Does Cattle Grazing Reduce Fire Fuels and Fire Danger?
The widespread and severe wildfires in California during the past several years highlight the importance of understanding how land management practices such as cattle grazing affect wildfire risk. The California Cattle Council recently funded a UC Cooperative Extension project to evaluate how much fine fuel (grasses and other plants) are eaten by cattle on rangelands, and how this may affect wildfire behavior. These results have not yet been published, but preliminary results are presented here.
Cattle Numbers
The study found that about 1.8 million beef cattle grazed California’s rangelands, which include grasslands, oak woodlands, and shrublands, in 2017. Beef cows were by far the most abundant beef cattle class, with 677,000 on range in the state. This was followed by steers, heifers, and bulls.
Fuel Removal by Cattle
Beef cattle are found grazing in every county in California, except San Francisco and they consumed 11.6 billion pounds of fuel in 2017. Our analysis which was based on county crop reports, Agricultural Census data, and UC Cooperative Extension data showed that cattle consumed vegetation across about 19.4 million acres of rangeland, primarily privately-owned. However, some grazing also occurs on federally-owned and other public lands too, especially in the mountain and desert regions of the state.
The amount of fuel consumed per acre varied greatly based on region (Figure 1). The average amount of fuel removed across grazed rangelands in the state was 596 pounds per acre. This number varied from 174 pounds per acre in the southeast interior region to 1020 pounds per acre in the San Joaquin-Sierra Region (Figure 2).