Rangeland vegetation in California has evolved with a long history of fire. Reports from early Spanish explorers provide insight into Native American use of fire to maintain grasslands for hunting, oak tree germination and acorn production. Lightning also ignited natural fires, and the combination of the two created a mosaic of different age classes of brush with grasslands intermixed, creating natural fire breaks to minimize the spread of wildfire. Brush control by fire ceased in the 1980 's due to a range of factors including administrative barriers (permitting), environmental impact, and costs. While California's Mediterranean shrublands are ecologically adapted to periodic fire, identifying and adopting strategies to reduce the impacts of severe wildfires in shrublands is now key to reducing their destructive impact. One strategy is livestock grazing, an extensive land use (occurring on roughly 33% of land area statewide) that is also frequently adopted by State and local agencies as a fuel management practice. Shrubland ecosystems accounted for approximately 38% of California's burned areas from 2000-2020 but there is relatively little research into long-term management strategies to mitigate the impacts of shrubland fires. Livestock have been documented to browse on resprouts and slow the spread of shrubs; a management strategy that could reduce shrub encroachment. To understand shrublands' influence on fire intensity, we analyzed changes in land cover type resulting from major fires (based on hectares and structures lost). Results indicated that with no management, and depending on time and climate, shrublands quickly recovered, becoming the dominant vegetation type. However, while shrublands and grasslands fluctuate in extent, results indicated that forests are not recovering. Every fire footprint had similar changes, indicating that these vegetation patterns are not a feature of the most devastating fires only, but occur following any fire in land cover types that contain shrublands and forests.
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