The photo above underscores what street trees often have to suffer through.
With the trunk surrounded by concrete on all sides, the results are lifted pavements for pedestrians, and too little water for the tree. Amazingly, some people call for the offending trees to be cut down, but there’s a better solution.
Why not give the trees more space?
Marrickville Council is one council pursuing this policy. When a pavement comes up for renewal as part of the regular maintenance (planned five years ahead), a bigger opening is left for trees.
This gives the trees more space, and allows more rain to absorb into the ground, rather than into the stormwater system. I imagine it also saves a small (but measurable) amount of concrete.
Biodiversity is also increased when low plants, such as lomandras and dianellas, are planted around the base of the trees. With an even larger space, it becomes possible to establish a true verge garden.
Marrickville Council also goes beyond this. At the time of writing, the Sustainable Streets program enables residents to cut spaces out of their concrete verge for a small fee. If the majority of a street requests street gardens then the council will cut out the concrete, provide some extra soil, and even throw in some plants for free.
As a final note, this pavement work next to Petersham Park is another small but elegant example of the principle at work. Instead of re-laying the whole pavement with concrete, gravel was laid down for half the width. When I talked to the Council about this, they highlighted the benefits of less run-off, as well as providing more rain for the avenue of trees.
Councils have a big role to play in the sustainability of our local environment. If we can keep changing default policies to encompass environmental thinking, we’re well on our way to saving the planet!