San Joaquin County, CA Tree Protection: Heritage & Protected Trees (2026)

San Joaquin County's Oak Woodlands Conservation Ordinance designates native oaks with a trunk diameter of 24 inches or greater at 4.5 feet above grade as heritage oaks, affording them enhanced protection. Removal of a heritage oak requires Planning Commission approval following a public hearing, an arborist-prepared Tree Protection and Removal Plan, CEQA environmental review (typically a Mitigated Negative Declaration or EIR for multiple trees), and mitigation at 5:1 to 10:1 (five to ten native oak seedlings or 15-gallon replacement trees per heritage oak removed) plus a 5-year maintenance bond. Construction adjacent to heritage oaks must respect the critical root zone (typically 1 foot of radius per 1 inch of DBH plus 5 feet), with tree protection fencing, no soil compaction, grade changes, or trenching within the root zone. Damage during construction — even accidental — triggers penalties, required remediation supervised by an arborist, and potential replacement obligations. Valley oak groves along the Mokelumne, Calaveras, and Stanislaus Rivers contain many heritage specimens. Stockton, Lodi, and other cities may have parallel heritage tree programs for urban trees.