Portland Oregon has enacted a far reaching update of their regulations on protecting trees and their urban forest.  Originally slated to be effective in 2013 it will now be law as of January 1, 2015.

Here is the link to the current adopted  Portland, Oregon Title 11 Tree regulations as updated Jan 23, 2013 with an effective date of Jan 1, 2015. The link is to the Citywide Tree Policy Review and Regulatory Improvement Project Report  entitled Title 11 Trees  and includes the code language passed along with additional commentary on facing pages.

http://www.portlandoregon.gov/bps/article/350786

An earlier report by the Citywide Tree Policy and Regulatory Improvement Project is available also in a document entitled Recommended Draft Report to the Portland City Council  December 2010 details the issues and process that was involved in coming up with their new regulations.

http://www.portlandoregon.gov/bps/article/331401

Portland’s adopted regulations will now cover  trees on both public and private property including during development. As Portland explains in their ordinance it was enacted to:

“enhance the quality of the urban forest and optimize the benefits that trees provide. Desired tree benefits include:
1.Providing oxygen and capturing air pollutants and carbon dioxide;
2.Maintaining slope stability and preventing erosion;
3.Filtering stormwater and reducing stormwater runoff;
4.Reducing energy demand and urban heat island through shading of buildings and impervious areas;
5.providing visual screening and buffering from wind, storms and noise;
6.Sustaining habitat for birds and other wildlife;
7.Providing a source of food for wildlife and people;
8.Maintaining property values and the beauty, character and natural heritage of the city; and
9.Meeting the multi-purposed objectives of the Urban Forest Plan, including reaching and sustaining canopy targets for various urban land environments.”

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