Over the past twenty-five years, in California, 4.5% of tree cover loss occurred in areas where the dominant drivers of loss resulted in deforestation, according to Global Forest Watch. In California, the top 9 regions were responsible for 52% of all tree cover loss between 2001 and 2024. Siskiyou had the most tree cover loss at 325 kha compared to an average of 52.5 kha. Deforestation in California occurred mostly because of drought, wildfires, and diseases.
California is the number one state that has lost the most trees. Over the past five to ten years, Ancient redwoods, sequoias, and Joshua trees have been lost to wildfires, drought, and disease. Over the past eight years, California has experienced five of the most destructive wildfires in its history: the August Complex Fire (2020), Camp Fire (2018), Dixie Fire (2021), Mendocino Complex Fire (2018), and Woolsey Fire (2018).
The August Complex Fire in 2020 is the largest wildfire in California history. It burned 1,032,648 acres across six counties (Glenn, Lake, Mendocino, Tehama, and Trinity). This was sparked by lightning in the Mendocino National Forest, and it took firefighters 87 days to contain. While no civilians were killed, one firefighter lost their life battling the flames.
In late 2024, wildfires occurred in Malibu and Los Angeles. The California Department of Forestry and Fire Protection estimates that more than 16,200 structures have been damaged or destroyed in the Palisades and Eaton fires. At least 29 people were killed in the two fires: 17 in the Eaton Fire and 12 in the Palisades Fire. This led to the aftermath of many people losing their houses and experiencing extreme air pollution.
California converted over 1.2 million acres of farmland from 1984 to 2018 into urban uses at a rate of about 36,500 acres/year, roughly one square mile every five days. In counties like San Bernardino, Riverside, Fresno, Sonoma, and Contra Costa, especially heavy losses occurred according to the California Department of Conservation. This destroys biodiversity, and farmers lose access to fertile land, while real-estate developers, the government, and agencies profit from urbanization.