An alternative to planting in the sidewalk along the curb line is to utilize the "Back of Sidewalk" program.
The "Back of Sidewalk" program is designed to plant new street trees in an environment that is more conducive to sustained growth. The improved growing environment provided through the "Back of Sidewalk" program will result in improved long-term health of the newly planted trees.
The purpose of the "Back-of-Sidewalk" program is:
- To expand the diversity of street tree species
- To provide trees where few exist now
- To extend the average life of new trees by planting them, where feasible, behind the sidewalk on private property
"Brookline has thousands of beautiful trees on its public highways and private estates, and its citizens may well be proud of them."
Emma G. Cummings, Brookline's Trees, 1938.
Increasing the diversity of Brookline's street trees reduces the risk of blight (such as Dutch Elm disease), and provides a more varied look to each street. Species that have been planted include Japanese maple, magnolia, sweetgum, weeping cherry and Korean Mountain ash. Criteria for species selection include the size of the house, the width of the street and the existing tree species on the street. Because this program serves primarily to enhance the streetscape, the tree must be completely visible from and planted within 20 feet of the sidewalk.
In urban areas, opportunities to plant new street trees are often limited to small cutouts in the sidewalks called tree pits. This type of tree pit planting stresses a newly planted tree for many reasons. These include a restricted area for root growth that restricts the uptake of water and nutrients, higher temperatures in the summer due to the surrounding cement and asphalt, impacts by road salt in the winter and soil compaction in the spring, summer and fall. While trees are amazing plants, this type of growing environment is a difficult spot for trees to establish new root growth for the long term.