Lincoln, CA Tree Protection: Protected Tree Species (2026)

Lincoln sits in the Sacramento Valley oak-woodland ecotone, and the City's development review process requires applicants to identify and inventory every native oak on a project site, consistent with the format in the City's Appendix F Arborist Report and Native Oak Tree Inventory template. Native oaks of concern in the area include blue oak (Quercus douglasii), valley oak (Q. lobata), interior live oak (Q. wislizeni), and coast live oak (Q. agrifolia). California Public Resources Code Section 21083.4 defines an 'oak' as a native tree species in the genus Quercus, not designated as commercial Group A or Group B species under State Board of Forestry rules, that is five inches or more in diameter at breast height; under CEQA, counties (and cities acting as lead agencies) must determine whether a project may convert oak woodlands with a significant environmental effect and require mitigation. In February 2025, the Placer County Board of Supervisors approved a conservation acquisition of blue oak woodlands north of Lincoln, underscoring the regional priority on blue oak habitat. Lincoln does not extend categorical protection to non-native species (e.g., privately planted palms, eucalyptus, ornamental fruit trees), though all street trees in the right-of-way remain regulated under Title 12 and the Public Facilities Improvement Standards.