Evanston, IL Tree Protection: Protected Tree Species (2026)

Section 7-8-8-4 sorts every tree species in Evanston into four groups, A through D. Group A holds the highest-rated and most valuable trees, and Group D holds the lowest-rated trees, the ones that provide the fewest desirable ecosystem and community benefits. The species lists sit in the City's Tree Canopy Preservation Policy, which the City posts on its website and keeps in physical form at the City Clerk's offices.

Protection starts at a minimum DBH, the trunk diameter in inches. All public trees are protected at 2 inches. Trees in Group A, Group B, Group C and Group D are each protected at 6 inches. Subsection C then closes the loop: a tree with a DBH below the minimum is not a protected tree. The chapter's definition of a protected tree simply points back to this section, so these thresholds control every other rule in Chapter 8.

Multi-stemmed trees have their own rule. If the tree has a multi-stemmed trunk system and a maximum height under 20 feet, the City uses the single largest trunk, measured in inches at a point 4.5 feet above the existing grade at the base of the tree. If the tree is taller than 20 feet, the DBH of all trunks is added together, so a cluster of modest stems can still cross the 6-inch line.

Protected status is what triggers the rest of the chapter. Under section 7-8-8-5, any activity within 25 feet of a protected tree's trunk is a regulated activity, as is construction, earthmoving, demolition or vehicular traffic inside a protected tree's critical root zone. Those activities need a tree preservation permit from the City Manager or designee, who has 14 days to request more information or issue the permit. Removing a protected tree when no regulated activity is proposed is not permitted without a variation from the Human Services Committee and City Council, and removal brings a replacement or mitigation requirement set by the tree's group and DBH under section 7-8-8-7.