Sydney’s Sutherland Shire trialling Citygreen® tree pit systems in community projects
An upgrade to the Engadine shopping centre in Sydney’s Sutherland Shire has employed Citygreen’s RootCell structural modules and RootDirectors to give the best growth prospects to new trees while also protecting the pavements from root intrusion.
The Shire Council is now specifying the root protection systems for other tree planting projects in the area, including a major town square development in Engadine.
RootCells provide rigid structural space filled with healthy soil for the roots to grow into, preventing them being compressed by traffic above and ensuring the roots receive vital nutrients, including water and oxygen. This gives the new trees the best chance of healthy life in the city environment.
RootDirectors prevent the root systems of growing trees from intruding into footpath or roadway substrata and eventually buckling the paved surface.
Engadine’s new street trees are being irrigated by an innovative roof drainage system that catches rainwater from the verandahs of shops along Old Princes Highway in the commercial centre of Engadine.
The streetscape upgrade also included new footpath paving, garden beds, seating, lighting and waste bins.
“The trees have been in for two years on one side of the street and one year on the other side, although they’re too small yet to tell if the roof watering system has helped the trees or to judge the protective value of their root containment systems,” said Andrew Urio, landscape architect, Sutherland Shire Council.
“The shopping centre upgrade was the first time we had used Citygreen’s RootCells and RootDirectors. Since then, we’ve be
gun to specify them for other projects within the Shire.”
The streetscape improvements at Sutherland Shire have been a collaborative team effort among the council’s civil engineers and landscape architects.
Supplied by Citygreen Australian distributor – Arborgreen Landscape Products – these RootCells and Root Directors have also been installed in the Engadine Town Square development, just completed at the junction of Old Princes Highway and Waratah Road.
In a fully paved area, there are eight new trees that are receiving water from the roof of the adjoining community centre.
“We’re using 3.3 m x 3.3 m RootCells – as big as we can – to give the best results for the trees being watered by the new community centre,” Mr Urio said.
“RootCells have become our typical product to include in pathwork in our urban area – for example, in a pavement upgrade and tree planting in front of the council library in Cronulla.
“These projects are allowing us to assess the functionality of RootCells and Root Directors, as opposed to alternatives we’ve used before for tree and pavement protection, including structural soils.
“We’re looking at the long-term value added to projects over a five to ten year assessment period. This includes the preservation of pavements as well as the health of the trees,” he said.
Many arborists and landscape architects are now recognising that the modular, structural soil cells represent current best practice for trees in cities.
For more information, visit www.citygreen.com/ or send an email to info@citygreen.com/