by Eliza Booth, Editor, Council magazine
As our cities continue to grow and our urban environments become more densely populated, city planners are turning to urban greening initiatives to offset some of the negatives that urban growth can have on the environment and the wider community. But what exactly is urban greening, why is it vital to our growing cities and what is the current state of urban forestry in Australia? Council Editor Eliza Booth takes a closer look.
Australia’s capital cities and regional centres are growing. In 2020, Melbourne experienced the largest population growth of all cities in the country with over 80,000 new residents calling Melbourne home.
Further north, Brisbane experienced the highest growth rate of any Australian city at 1.9 per cent¹, showing that people love living in our cities and enjoy the exciting opportunities that come with it.
However, with more people moving to our cities and regional centres, there also needs to be the infrastructure to facilitate them. This can lead to a decrease in green spaces as new buildings and homes are constructed.
But not placing a big enough importance on green spaces can seriously negatively impact our cities and residents. Green spaces in urban environments can help keep our cities cool, improve air quality, limit the effects of climate change, and positively impact residents both mentally and physically.
And the best part is that urban greening doesn’t just need to be confined to a large park with trees, it can incorporate rooftop gardens, community gardens, street trees, living walls and apartment planter boxes – there is no limit to the creativity urban planners can use when incorporating greenery into city designs.
What is urban greening?
Urban greening refers to the process of designing, installing and ensuring urbanised environments have adequate green spaces.
Urban greening combines landscaping, expert knowledge and innovative design to create beautiful green spaces, with street trees and parks being some of the most recognisable examples of greening in our communities.
As new buildings and infrastructure are constructed, city planners must consider the impacts these assets will have on the community and environment.
Urban greening helps to offset some of the negative impacts of urbanisation and city planners are able to plan greening projects accordingly to enhance the look of the surrounding environment, improve air quality, provide community spaces for residents and even increase the feelings of calm and tranquility for residents.
The best options for greening will depend on many factors, like the size of the space available, whether there are already existing trees in the area or if some need to be planted, the possibility of rooftop green spaces, or even if there is the ability to install a vertical garden on the side of a building.
There are an unlimited number of ways urban planners can design and install green spaces in our cities, however, there are some major considerations hat planners need to think about when planning greening projects.
The type of trees or plants that are going to be used is a major consideration. Planners need to think about the changing climate conditions of their cities and what types of greenery will thrive best in these environments – there’s no point placing a tree that needs lots of water into an environment that experiences minimal rainfall.
Similarly, greenery needs to be chosen for the way they interact with local wildlife and native flora and fauna. Enlisting a horticultural expert will help planners to choose appropriate greenery for their individual cities to create a holistic and harmonious environment.
City planners also need to consider how much upkeep certain projects may need in the long term. Will newly planted trees need an irrigation system installed to help them grow?
Is there sufficient drainage in the area to accommodate an increase in greenery or will more drainage need to be created? Is there sufficient sunlight and appropriate soil to facilitate greenery?
Additionally, the way in which the public use and interact with urban spaces needs to be considered when planning greening projects.
Perhaps the community needs a new dog park or better trails for walking or exercising. Maybe there needs to be better canopy cover in existing parks to keep the community cool and protected from the harsh Australian sun.
All of these and many more considerations need to be discussed in the planning stages to ensure harmony in the ecosystem and that infrastructure is not damaged or compromised by greening.
By planning properly, cities and regions will be able to create green spaces that are self-sufficient, sustainable, practical and look beautiful.
Why are urban forests and urban greening important?
Urban forests and greening have a range of amazing benefits for cities and communities to enjoy. Urban greening also provides a beautiful background for people to live and move around in, which has proven benefits for humans mentally and physically.
One of the biggest impacts that urban greening has, and one that is the most immediately obvious, is the beautification of an urban area. This doesn’t just help a suburb or city look more aesthetically beautiful, but it can also have a really positive effect on the mental health of residents and visitors.
Green spaces are scientifically proven to increase the feelings of calmness and tranquility in humans, while also improving neighbourhood satisfaction, reducing aggression and transport stress, and it can even promote better healing².
Another major benefit of urban greening is that it helps keep cities cool. As climate change continues to affect our weather, and our summers become hotter, increased tree coverage across our cities helps to insulate our streets and protect us from the harsh sun.
Data collected from several studies suggests that urban areas with greening can be 1 degree cooler than other areas without, and that both canopy cover and ground vegetation play an important role in cooling³.
Prioritising urban greening as our cities and populations grow will ensure everyone gets to enjoy green spaces where they live, long into the future.
Snapshot of greening across Australia
Now that we have a better idea of what urban greening is and how it benefits our communities, let’s take a look at what some of Australia’s major cities are doing in the green space and what they hope to achieve through their initiatives.
