In the summer of 2009, the City of Somerville completed its first comprehensive public tree inventory, a full catalog of all trees in the public right-of-way. The inventory provides a detailed picture of the composition, health, and maintenance needs of Somerville's tree resources. It also offers rich baseline information that will guide city managers in their efforts to develop a forward-thinking Urban Forest Management Plan.
A preliminary analysis of the inventory data has revealed some key findings:
- There are 11,404 tree sites located in the public right-of-way;
- There are 244 open tree wells that are potentially available for future tree plantings;
- Citywide, there are 4.3 public trees per acre of land and 1.4 street trees per 100 feet of roadway;
- Somerville's current tree stock comprises 101 species and 52 genera (or groups of species that share similar characteristics);
- The ten most frequently occurring species are: Norway maple (22%), callery pear (16%), red maple (11%), thornless honeylocust (9%), green ash (9%), littleleaf linden (8%), Japanese zelkova (4%), London planetree (3%), Japanese flowering cherry (3%), Japanese tree lilac (2%);
- The ten most frequently occurring genera are: maple (32%), pear (14%), ash (9%), honeylocust (9%), linden (8%), sycamore (4%), zelkova (4%), oak (4%), cherry/plum (3%), and lilac (2%);
- 2,801 trees (25% of the total population) are rated in "Good" condition; 6,389 (58%) are rated in "Fair" condition; and 1,777 (16%) are rated in "Poor" condition;
- There are 95 dead trees;
- 64% of the inventoried trees require some kind of routine maintenance (e.g., pruning or trimming); 8% (approximately 860 trees) are recommended for removal;
- The total estimated value of Somerville's public trees is approximately $15.9 million; and
- The total estimated value of each individual tree is approximately $1,400. (Note: This conservative valuation is based on a standard formula developed by the Council of Tree and Landscape Appraisers and found in the Council's Guide for Plant Appraisal (9th Edition). The City of Somerville will conduct more detailed cost-benefit analyses of its inventory data in the late 2009 and early 2010).
For a more in-depth analysis of the inventory data, please see the City's Draft Urban Forest Management Plan.
Public Access to Inventory Data
The City of Somerville is using web-based software called TreeKeeper ® 7 to manage its tree inventory data.
Recognizing that the inventory may have many applications for residents, community groups, and businesses, the City allows guest access to the TreeKeeper system. Though this access is limited to "read-only" privileges, guests can still search and view all of the data currently available about Somerville's public trees.
To access the TreeKeeper system, simply go to http://somervillema.daveytreekeeper.com/, and then click "Guests Click Here to Login."
For technical assistance using TreeKeeper, please use the online "Help" function. If you continue to experience difficulty, please contact the Urban Forest Initiative Program Manager for further assistance at 617-625-6600 x2500.