Industrial-Area Street Trees in Portland, Oregon

"Industrial-area trees have, with few exceptions, been neglected by the research community as well as by urban forestry management programs. A recent project in Portland, Oregon, provides both some data and a program model that easily could be replicated in other communities. An inventory of the Northwest Industrial Neighborhood Association (NINA) district identified 966 street trees and 1,140 unplanted/potential street tree sites, for a stocking level of 46%. While this figure is low relative to most other segments of the urban forest, it was received optimistically because it was higher than had been expected for an industrial area and it demonstrated a great deal of potential for expanding the urban forest through additional plantings. Diversity data indicated only 17 genera were represented, identified two genera (Acer and Prunus) that were overplanted, and provided guidance on which genera could be added to increase diversity. NINA officials have formed a partnership with other local urban forestry interests and are using the data to undertake a 10-year planting program for the district."