Across the United States, a seemingly harmless and ever-present plant is contributing to the rise of fast-moving, destructive wildfires. Grass, found in almost every environment, is increasingly becoming the fuel that turns small sparks into raging infernos. Unlike forests, where wildfires tend to be intense but slower-moving, grass fires can spread rapidly, overwhelming firefighting resources and destroying property in their path.
Fire experts explain that grass fires are less intense than forest fires but far more dangerous in terms of speed. Adam Mahood, a research ecologist with the U.S. Department of Agriculture, notes, “Name an environment and there’s a grass that can survive there.” Even in small patches of land, grass thrives, waiting for the right conditions to ignite. As a result, grass fires have become a leading cause of destruction, particularly in areas where homes are built closer to fire-prone wildlands.
A recent study revealed that over the last 30 years, the number of homes destroyed by wildfires in the U.S. has more than doubled. Surprisingly, many of these homes were not burned by traditional forest fires but by fast-spreading grass and shrub fires. The Western U.S. has been hit the hardest, with over two-thirds of destroyed homes located in that region. Of those, nearly 80% were burned in grass and shrub fires.
One factor exacerbating the problem is the increasing number of homes being built in the wildland-urban interface, where development meets fire-prone areas. As of 2020, about 44 million homes were located in these regions, a 46% increase over the last three decades. This growth not only puts more homes at risk but also raises the likelihood that human activity will spark fires in these vulnerable areas. Bill King, a U.S. Forest Service officer, explains that homeowners in these regions must be proactive in protecting their properties, as wind-driven fires can travel miles even with preventive measures in place.
Climate change is another driving force behind the rise of grass-fueled wildfires. In regions like the Plains, which are typically dry and windy, weather extremes have created ideal conditions for grass to thrive and burn. John Abatzoglou, a climate professor at the University of California, describes it as a “Goldilocks” zone—not too wet, not too dry—where grass can grow abundantly and ignite easily. Rainy springs encourage grass growth, but in winter, it goes dormant, turning into tinder for wildfires.
The Plains, in particular, have seen more megafires in recent years, such as the Smokehouse Creek Fire in Texas and Colorado’s devastating Marshall Fire, which destroyed over 1,000 homes. Grass dries quickly and becomes flammable within hours after rain, making it highly sensitive to weather conditions. With the addition of strong winds and invasive shrubs that burn hotter, grass fires can turn into widespread disasters in a matter of moments.
Grass also plays a role in the recovery and spread of fires in forested areas. When trees die from drought or previous fires, grass often invades, creating a continuous fuel source. Grass recovers from fire much faster than trees or other vegetation, sometimes reburning in just a few months, while forests may take years or decades to fully recover. This rapid regrowth makes grass a persistent threat in fire-prone areas.
In deserts, the rise of invasive grasses is creating new fire risks where they didn’t previously exist. Grasses like red brome have spread across the Mojave Desert, turning what was once a fire-resistant ecosystem into a fire-prone landscape. Recent fires in the Mojave have burned hundreds of thousands of acres, including iconic Joshua Trees, all fueled by invasive grass.
With increasing climate pressures, the prevalence of grass and its role in wildfire disasters will likely grow in the coming years. As Mahood puts it, “It may seem bad now, but this will probably not seem nearly as bad in the next decade.” The combination of changing weather patterns and invasive species is setting the stage for even larger and more destructive grass-fueled wildfires across the U.S.
