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Check out the street tree map

Screenshot of the street tree map

Have you ever wondered about the type of tree in front of your house and whether you are supposed to take care of it?  Have you been curious about a certain species of tree or wondered whether it grew in your neighborhood? There is a new way to answer these questions, because for the first time ever, SDOT has published an interactive street tree map!  Here is the link: . The map reveals species, maintenance responsibility, size class, diameter (if available), tree identification number, date it was added to the inventory, and the date the information was last updated, if available.  Over 122,000 street trees are in the inventory, making this a great tool to learn about your urban forest.  SDOT GIS Analyst, Dana Trethewy developed the map based on existing web-based maps, such as the pothole map. 

The maintenance responsibility of individual street trees is determined by the entity that planted it.  If a homeowner or a volunteer group planted the tree, the abutting property owner must maintain it.  If the Seattle Department of Transportation planted the tree, we are responsible for maintenance.  Street trees that are on Parks Department boulevards or adjacent to parks are the responsibility of the Seattle Parks.  On the map, maintenance responsibility is represented by color—different shades of green indicate responsibility.  Heritage trees, both in the right-of-way and on private property, show up on the map in orange.  For more information on heritage trees, here is an article:

The map isn’t perfect.  The data is taken from SDOT’s street tree data, first collected in 1991. In 2007 SDOT-maintained trees, which account for 40,000 of the City’s street trees, were comprehensively updated.  New trees planted by SDOT are routinely added to the inventory.  Privately-maintained trees have not been updated since the 1991 inventory; if they were planted after 1991, they are probably not on the map.  If the information on a particular tree has not been updated, the diameter is null, as it is likely that the 1991 data is no longer correct.  If a tree is not in the inventory, it is most likely privately-maintained.  There is a form you can fill out to request tree additions.  Emailing a photo of the tree(s) helps.  The “contacts and links” section at the right of the tree map has links to request forms for adding a tree to the inventory.     

When you first open the map, click the check box for “public right of way trees” to view all street trees. To identify a single tree, zoom in until you can see individual property parcels.  Click on a tree to display its information.   You can search for a particular address or a neighborhood.  You can also search for a species of tree, by entering either the common or scientific name for the tree, and clicking find trees. The trees of that species will appear with a blue square around them.  There are currently some bugs in the species search, but our GIS expert is working on it. More information is available under the tab “How to use this map” at the right side of the page.  Have fun exploring the urban forest!