Homes Lost to Wildfire: It’s the Grass

CNN story:

Over the last three decades, the number of US homes destroyed by wildfire has more than doubled as fires burn bigger and badder, a recent study found. Most of those homes were burned not by forest fires, but by fires racing through grass and shrubs.

The West is most at risk, the study found, where more than two-thirds of the homes burned over the last 30 years were located. Of those, nearly 80% were burned in grass and shrub fires.

30 thoughts on “Homes Lost to Wildfire: It’s the Grass”

  1. Where I live in a grassy area, I’m not sure it’s climate at all.
    Every year grasses dry out before greenup. There has never been snow cover all winter. Remember, it snowed the day after the Marshall Fire. Frequent high winds are common.
    We have animals that reduce grassy fuels and also convert it to edible protein.
    As more people move in, they do things that cause ignitions, as do electric lines and other electric infrastructure. The only thing that works around here in this environment is rapid initial attack.

    This 7 mile prescribed burn in Borger Texas also worked.

  2. Many of us in the forest protection community have been saying the same thing for decades now: Many of the most costly, home-destroying wildfires have little to nothing to do with “forests.” Us same folks have been also urging for decades that a focus must be on the Home Ignition Zone.

    • While homes in grass and shrub cover types are the majority of homes lost, many thousands of structures are in or near forests. Yes, defensive space is important, but forests around communities — including outside the 1-kilometer zone some folks say is the most important — need to be managed for overall health and fire resilience and to decrease fire intensity, as some of us have been saying for decades.

      FWIW, Oregon has initiated a program under which home and business owners may request a defensive space assessment by folks with the State Fire Marshal’s office. I requested such an assessment — it’s scheduled for April 2. I plan to write about the process and the report on my property for the local newspaper — I write a column called The Woodsman. I’m sure they’ll note that my defensive space can be improved.

    • Matthew, the Borger prescribed burn was not in the HIZ.. as I have been arguing for years, most people don’t want wildfire running through their communities, evacuating pets and livestock, burning up telephone and electric lines and all that. The burn kept the fire from going through town.

      • The National Fire Protection Association says this about the Home Ignition Zone.

        What is the Home Ignition Zone?

        The concept of the home ignition zone was developed by retired USDA Forest Service fire scientist Jack Cohen in the late 1990s, following some breakthrough experimental research into how homes ignite due to the effects of radiant heat. The HIZ is divided into three zones.

        The immediate zone of the Home Ignition Zone is just up to 5 feet away from the house, while the extended zone goes 30 to 100 feet. In most all circumstances the HIZ is entirely on private property and entirely the responsibility of the homeowner.

        • Matthew, I’m well aware of the home ignition zone developed by Jack Cohen — groundbreaking work. But I’ve taught wildland fire/fire ecology classes and other forestry classes for 25+ years (I also was once a wildland firefighter). In the era of megafires, and more megafires in the offing, focusing solely on the home ignition zone, while very important, is a recipe for more burned homes and towns.

          • I’d be interested in research supporting that last sentence. Are there examples of focusing only on home ignition zones? In Sharon’s example, do we know that the Borger prescribe burn would not have worked if it were only in the HIZ? (I suspect there are practicality limits to burning in the HIZ, and that treatments there would be mechanical removal, but has it been demonstrated that such treatments would not be sufficient?)

            • Jon, are you talking about a prescribed burn that focused on 0-200 feet from houses (the HIZ?) …? And what does “mechanical removal” mean in people’s backyards (?). Again, people would prefer that wildfires not go through their communities if it can be prevented from doing so. Here’s a link to a street view..,-101.3878427,3a,15y,268.49h,91.67t/data=!3m6!1e1!3m4!1sTlHy11xiemDdtDfAHEY0_g!2e0!7i16384!8i8192?entry=ttu

              • I’m talking about people taking responsibility for themselves by getting rid of the fire hazards in the HIZ on their property before they ask for help from the government. And I agree with Jim (below) that the priority for that help should be to move outward from the property to be protected. And I would add that property to be protected should prioritize homes. And again, I think there are enough high priority areas that we won’t need to talk about fuelbreaks in the backcountry for along time.

                • Ahh.. I feel like I’m back in the Regional Office 2010 ish, talking to profs from CU.. where are these “fuelbreaks in the backcountry”? please name some projects.. and then we can see the rationale in their NEPA documentation. In Colorado, they might also be protecting watersheds.

                  • I pretty much only pay attention to projects that get to litigation, but we’ve read a lot about “splats” and whatnot the last few years – are they just hypothetical? I suspect the two recent cases on the Los Padres are not in the WUI. The rationale I would be interested in is why they are a higher priority than untreated areas in the WUI. (I would wager that just about any project in the backcounty these days is based at least partly on fuel reduction.)

        • My point was that the Borger prescribed burn that protected the community was not in the HIZ, your diagram confirms that.. what point were you trying to make? I think the “HIZ only” ship has sailed (or wildfire equivalent?)

  3. Not just grasses, the encroachment of eastern red cedar is also driving earlier and earlier wildfire seasons in Republican counties. Because this is how red states finance infrastructure improvements while whining about Big Government. Ag producers have destroyed shelter belts to plant industrial crops that deplete aquifers and drought blows toxin-laden topsoil into downwind states. Spring wildfire seasons begin in eastern Colorado, western Kansas, the panhandles of Oklahoma, Texas and other Republican-held areas every year where moral hazard and poor ranching practices routinely decimate the high plains.

