Lexington Tree Inventory, 2004 to 2010

The Lexington Tree Inventory is a collaborative effort of:

• The Lexington Tree Committee
• Urban Ecology Institute (UEI) of Boston College and Tufts University
• Lexington's Department of Public Work Divisions of Public Grounds and Engineering and
• Department of Information Technology

Volunteers and summer college interns from Clark University, Northeastern and Brandeis Universities, supported by grants, have counted approximately 6,000 street trees and completed 6 out of 9 Lexington precincts. This is approximately 65% of Lexington's streets.

Lexington's Major Street Tree Species

• Norway maple - This is the most populous and is an invasive species. The Norway maple was planted as a hardy street tree to replace the dying American elm, before its invasive properties were understood.
• Red oak - native species
• Red maple - native
• White pine - native
• Sugar maple - native
• 'Mixed groves' - These are found in minimally managed roadside areas and contain different species of trees.
• White ash - native
• Callery pear - This non-native species has invaded both Lincoln Park and Belfry Hill.
• Black cherry - native
• 'Other' - The large size of this category indicates the wide diversity of species in Lexington's tree population.

Data Collection

Data is collected using handheld computers. Interns documented their computer procedures. They developed a system to count trees in minimally managed areas by grouping them in 'groves' rather than locating each individual tree stem. This is a technique that made counting roadside areas efficient.

Lexington's tree population is primarily healthy.

Summary of State of Town Tree Health:

• Good: 79%
• Fair: 15%
• Poor: 6%
• Total: 100%