Case Study – Coles Building – Hawthorn East
The Coles head office complex in Hawthorn East has long been held up as one of the finest examples of planter box and on-slab planting in Melbourne. Time and time again, Landscape Architects have given evidence in VCAT, stating that planter box and on-slab planting is possible. The Myer building is often used as the best example in Melbourne.
Tree Logic has been involved on this site for several years as the managers come to terms with the decline faced by the site vegetation. Several investigations have linked the cause of this decline to a range of issues but predominately limited soil root zone volumes and poor soil qualities are the issue.
The above images show the significant decline in areas with limited soil volumes (planter boxes) and poor quality soils and limited volumes (on-slab plantings).
The original plantings around the building included a range of planter box and on-slab sites with a range of tree species and other vegetation. Aerial photographs from 2004 and 2006 through to 2010 show a significant decline in vegetation areas and the loss of all the trees sited in planter boxes located along Toorak Road.
Note the areas outlined in red. Now there has been significant removal of trees and other vegetation with no trees in the Toorak Road planter boxes and trees and vegetation completely removed form several internal courtyard areas.
These images it can easily be seen that while the trees and other vegetation planted around the building initially established, the trees only just established and then started to decline. Within a period of approximately six years the trees and other vegetation had declined so badly that it has been all removed and the design of planters and courtyard areas changed to reflect the difficulties of vegetation management.
The above photographs show the very poor condition of the declining trees in the Toorak Roadplanter boxes and alongside the main building prior to them all being removed.
This site should show a clear message to planting designers that limited root zone volumes for large trees just does not work and that while the trees may grow for several years after planting, ultimately the limited root zone volumes will see trees decline and require removal.