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

Siskiyou County has no county-wide ordinance dictating how or when ordinary trees on private land must be trimmed for appearance. The trimming rules that exist are part of the wildfire-hazard chapter, Siskiyou County Code Title 3, Chapter 3 (Fire Control and Fire Hazard Regulations). Section 3-3.02.3 requires owners of buildings on mountainous, forest-, brush- or grass-covered land to remove the portion of any tree that extends within 10 feet of the outlet of a chimney or stovepipe, to maintain any tree adjacent to or overhanging a building free of dead or dying wood, and to keep the roof of any structure free of leaves, needles, or other dead vegetative growth. These requirements work alongside the broader firebreak-clearance duties in Sections 3-3.02.1 and 3-3.02.2. There is no county tree-topping permit or street-tree pruning ordinance for the unincorporated area; tree work for fire safety is the owner's responsibility. Where a tree is part of a defensible-space requirement, the statewide standard of Public Resources Code 4291 (100 feet of defensible space in State Responsibility Areas) also applies, and CAL FIRE guidance on vertical and horizontal spacing of tree canopies is used during defensible-space inspections. For trees within an electric utility's right-of-way, separate state line-clearance rules apply.