First in the Knowledge-Sharing Arborist Insights Series

In 1982, Los Angeles County adopted the Oak Tree Permit (OTP) Ordinance to protect native oak trees and to preserve the ecological, historical, and visual character of the region. The ordinance required permits for projects that may remove or affect protected oaks and established one of California’s first comprehensive protected tree regulations. The OTP Ordinance set the benchmark for protected tree policy and became a model for other municipalities in California to establish their own protected tree ordinances. Other counties have oak protection policies which have been summarized by University of California Agriculture and Natural Resources. As one of California’s most influential protected tree frameworks, changes to the OTP Ordinance have implications well beyond Los Angeles County.

The state later expanded oak protections through the California Oak Woodland Conservation Act, which broadened protections from individual trees to oak woodlands. In 2011, the County adopted the Los Angeles County Oak Woodlands Conservation Management Plan to support compliance with the act. Together with the County General Plan, these policies continue to guide the preservation and long-term health of oak resources throughout Los Angeles County.

Now, the Los Angeles County Planning Department is updating the OTP Ordinance to streamline the permitting process, improve mitigation standards, and encourage early project planning with the intent to minimize impacts to protected oaks and help expedite permit approvals. In 2025, the County launched the update process and held eight public outreach meetings to gather stakeholder input. A draft updated OTP Ordinance is expected to be released for public review in 2026. This updated and streamlined ordinance may again become a model for other California local governments. Potential changes under consideration include:

• establishing minimum qualifications for Oak Tree Report preparers, such as American Society of Consulting Arborists Registered Consulting Arborist or International Society of Arboriculture Board Certified Master Arborist;
• allowing pruning for tree health without an oak tree permit, subject to site plan review;
• replacing the existing 2:1 oak tree replacement ratio with mitigation based on appraised tree value; and
• extending the mitigation monitoring requirements from 2 to 5 years.

Over the coming months, watch for additional updates on the County’s Oak Tree Program website to stay informed on how these proposed changes may affect your projects. To receive updates directly, you can sign up for notifications from the County.

Ascent’s Natural Resources team includes certified arborists experienced in protected tree regulations across California. Ryan Gilmore and Linda Leeman are happy to answer your questions about how these changes may affect your work. Stay tuned for additional articles in the Arborist Insights Series over the upcoming months, including updates on western Joshua tree surveys and permitting, hazard tree management, and funding opportunities through Proposition 4.