Protected trees
The city treats any tree not on its Prohibited Species List as a "Protected Tree" under UDC Section 5.2.3. Its permit form says trees 6 inches or more in diameter, measured 4.5 feet above grade, need a permit to be removed or harmed. Prohibited species include Callery pear, cottonwood, chinaberry, mulberry, silver maple, hackberry, Arizona ash, Chinese tallow, mimosa, Siberian elm, tree of heaven and honey locust.