The City of Perth’s Urban Forest Plan was released in 2016 and details the city’s journey over the next 20 years to grow and care for the city’s green spaces.
The plan outlines a major focus on protecting the current green landscape through strategic management, with a key focus on improving the amount and quality of canopy cover across the city, which is the amount of urban land that is covered by trees when viewed from above.
Having a high percentage of canopy cover has numerous benefits for cities including helping to reduce heat at ground level as well as reduce the impacts of climate change.
Perth’s forest plan says that it sees its urban forest as an important piece of the city’s infrastructure and as such, it will prioritise its protection and promote sustainable growth, improve vegetation health, and build its resilience to offset urbanisation and climate
The Plan outlines nine main objectives which will improve the quality of the City’s urban forest: protect existing trees; replace trees that are aging or dying; promote sustainable water management; increase the quantity and quality of canopy cover; prioritise tree planting to help with city cooling; promote balance and resilience in species composition; maintain tree health; implement a ‘whole-of-forest’ management approach; and encourage community engagement with green spaces and urban forests.
In 2014, City of Melbourne released its first ever Urban Forest Strategy which aimed to protect Melbourne’s urban forest – which encompasses approximately 70,000 council-owned trees – from climate change and urban growth.
The City implemented this plan following more than a decade of damaging drought and heat waves. Combined with aging tree stock, the city was concerned it could lose up to 44 per cent of it’s trees over the next 20 years if nothing was done to improve urban greenery.
The Urban Forest Strategy’s main purpose was to protect against future vulnerability through strategic framework, collaboration, and a holistic, ‘whole-of-forest’ approach, creating a lush and sustainable urban forest for all stakeholders.
The Strategy included six key strategies and targets which were: increase canopy cover; increase urban forest diversity; improve vegetation health; improve soil moisture and water quality; improve urban ecology; and inform and consult the community.
The City of Melbourne says in their strategy that their focus is to build the city in the forest instead of trying to build a forest in the urban environment, showing that creating a green city is just as important as building essential infrastructure
Brisbane’s subtropical climate makes its urban forest unique and diverse, combining a mixture of native and exotic species. Brisbane’s tree canopy covers 44 per cent of the local government area with 57 per cent of this canopy cover situated on public land.
The City of Brisbane set several goals to achieve for the future to enhance, sustain and protect its urban forest. These goals include increasing canopy cover to 50 per cent over residential footpaths and bikeways by 2031, increasing the amount of green shade at bus stops across Brisbane, and transforming major roads leading into the city to subtropical boulevards.
Brisbane City Council also continues to prioritise maintenance of trees and vegetation located on council land, including caring for newly planted trees, inspecting and trimming trees and vegetation as needed, removing or replacing trees that may be hazardous or disrupting biodiversity, and ensuring the urban forest is prepared for extreme weather events.
Thanks to Brisbane’s urban forest and conservation of its vegetation, the city’s trees help to store an estimated 1.9 million tonnes of carbon, remove approximately 1.45 million tonnes of carbon dioxide per year (or 10 per cent of the city’s emissions), and help to keep parts of the city up to seven degrees cooler than areas without trees⁴.
In 2016, Sydney released its Environmental Action 2016 – 2021 Strategy with its Urban Forest Strategy as a supporting document outlining its goals to increase tree canopy, and maximise economic, social and environmental benefits the city’s urban forest can provide.
Through the strategy, Sydney aims to improve the quality of its urban forest through several key initiatives. The first is to prioritise the maintenance and protection of its current tree population to ensure it is healthy and sustainable.
The next initiative is to increase the total canopy cover of the city from 15.5 per cent to 23.25 per cent by 2030, and onto 27.1 per cent by 2050.
As Sydney is a more densely populated area, increasing the canopy coverage to these levels is achievable and will have major benefits.
The City of Sydney also aims to improve the age and spread of its trees, as well as increase the species diversity for a more harmonious and sustainable environment.
Finally, the City aims to improve engagement with the community to help educate them on the maintenance needs of the urban forest
while supporting the community’s participation in greening projects.
As the Environmental Action Strategy ends in 2021, it will be the next iteration of this strategy that will determine if there are any further changes or developments to the Urban Forest Strategy too.
Greening for the future
This is just a small snapshot of the important work being undertaken in urban greening across Australia. While some cities have dedicated strategies for their urban forests, others are focusing on their green spaces in their own individual ways, whether that’s through a focus on planting more trees, improving parks, installing new technology to help monitor their green spaces, or investing in sustainable initiatives to improve their carbon emissions.
Regardless of individual approaches, it’s clear that urban greening is a top priority for cities and regions across Australia. With so many cities realising the invaluable benefits of urban greening, we will be able to see, feel and enjoy our growing green spaces for generations to come.