Tigard, OR Tree Protection: Protected Tree Species (2026)

Chapter 8.10 of the Tigard Municipal Code, Trees in Sensitive Lands, is the part of Title 8 that protects trees by species in the City of Tigard. Section 8.10.020.A limits it to sensitive lands under City of Tigard jurisdiction described in Section 18.775.010.G, and the city maintains a map of sensitive lands that is accessible to the public. Under § 8.10.020.B the city manager or designee uses that map to decide whether a particular tree is within sensitive lands. A person who wants reconsideration must provide a delineation by a professional land surveyor conducted in accordance with all applicable agency accepted methods for the sensitive lands type in question.

Species come in through subsection C: only those native trees listed on the native tree list in the Urban Forestry Manual are subject to the chapter. The municipal code text does not print that list, so the species names sit in the manual adopted by administrative rule under § 8.02.040. The code separately defines a nuisance tree as any tree included on the Nuisance Tree List in the Urban Forestry Manual.

The protection itself has two parts. Under § 8.10.030.A, native trees of six-inch DBH or more, and native trees required as replacements, are maintained consistent with tree care industry standards and so as not to become hazard trees. Under § 8.10.040, no person shall remove any native tree of six-inch DBH or more, or any smaller native tree that was required to be planted as a replacement, without prior written approval through the City Manager Decision Making Procedures in § 8.04.020 or the City Board or Committee procedures in § 8.04.030, using the Sensitive Lands Tree Removal Standards. A native tree that dies within three years after planting is removed and replaced under the previous permit approval.

Separately, a significant tree grove is a stand of trees identified as significant through the Statewide Land Use Planning Goal 5 process, and the director of community development maintains a Significant Tree Grove Map.