Alexandrina Township's Tree Canopy Study
Planting trees is an investment for our future. We all enjoy mature trees that were planted a long time ago, including the shade that trees provide during hot days: We park our cars under trees, or enjoy our picnics in the shade of a tree.
Trees provide us with many benefits, as shown in Figure 1 below.
Figure 1: Benefits of community trees (Source: Tree Cities of the World)
South Australia is getting warmer from the impacts of climate change and the urban heat island effect, a concept that directly impacts the communities within the Alexandrina Council. Trees can help mitigate these effects as demonstrated in Adelaide’s Urban Heat Mapping, where mature trees can reduce local temperatures by as much as 20 degrees Celsius.
Besides the obvious benefits of providing us with oxygen and shade, township greening was one of the priority items discussed during Alexandrina’s A2040 Village Conversations. Similarly, tree canopy coverage is a key indicator for not only the health of our environment but also the community.
Hence, Council needed understand the existing canopy cover across our townships, so we know where to plant best.
Our study showed that the overall canopy cover averaged 17.6% across our 11 townships; ranging from 11.7% (Milang) to 49.3% (Ashbourne). This is similar to other studies found in neighbouring councils, such as Playford with an urban tree canopy of 15%.
To find out more about the study or see the results per township, see below.
Alexandrina's Tree Canopy Report
In March 2023, Council adopted the Tree Canopy Benchmark Study and Thermal Imaging Report (the “Tree Canopy Report”) that investigated the following three key aspects:
- tree canopy baseline for 11 townships;
- thermal imaging to demonstrate the urban ‘heat island’ effect across these townships (‘heat maps’); and
- canopy cover by landholder (Council land, private land; and Crown land).
Our study showed that Alexandrina’s overall canopy cover (tree cover) averaged 17.6% across our 11 townships; ranging from 11.7% (Milang) to 49.3% (Ashbourne). This is similar to other studies found in neighbouring councils, such as Playford with an urban tree canopy of 15%; while the average for Adelaide metropolitan councils is 23.4%.
Much of Alexandrina’s canopy cover is located on private land with 78%. In comparison, Council managed land has 21% canopy cover, and 1% of trees are found on Crown Land. From this information it can be calculated that only 1% loss of canopy of privately owned land would require a 20% increase in canopy cover on Council managed land.
This is why we all need to work together if we want to keep and increase our tree canopy cover.
You can download the full Tree Canopy Report here.
To find out the results for each township, click on the links for each township below:
The map below shows the townships that were assessed in the study.
Figure 2: Map showing the 11 townships assessed in the study (Source: Google Maps, accessed March 2023)