This application was made using the city’s street tree inventory to show unique information about the trees owned and cared for by the city. OTTrees is a bird’s eye view of Ottawa; the trees displayed show foliage based on the season, the location, and the estimated spread of branches over the houses and buildings of the city.

OpenData sources used

Tree Inventory (Street Trees)

The value it provides to residents

Would you like to visit the oldest trees in the city? From the data assembled an estimate to how old the tree is can be based on the species, growth factor, and diameter of the tree at breast height. There is also an ancient tree bike route made from the oldest of of each species over 500 years old.

Would you like to see what streets to avoid in the springtime if you have allergies? The map displays trees that can generate mild to severe allergens. Want to walk down the best streets to appreciate the changing spring and fall colors? The trees paint a gorgeous cacophony of color throughout the city.

The application was written using Java, JavaScript, HTML, CSS, and Google Maps API v3; it is available free of charge. The source code is available on Github. When clicking on a list, please be patient! The data and calculations can take some time to load. Enjoy!


  1. Rebecca Aird

    The bike tour is a very cool idea but Eeeek! You must be confusing DBH with circumference. There is no 248 dbh 744 year old largetooth aspen in Ottawa (or anywhere else for that matter). Even a 300 year old tree of just about any species anywhere in Ottawa would be something to celebrate!

  2. Emily Daniels

    Hi Rebecca-
    The d.b.h. values are part of the data set given by the city. I do not know how the Public Works Dept/Forestry service collects the data but d.b.h. is determined by measuring the circumference of the tree and diving by pi at about 4.5 feet (1.37m) off the ground.

    Even though individual aspen live for around 50-60 years, they are part of a larger organism since multiple stems sprout from the same root system. They might be factoring this into the dbh for that tree.

  3. Matthew Hayley

    I like this application but the age calculations are off. A 700 year old street tree in Ottawa is not possible. However even without the age factor this app is a great use of the City's tree data.

Sign In or Register to comment.