Urban Forestry staff at DNR recently attended the annual Urban Forestry Symposium in Seattle entitled, Climate Change and the Urban Forest. It was an excellent day of learning, with great speakers reporting the newest information about issues affecting trees in urban forests of the Pacific Northwest.
Nick Bond, a Washington State climatologist, reminded us that seasonal fluctuations are normal; however, he also pointed out that he is observing an overall trend in rising temperatures in the Pacific Northwest. Models indicate longer, wetter, cooler winters and dryer, hotter summers. Most healthy, well-established trees will be able to withstand these changes over the course of their lifetime. It’s the newly planted and establishing trees that may find the going a bit rough, especially if those trees are selected from an existing palette of species that thrive in conditions more historically seen in our region.
Planning for trends expected in the future is an essential part of growing a sustainable urban forest. This might mean experimenting with new species from adjacent regions, those more southern, or drier, but good planning always involves selecting the right tree for the right place. Planning involves optimizing and designing planting sites to assure adequate soil volumes and above-ground space for long-term mature tree growth; space where a tree can grow to maturity and provide the expected benefits. Planning means thinking ahead in “tree time” in order to avoid conflicts between trees and infrastructure and maximize the lifespan and utility of both trees and other components of city infrastructure. Furthermore, planning includes a realistic evaluation of the cost of establishing healthy trees in the landscape. The benefits we expect from trees will not be realized unless trees are planted correctly, structurally pruned as needed, and protected from the damage that results in mortality.
See the article “Climate Change and the Northwest’s Trees” in this edition of the Tree Link for more information about the impacts of climate variability on our native forests.
DNRs Forest Action Plan recognizes that “there is a need to build climate change considerations into all project design elements.” (pg 44, Statewide Assessment & Strategy, Strategies Section) Give us a call. DNR’s Urban and Community Forestry program is here to help your community design a sustainable community forest.
By Linden J. Lampman
DNR Forestry Program Manager