Riverside County, CA Landscaping Rules: Tree Trimming (2026)

Routine residential tree trimming is not subject to permit in most of unincorporated Riverside County. Ordinance 461 authorizes Transportation to require trimming of vegetation that encroaches into the road right-of-way, obstructs sight-distance triangles, or interferes with signage. Utility companies (SoCal Edison, Imperial Irrigation District, Anza Electric) trim under CPUC General Order 95 clearance rules regardless of owner preference. Under Public Resources Code §4291 and Ord. 787, WUI property owners must trim tree limbs within 10 feet of chimney outlets, remove dead branches overhanging roofs, and maintain ladder-fuel separation from ground vegetation. Native oak woodlands within Multi-Species Habitat Conservation Plan (MSHCP) areas have protections that may trigger biological review before heavy trimming or removal. In scenic highway corridors, heritage-tree trimming may require advance notice. Neighbors may trim branches overhanging their property up to the property line (California common law), but cannot enter the other owner's property to do so and are liable if the trimming kills the tree.