Learn About the Opportunities and Challenges Facing Sammamish’s Urban Forests

Release Date: July 11, 2018

The City of Sammamish Urban Forest Management Plan (UFMP) team is pleased to introduce the UFMP Storymap, an exciting and interactive new tool that can help community members understand the strengths and benefits of our urban forest, as well as the opportunities and challenges that it currently faces.


The UFMP Storymap includes data and interactive maps that show information about current urban forest conditions in Sammamish including urban tree canopy data analyses and findings and recommended actions the City and residents can take to achieve citywide urban forest management goals. Highlights of the Storymap include data from a recent canopy cover study completed by the UW Urban Ecology Research Lab. According to the study, 48% of Sammamish is currently covered by tree canopy, while 25% of the city is covered by impervious surfaces (roads, buildings) that repel stormwater and contribute to heat island effects. The remaining land in the city is pervious areas of low vegetation such as understory (11%), bare soil (2%) such as athletic fields, and open water (2%).


To put this data in context, our neighboring cities have the following canopy cover:


Issaquah (2006) - 51%

Snoqualmie (2011) - 44%

Kirkland (2010) - 41%

Seattle (2016) - 28%


The Storymap also illustarates the health of Sammamish’s canopy cover. Using the citywide tree canopy data, a relative health assessment established a benchmark that over 75% of the urban tree canopy could be in Good and Very Good health. Almost 14% was classified as in Fair health, and approximately 9% of the canopy is in relatively Poor health or Dead. Trees growing in an urban environment can face many challenges: poor soil quality, restricted rooting area, air pollution, increased temperatures, construction damage, vehicular accidents, soil compaction, drought stress, and stress-induced insect and disease infestations. Of particular concern for Sammamish are remnant issues from its logging history, including specific concerns over Laminated Root Rot and other diseases affecting native trees.


The full version of the UFMP Storymap including information about forest fragmentation, health, public trees, and forest management is available online at: http://bit.ly/SammamishStoryMap. More information on the development of the Urban Forest Management Plan and next steps is available on the City website at http://bit.ly/SammamishUrbanForestPlan.