Street Trees

In July 2020, Council invited Michael J. Mills, a consulting arborist with more than 25 years experience, to present on an improved method for establishing decorative street trees.

Mr. Mills had originally been contacted by Town staff in relation to two trees on the south side of Gower Point Road, which had outgrown their planting sites and were pushing up the surrounding sidewalk in an effort to find water, oxygen and nutrients. This was causing an extreme tripping hazard for pedestrians.

While staff’s goal had been to save the trees, which were planted about 30 years ago, it was determined that this was not possible.

It was also determined that when new trees were planted, a better method would be employed.

Healthier Root Systems = Healthier Trees

Rather than individual tree pits, as was used in the past, this planting method involves building a linear trench below the sidewalk. The trench is then filled with “structural soil”, which is a blend of soil and angular aggregate. (See photos and diagram below.)

This system provides a firm foundation for the sidewalk, while creating a much larger space for the trees’ root systems. This leads to happier and healthier trees.

On April 19, 2021, the two root-bound trees were removed and work to build a linear trench system was begun.

Red Rocket Maples will be planted at the site, which have been chosen for their narrow and upright form. They should be in place by early May 2021.

 

1. A large linear trench is created below the sidewalk.

 

2. The trench is filled with structural soil – an engineered mix of soil, rock and binder.
3. Trees are planted and the sidewalk is laid. Tree root systems share the space created by the trench, rather than being limited to an individual pit.