cheatgrass is very bad for dogs—they end up with the dry seeds stuck in their toes and fur. It can work under the skin and cause problems. I have spent a fortune having cheatgrass removed from dog feet and fur, even with massive mowing of the area. I once picked 200 seeds out the fur of a 10lb pomeranian. From one trip outside, when she ran into a patch of the cheatgrass. It sticks to socks, digs into shoes. Can’t say if it’s more annoying than the grasses that make burrs, but I think probably so.

      It’s actually kind of pretty when it’s in the purple stage, a nightmare thereafter.

  8. Folks

    The world does not begin and end on the borders of these here United States. Explaining away the “fires as a result of climate change” hypothesis will take a worldwide viewpoint. What about theAmazon fires, the Lebanon fires, the Canadian fires, the Australian fires …. and so on ….

    Global Forest Watch, fire map

    https://fires.globalforestwatch.org/map/#activeLayers=viirsFires%2CactiveFires&activeBasemap=topo&activeImagery=&planetCategory=null&planetPeriod=null&x=0.000000&y=40.000000&z=3

    • The fires in the American west are due to many of the same underlying causes as those around the world. More people, more ignitions. Fast spreading fires require easily ignited 1hour to 100 hour fuels, fuels that dry regardless of climate changes. Lebanon fires have roared through scrublands similar to California during high wind events. All areas adjacent to mountains get high winds during COOLER times because as the mountains cool the winds roar down to the low lands. Those winds heat due natural compression and raise temperature and lower relative humidity. The fires in the Amazon are due to land clearing that has been promoted by the subsidized biofuels pushed by climate hysteria http://landscapesandcycles.net/amazon-fires-and-biofuels.html

    • If “climate change” is responsible for fires in Australia, explain why the first explorers observed vast areas burnt and burning . Explain why we had major fires in the 19th and early 20th centuries.

      The reality is that fires are a product of drought, and one of the more honest Australian experts on Climate has admitted that there is no reason a priori, why climate change will cause droughts. There are also at least three significant scientific studies revealing far more severe droughts historically, than anything we have recorded since European settlement.

      So good luck with blaming climate change for something that has been happening for millennia.

      The real problem, as found by every major inquiry into lethal Australian bushfires, is that we are not doing enough fuel management. Areas that would naturally be 9n a 3-5 year fire cycle, are on a FIFTY year rotation. If you don’t think this matters, you have never stood, waiting, for an intense fire to come to you.

  9. Even where invasive plants don’t cause disasters such as fires, they’re still a big problem that’s costing you money. The power companies in the Southeast, for example, spend millions of dollars a year trying to clear rights-of-way from Chinaberry trees, kudzu vines, and mimosa.

    • Where I live (Fraser River Delta, BC) the invasive plant Japanese Knotweed is a big problem. People used to chop them up, but one day I inspected a chopped piece and found roots growing out of it. The method of getting rid of the invasive species was helping spread them. Today they are injected with chemicals and left to die and seems to be effective but sites need to be revisited once more a year or so later for a final application.
      The problem with many invasive species are the displacement of food for the local wildlife. Don’t see much grass where I live except in playgrounds such as golf courses.

    • Cheatgrass has a very, very short grazing window. Plus, you need a lot of cattle to graze it down quickly, and public land may not allow that. One place called it “mob grazing”. Once the cheatgrass is grazed down, you have to move the cattle so they don’t graze down native grass. Native grasses are hard to get to grow back where the cheatgrass has taken over. It’s a slow process and requires dedication.

  10. A couple of scientist were researching knapweed in the NW a few years ago and discovered
    that a native fungus found in the soil gave the weed an advantage, termed fungal entropy. They found
    that the plant absorbs this fungus into the root system which then produces something like 20 different
    compounds of which 2 make the soil sterile to everything but knapweed. This allows a few invading
    plants to completely take over a large area in a few years. It’s thought that cheat crass has a similar
    advantage by some. I read that this fungus has been genetically modified to make the seeds sterile.
    I see the future of cheat grass going down this path in the future…but goats work well in the meantime.