    • Spring wildfire seasons also occur on the Front Range of Colorado that is Democrat dominated. And don’t forget New Mexico! Which has very cool historic and other fire maps.
      PS I frequent part of western Kansas. What I have seen is old shelterbelts have died off, some have not been replanted. They grow wheat and milo (are those “industrial”?) and graze cattle.
      Interestingly I found an Ag Exp Station bulletin from 1927 (before the Dust Bowl) from Garden City.

      Experiments in dry-land farming have been conducted at that station since 1909.
      The average annual precipitation for the 18-year period, 1908 to 1925, inclusive, was 18.23 inches.
      The sorghums were the most consistent producers of grain and feed of any crops grown.
      Winter wheat produced a fair yield when grown under good methods of farming.
      Corn, spring wheat, oats, flax, and barley are unadapted except for a few local areas and for special purposes.

      A rational farming system for the Southwest includes the production of sorghums, winter wheat, and live stock. “

      The internet can be wonderful..

  4. Anti-forest management folks are always wanting to narrow the focus on individual issues, while ignoring the associated and important overall problems. They definitely never want to talk about silviculture and forest health, while accepting the current firestorm dangers, outside of private lands.

    Yes, there are people on the other side who insist that Overstory Removal is a key to all our forest problems, too. Timber volume should be a side effect of managing forests for multiple uses, including forest health and fire safety.

    My own keys to forest management are:
    1) Match forest densities to the CURRENT precipitation levels.
    2) Adjust species compositions to a more ‘natural’ state adding resilience and boosting ecosystem health.
    3) Adjust forest structures to a more ‘all-aged’ state, especially in former plantations.

  5. Logging for fue reduction, especially where canopy trees are removed, will stimulate the growth of grass and shrubs, thus exposing homes to greater threat of wildfire.

    Opening up the stand significantly will dry surface fuels due to increased light levels, surface winds and temperatures. This may increase surface fire intensity and rate of spread unless total surface fuel loading is reduced. In addition, thinning that allows significant light to reach the forest floor may result in the regrowth of small trees and shrubs, which over time become new ladder fuels.

    Stephen Fitzgerald and Max Bennett. 2013. A Land Manager’s Guide for Creating Fire-Resistant Forests. EM 9087. OSU Extension.

    • Hi 2nd.. I went to that link and it said:

      There are five principles of creating and maintaining fire-resistant forests:
      ■ Reduce surface fuels
      ■ Increase the height to the base of tree crowns
      ■ Increase spacing between tree crowns
      ■ Keep larger trees of more fire-resistant species
      ■ Promote fire-resistant forests at the landscape level By following these principles we can:
      ■ Reduce the intensity of a fire, making it easier for firefighters to suppress
      ■ Increase the odds that larger proportions of a forest will survive a fire (Figure 9). Small trees, shrubs, and other understory vegetation may be injured or killed, but larger trees in the stand will only be scorched, and soil
      damage also will be reduced
      ■ Reduce extent of post-fire restoration activities needed, such as replanting

      My bold… ????

      • Apparently we need to know the difference between “increase spacing between tree crowns” and “thinning that allows significant light to reach the forest floor.” So the evaluation of project effects should address how much light would reach the forest floor, and forest plans could specify an appropriate threshold for an ecosystem that would be “significant.” Let’s act like we know the best science and base decisions on that.

        • I tend to think that crown spacing should depend on the site-specific annual precipitation levels. Regular burning after treatments should help control the ladder fuel regrowth, until the crowns on the leave trees grow larger.

        • …. “increase spacing between tree crowns” and “thinning that allows significant light to reach the forest floor.”

          Much depends on the site, existing conditions, and desired future conditions. For example, on relatively dry sites in the west (ponderosa pine, etc.), both an increase in spacing between tree crowns and allowing significant light to reach the forest floor may be the intended result. Removing small and medium-size trees, leaving large scattered ponderosas and Doug-firs, mimics historic conditions on many sites. The grass and shrubs that take advantage of the additional sunlight and would burn (RX or natural fire) would burn frequently, without harming the larger trees. This is how forests around some communities in the west are managed — Bend and Sunriver, for example, where the USFS and local partners have done excellent work.

          • The article seems to assume that the opened understory might NOT burn frequently and could therefore burn more severely. But it is about the same eastern Cascades, so this is a little confusing.

          • Another thought – maybe the message here is (again) that only thinning + burning pays off in these habitat types, and if we’re not going to burn, we shouldn’t thin.

            • I contend that thinning projects remove/mitigate some of the fuels that burning would deal with. Remember, thinning isn’t just about fire safety (ad nauseum). Pretending that thick and unhealthy forests don’t burn is a fallacy.

    • Every potential treatment has some element of fire risk. Doing nothing is the biggest risk of all. Of course, 2nd always assumes that the Forest Service would attempt to harvest the maximum amount of trees possible. These ‘hit and run’ statements are just the same old stuff, in a different bottle.

  6. I don’t think “HIZ only” is effective in the long run, but it should be a priority in the short run. Likewise, mgmt efforts in WUI should be highly prioritized over those distant from urbanized areas. Similarly, removing sub-commercial ladder fuels should be prioritized over removing MOG. And btw, overstory removals really reduce crown fire incidents, but c’mon…


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