Pima County, AZ Tree Protection: Tree Ordinances (2026)

Pima County's tree and plant protection framework encompasses multiple code sections. Chapter 18.72 (Native Plant Preservation) applies to all land-disturbing activities requiring a county permit. Chapter 18.67 (Watercourse and Riparian Habitat Protection) protects native trees and vegetation within designated watercourses, riparian habitat areas, and important riparian areas (IRAs). Development within buffer zones of washes and riparian corridors requires enhanced plant preservation. The Sonoran Desert Conservation Plan (SDCP) guides land-use decisions affecting native habitat. Pima County also administers the Conservation Lands System, which classifies land into biological core, important riparian, and multiple-use categories with varying levels of plant protection. Native trees along desert washes -- including velvet mesquite, blue palo verde, and desert ironwood -- receive additional protection through riparian habitat regulations. The county arborist or biologist may be required to review development proposals in sensitive areas.