Irvine Tree Trimming Rules (2026): What You Need to Know

Irvine's tree regulations reflect the city's master-planned character and commitment to maintaining a substantial urban tree canopy. The Zoning Ordinance Division 9 (Landscape Standards) and Municipal Code Title 5, Division 7 establish the framework for tree preservation, and the city's urban forest management program oversees implementation. Protected trees include any tree on public or private property with a trunk diameter at breast height (DBH — measured at 4.5 feet above the surrounding finished grade) of 10 inches or more, regardless of species. Heritage trees — those identified by the City Council for their age, size, species significance, or historical value — receive additional protection and may not be removed except under narrowly defined circumstances such as imminent hazard. All street trees planted within public rights-of-way are maintained by the City of Irvine Public Works Department and may not be trimmed, pruned, or removed by adjacent property owners without prior written authorization.

Property owners seeking to remove a protected tree must apply for a tree removal permit through the Community Development Department. The application requires identification of the tree species, a photograph, a site plan showing the tree location, and a written statement explaining the reason for removal. Acceptable reasons include verified structural hazard (confirmed by a certified arborist report), disease or death of the tree, or infrastructure conflict that cannot be resolved through alternative measures such as root barriers or selective pruning. The city arborist reviews applications and may conduct a site visit. Approved permits typically include a condition requiring replacement planting at a ratio of 2:1 (two new 24-inch box or larger trees for every protected tree removed), or payment of an in-lieu fee into the city's urban forestry fund if on-site planting is infeasible. The replacement species must be selected from the city's approved street and landscape tree list.

Routine maintenance pruning that removes no more than 25 percent of the living canopy in a single growing season generally does not require a permit, but all pruning work must comply with ISA pruning standards (ANSI A300). Topping — the indiscriminate reduction of the tree's height by cutting branches to stubs — is expressly prohibited on all trees throughout the city and constitutes a code violation regardless of whether the tree otherwise qualifies as protected. Lion-tailing (excessive removal of interior branches) is also discouraged. Property owners hiring tree service contractors should verify that the contractor holds a valid California Contractor's State License Board C-27 (Landscaping) or D-49 (Tree Service) license and carries appropriate liability insurance. Many Irvine neighborhoods have HOA landscape committees that impose additional tree-trimming requirements beyond the municipal code; residents should check with their HOA before performing any tree work.