Title 11 Code Amendment Projects
2022 Technical Amendment Project: Complete
2024 Large Tree Amendment Update: Complete
2026 Title 11 Amendment Project: In development
Title 11 Administrative Rules Under Development
PRK 2.07 Reduced Minimum Tree Planting Size (effective November 1, 2025)
PRK 2.07, A New Administrative Rule Allowing Younger Trees to be Planted
Background
The Tree Code (Title 11) sets minimum size requirements for trees which require a permit to be planted or are planted as a condition of a permit. This minimum size standard applies to all street and City trees and trees on private property which are required as mitigation for tree removal or as part of property development. These standards are detailed in Tree Planting and Specifications (11.60.020). These size requirements have been identified as a potential barrier to complying with Title 11, expanding citywide tree planting programs, and contractor development efforts.
What is PRK 2.07?
PRK-2.07 is an administrative rule to reduce the standard size requirements for tree planting in situations when there is no associated development. This rule allows younger trees to be planted in certain situations. This rule is being pursued to support established City goals to preserve and equitably expand Portland’s urban tree canopy.
Changes
The administrative rule reduces the size requirement for broadleaf trees planted on-site from 1.5 inches to 0.5 inches caliper. The rule reduces the size requirement for coniferous trees planted on-site from 5 feet to 3 feet in height. On-site trees include trees planted on private property or on City property, excluding the right-of-way.
The rule also sets the broadleaf street tree requirement at 1.5 inches caliper for all zoning types. It does not change the minimum size requirement for coniferous street trees.
The rule only changes tree size requirements in situations not associated with development. The standards set by 11.60.020 and Table 60-1 in the Tree Code would still apply in private development, associated public works, and capital improvement projects.
Timeline
PRK 2.07 took effect on November 1, 2025 and lasts until the end of June 2028. After this trial period, the effectiveness of this new rule will be assessed, and if it is determined to be effective and equitable, it may become permanent.
A full list of adopted Urban Forestry policies is available here: Portland Policy Documents