  11. I would rather face a cheat grass fire over a chaparral fire. National forest surrounds our place, and 20 years or more ago, cattle grazing was allowed (logging ended long ago). Since grazing ended, the chaparral has grown thicker and taller, there’s been no significant controlled burning (spotted owl territory) to speak of. A cheat grass fire might spread faster, but a chaparrel fire is going to be a lot bigger in terms of flame size, and hotter, and last longer. I realize these conditions may only be local to our area (So. CA), but I question the advisability of grass vs. brush of any kind.

  12. Everyone forgets “Pyroterrorism”. Google that term. The U.S. Forest Service had a Conference on Pyroterrorism. In 2017, a Jihadist was arrested for arson. ISIS just released a demand for all followers to torch the Great Satan. This is not new. There are plans on the internet for remote-controlled incendiary devices. Report all suspicious activity.

  13. Jim
    Prior to organized suppression of wildfires, there was no economic incentive for arson. Now, unemployed people start fires so that they can be paid to fight them. Another example of unintended consequences. It is a very complex issue.

  14. Every major inquiry (We call them Royal Commissions) into Australian bushfires over the last 80 years has found that we need to do more fuel reduction burning.

    By a minimum of double the rate at which it is currently being carried out in South-Eastern Australia.

  15. Great post, Jim Steele, and, as usual, right on the money. As a geologist working and camping out a lot in northern Nevada I can assure you that you do not camp, or even loiter (work?) in a dead end canyon downwind with thunderstorms around in cheatgrass country. The fires in dry cheatgrass run so fast it is hard to imagine. Sage grouse? Tasty critters!

  16. Historically hot dry sagebrush habitat rarely burned (just once every 60-100 years)

    Please cite your sources. My research indicates that human beings have occupied the Great Basin for at least 11,000 years (and at least 15,000 years in So. Cal.). Those residents burned their habitats frequently. Anthropogenic fire was practiced every year, though not always on the same patch. The fire return interval for the average acre was less than 10 years. Another way to state this, using statistical survival analysis terms, is that the likelihood of any acre remaining unburned (surviving) was less than 10 years.

    Others suggest accumulating surface fuels due to a century of fire suppression.

    For at least 11,000 to 15,000 years the principal fire ignition factor was human beings, not lightning. The usage of “fire suppression” implies that for the last 100 years moderns have been suppressing lightning fires in sage brush, chaparral, grasslands, and currently forested areas. That is incorrect. Historically (for millennia) the ignition source across North America has been human beings. What was suppressed is the indigenous cultural practice of land management via anthropogenic fire. The resident indigenous people were decimated by Old World diseases and removal to reservations. That is why anthropogenic fires ceased.

    It is a common misconception to assume that nature is a deterministic machine that operates or operated in the absence of humanity. This misconception arises from a neo-Puritan neo-Victorian world view that discounts the scientific historical true fact that human beings have played a dominant role in nature since time immemorial. Ecological analyses that deny historical human influences upon or to the environment are simply wrong. “Solutions” that rely on faulty analyses are unlikely to succeed — on this point we agree.

  17. Mike Dubrasich,

    Please site YOUR references Mike. One reference to the 60-100 years sagebrush cycle can be found if you click on the Sage Grouse link in my essay.

    Furthermore fire suppression has very much been a factor and it is you whose argument is very much incorrect. Clearly you do not have a fire ecology background. Indeed native Americans were lighting fires but I identifying how much versus lightning is not quantifiable. Europeans began suppressing fires whether started by Native American or by lightning. For decades fire ecologists have been warning fire suppression will result in bigger more intense fires. Many argued we need to manage the forests with prescribed burns in much the same way Native Americans hd done.

  18. Mike Dubrasich:

    “The fire return interval for the average acre was less than 10 years. Another way to state this, using statistical survival analysis terms, is that the likelihood of any acre remaining unburned (surviving) was less than 10 years.”

    So, you are saying every acre of sagebrush habitat burns at least once every ten years? Have you ever even been to the Great Basin? If you had you would realize how stupid those statements are.

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