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 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.