A research team based in California is studying how cattle grazing can lessen the severity of wildfires on rangeland across the West.
Devii Rao, of the University of California Cooperative Extension, gave a presentation summarizing the preliminary results during a panel discussion Oct. 15 hosted by the California Climate and Agriculture Network, or CalCAN.
“This is really an issue we are starting to look at for how we can deal with these large fires,” said Rao, a livestock and natural resources specialist working with producers in San Benito, Monterey and Santa Cruz counties.
CalCAN is a nonprofit coalition of sustainable and organic farming organizations that advocates for state and federal policies to improve climate resilience.
The panel was part one of a series of webinars focused on agricultural solutions to wildfire. Part two will be in November, exploring the role of prescribed burning.
Rao, who is also co-chair of the Central Coast Rangeland Coalition, said the state had roughly 1.8 million head of cattle — mostly beef cows — grazing 19.4 million acres of public and private rangeland in 2017, according to the USDA.
The team estimates the animals consumed 11.6 billion pounds of vegetation, or 596 pounds per acre, ranging from 174 pounds per acre in the arid Southeast Interior Region to 1,020 pounds in the San Joaquin-Sierra Region.
Grasses and other fine fuels can contribute the size and intensity of rangeland fires. The key, Rao said, is flame length. If flames are shorter than 4 feet, crews can typically battle fires on the ground using hand tools.
Flames 4-8 feet tall usually require heavy machinery such as plows and bulldozers to contain the spread. At 8 feet or taller, Rao said it becomes no longer safe for firefighters on the ground, and air support is required.
The study uses modeling to determine what forage density is required at different wind speeds, fuel moisture and slope to keep flames below 8 feet.
For example, Rao said a fire on flat ground with 2% fuel moisture and 15 mph winds could not have more than 686 pounds of forage per acre.
That number drops to 214 pounds per acre as wind speed increases to 40 mph, which is lower than state guidelines for residual dry matter needed to control other disturbances like erosion and invasive species.
While managing with livestock does raise some potential conflicts, doing nothing can be just as harmful, she said.
“I think we need to consider those tradeoffs and recognize that, with no management, it can be just as damaging if not more damaging than other options,” Rao said.
Other participants on the CalCAN panel included Andree and Bianca Soares, of Star Creek Land Stewards based in Los Banos, Calif. The company uses sheep and goats to provide vegetation management for public and private landowners.
Despite their success, Andree Soares said they face several challenges, from California’s agriculture overtime rules to maintaining a workable H-2A visa program. Most of their herders come from Peru.
Soares said local ordinances must also allow grazing inside city limits to maximize the benefits.
That is where Marc Horney, a professor of rangeland resource management at Cal Poly, comes in.
Horney is chair of the California Board of Forestry and Fire Protection’s Range Management Advisory Committee. He said the group has promoted targeted grazing at the state and federal level to increase awareness of the benefits.
Horney said California and other Western states need to come up with fire management plans that address fuel loads. Targeted grazing, he said, can be part of the equation.