The recent abnormally hot catastrophic wildfires including the historically large megafire that devastated southern California (Thomas, Sonoma etc.) in and around the wildland urban interface (WUI) and forests today are initially and substantially fueled by the now excessive annual grasses and brush.
There is extensive scientific research that explains the reason why these prodigious amounts of grasses and brush, also known as ground fuels, have evolved recently. Under recent historic conditions in and around forests and grasslands, deer had kept the ground fuels under control, which significantly mitigated wildfire frequency and severity; but that has changed. Research shows that whenever a herbivore population is depleted, catastrophic wildfires take over, to wit:
According to Science Magazine: “By altering the quantity and distribution of fuel supplies, large herbivores can shape the frequency, intensity, and spatial distribution of fires across a landscape. There are even unique interactions among large herbivore populations that can influence fire regimes. For example, facilitative interactions between white rhinoceros and mesoherbivores result in reduced fuel loads and fuel continuity, and consequently fewer large, intense fires. Other factors can influence the frequency and intensity of fires, particularly in locations where the total area burned is strongly related to ungulate population size.”
The problem today is simple; the ecosystem is out of balance. For instance; on average a single deer will consume about 7 pounds of grasses and brush daily. Considering the deer population depletion in California of about 2 million deer (net loss) over the past few decades, the loss in ground fuel abatement (grasses and brush) in and around forests amounts to roughly 18 million pounds of fuel per day. Annually, this amounts to roughly 2.5 million tons of grass and brush that is no longer being abated by natural means, just in California alone.
Of course some people who benefit financially or politically from the livestock industry believe that livestock are the answer to all of mankind’s and nature’s ills. This same thinking suggests that livestock can generally be used for grazing these excess ground fuels. But that thinking is what has brought us to the brink of destruction by catastrophic wildfire and trending deforestation through policies posited by those on the other-end of the spectrum: the ‘let it burn’ environmentalists. Neither extreme has it right, and the appropriate solution is available but has been intentionally dismissed or overlooked because of the typical downfalls of man: greed, ego and ideologies.
Recently, a reader who is a professional firefighter for the Oregon Department of Forestry sent me an email that posed the following important question: “One article I came across troubled me slightly. I can’t recall who it was written by but it stated that wild horses changed the fire regime of the area by consuming the natural grasses and allowing the invasive species to become dominate and increase fire spread rates (more I think for the area they were referring to). Do you know of any studies done on this if so can you refer them to me.”
I immediately recognized the statement (wild horses adversely affecting wildfire regime) as one of many canards that have been spun by some folks in and around the livestock industry along with some researchers. In reality the opposite is true; livestock grazing adversely affects and depletes native pastures and worsens the fire regime.
First, let’s get the number one livestock industry canard dispelled. The truth is that American wild horses are without any doubt a native species. And the best science tells us that here.
More comprehensive information about that myth and others here: The Three Greatest Myths About American Wild Horses.
Invasive species grazing by cattle, sheep and goats, all of which are not North American species, adversely affects wildfire regimes on native pastures, especially in and around wilderness and fragile forest areas.
North American ecosystems