Trees increase property values, act as natural air purifiers, enhance the health and wellbeing of communities, and can reduce land surface temperatures in urban environments. A new research study by TCL, a national design practice made up of urban designers, landscape architects and master planners, provides compelling evidence to substantiate why trees must be prioritised at the outset of any design process. The study, A Case for Trees, was recently collated as a guide for governments, councils, developers and homeowners.
Speaking in the context of the ongoing development of Western Sydney, local landscape architect Terrence Stapleton who heads the Sydney studio of TCL underlines the importance of trees in the planning process.
Given that it may take 20 years for trees to reach maturity, their size and siting need to be planned well in advance, he says. “Adequate space and soil for large, leafy tree canopies and deep root systems must be considered before new residential developments, services and infrastructure are complete in Western Sydney.”
Western Sydney, considered NSW’s fastest-growing region, is set to take off with a new international airport and proposed precincts of more than 5,000 homes. With extensive farmland and greenfield sites, the area lacks the wide tree canopies, commonly seen in leafy suburbs such as Mossman, Balmain, Willoughby and Annandale.
A Case For Trees cites AECOM‘s Green Infrastructure Report – a study of three Sydney suburbs that suggests a 10% increase in a street’s tree canopy could increase property values by an average of $50,000, and reduce energy bills by up to $400 every year.
TCL UNSW Village Green; Photo Credit: Brett Boardman
Trees are also natural air purifiers, says Stapleton, producing significant amounts of oxygen that help mitigate carbon emissions and other pollutants. They can also counter rising summer temperatures: Research by the City of Sydney indicates that for every 10% increase in the urban forest canopy coverage, land surface temperatures can decrease by 1.13°C. In fact, one tree cools the same as 10 air-conditioners running simultaneously per year.
Trees should also be selected to suit climatic conditions, he says. “The climate has changed so much that the species we traditionally favoured for Sydney are now no longer able to survive these hotter conditions. So it makes sense to source species robust enough to withstand more tropical conditions.”
In response to vandalism of public trees, Stapleton says, “Firstly, well-designed public spaces should honour and protect existing, established trees.
“Secondly, the evidence is clear – trees are an incredible natural resource that benefits our mental and physical health. Destruction of that resource is not only reckless but detrimental.”
A Case for Trees comprehensively outlines the health benefits of trees, citing research that reveals communities with street trees have reported better overall health outcomes in comparison to communities with none.
The potential of tree canopies to reduce exposure to UV rays, mitigate heat-island effect and promote wellbeing by walking ‘in nature’ are all well documented in the research.
