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World Forum on Urban Forests raises global Call to Action

Urban Forests


Held in December 2018 in Mantova, Italy, the inaugural World Forum on Urban Forests has moved forward by launching an eight-point Call to Action. The Call to Action aims to maximise the benefits of global urban greenery, create healthier and happier cities, and mitigate the impacts of climate change on the world’s cities.

The Call for Action promotes a vision where urban and peri-urban forests, trees and other green infrastructure will be acknowledged as critical infrastructure and used as a tool for achieving sustainable development goals.

The Forum put forward the following set of eight forest solutions to make cities greener, cooler, healthier and safer.

  1. Expanding canopy cover in cities and “using the right tree in the right place”;
  2. Promoting community gardens, urban agriculture and urban flood forests;
  3. Increasing the number of green buildings and vertical forests and encouraging installation of green roofs
  4. Converting neglected areas, courtyards and brownfields into green spaces;
  5. Developing political agendas that promote green spaces and urban forests;
  6. Using existing technical guidelines to plan, design and manage urban forests and trees;
  7. Creating and promoting green jobs and economic opportunities; and
  8. Monitoring the ‘heat island effect’ in cities to support strategic planning or urban forests.

The World Forum on Urban Forests was attended by government representatives, urban planners, arborists, landscape designers, architects, academics and other forestry experts. It discussed global greening strategies, long-term collaboration opportunities, and identified sustainable solutions for a greener future.

Over 600 participants from around the world, including over 150 speakers, shared positive examples of urban forest design, planning and management, illustrating the role of forests and green spaces in creating more resilient and sustainable cities.

For more information on the World Forum for Urban Forests, visit

The positive impact of trees – from economics to health

Positive impact of trees

Considering Australia’s excess carbon emissions, trees are useful to have around. Through the miracle of photosynthesis, trees breathe in carbon dioxide and breathe out vital oxygen. However, trees do far more for Australia than help with our greenhouse problem.

For a start, trees make us happy. Studies from Australian universities analysed 2.2 million tweets on Twitter and found that tweets made from parks were more positive in nature than tweets from built-up areas. So why are people in parks so happy?

In a world that’s becoming increasingly urbanised, parks provide a welcome respite from the stress of living in cities. With nine out of 10 Australians living in urban areas – and two thirds of us living in capital cities – more people are flocking to parks to exercise, meet friends and attend events. We’re also getting back to nature to combat the health risks – both physical and mental – of high-density urban living.

Decades of research shows that experiences of nature are associated with a wide range of positive health outcomes, including improved physical health (such as reduced blood pressure and allergies), improved mental health (such as reduced stress), greater social wellbeing and uptake of positive health behaviours. Whether it’s walking the dog, strolling in the park or playing games outdoors, being connected with nature provides proven relief from stress and anxiety.

Then, of course, there are the environmental and economic benefits that urban trees undoubtedly bring. According to environmental planners at Griffith University, Australian cities are getting hotter, noisier and more crowded – and climate change is causing more heatwaves. Rather than increasing air-conditioning, which in turn increases carbon emissions, the better solution is green infrastructure – street trees, green roofs and walls, and vegetated surfaces.

Compared to hard surfaces like concrete, asphalt and stone, which increase urban temperature, green roofs and walls can naturally cool buildings, significantly lowering the need for air conditioning. Plus, according Griffith’s environmental planners, shading from strategically placed street trees can lower surrounding temperatures by up to 6 degrees – or up to 20 degrees over roads.

Considering the wide-reaching positive outcomes to environment, happiness and health, if there’s one thing Australia’s economy needs more of, it’s trees.

Aussie street trees keep cities cool and power bills down

Aussie Street trees

Australian summers can be devastatingly hot. As the mercury continues to rise this season, an urban greening movement is campaigning for more trees to cool the country.

Dr. Tony Matthews, Griffith University urban and environmental planner and 202020 Vision advocate knows that street trees play a vital role in reducing heat. Without trees, heat is absorbed by hard surfaces like concrete and radiated back into the air. This is commonly known as the “urban heat island effect”. That’s why he’s working with 202020 Vision – a group that includes some of Australia’s leading green space experts – to make urban spaces at least 20% greener by 2020.

However, it’s not just the cooling benefits that make street trees so vital. As Dr. Matthews explained, trees benefit resident’s health and can even boost their bank balances by reducing power bills.

“People in areas with less greenery and more housing density; their bills are going to go up,” Dr Matthews said. “So, the people who can least afford higher electricity bills ending up paying for them.”

Plus, communities with more shade from trees were more walkable, Dr Matthews said. Green spaces encouraged people to get outdoors and, in turn, contributed to social cohesion.

As for how to reach the goal of increasing Australia’s greenery by 20% by 2020, Dr Matthews said local councils had a major role to play in ensuring that trees were integral to new developments.

“Councils, through their planning [schemes], need to start insisting on tree cover and tree provision,” he said. “Once a housing estate is finished it’s up to the council to maintain and pay for trees and green space … councils are reluctant to do that [at the moment] because of the cost.”

While the cost of tree planting and maintenance may be high, the huge savings in health and wellbeing far outweigh the price, according to occupational heat stress consultant, Matt Brearley.

“There’s a lot of people exposed to the urban environment. It’s extremely important to mitigate that outdoor heat for those outdoor workers,” said Mr Brearley. “We need cooler environments in our urban settings, so workers don’t suffer heat stress.”

“A cooler environment allows a bigger window for the public to do what they want to do, whether it’s working or walking”, he added.

Lyndal Plant, an urban forester, said Australians were also prepared to pay more (3.73% to be precise) for houses on leafy streets, and even more in cities where tree cover is scarce.

“In my study, for every dollar invested in the planting and maintenance of street trees there would be a return of at least two dollars”, she said.

Milan’s plan to plant three million new trees by 2030

3 Mil trees

Milan in Italy is often plagued by muggy, almost tropical weather. However, an ambitious plan to plant three million new trees by 2030 could offer relief from the stifling weather. As well as helping to lower temperatures, the trees will play a major role in mitigating pollution and combating global warming.

Officials estimate that boosting the number of trees by 30% in the broader metropolitan area will absorb an additional five million tons of carbon dioxide each year (four-fifths of the total produced by Milan), plus reduce harmful PM10 small particulates by 3,000 tons over a decade. They also predict the new trees will reduce city temperatures by a significant 2C.

Renowned architect Stefano Boeri said the current green canopy of the Lombard region’s capital accounts for only 7% of the urban area – well below other European cities, like Frankfurt at 21.5% or Amsterdam at nearly 21%.

The plan is to increase this green canopy to between 17% and 20% by 2030 and, ultimately, lower

temperatures in a city where the evening mercury can be 6C (10.8F) higher than in the surrounding area.

According to city statistics, Milan endures around 35 tropical nights a year. Because of its location close to the Alps, there is very little wind to clear pollutants that become blocked in by temperature inversions, where a layer of cool air is covered by a layer of warmer air.

Plus, as Damiano Di Simine, the scientific coordinator in Lombardy for the environmental group Legambiente, describes, this also contributes to urban heating.

“It means the discomfort from thermic inversions is terrible, because the climate is very stationary. Planting trees will help this”, Mr Di Simine said.

Some ad-hoc projects have already contributed to environmental improvements, such as Mr Boeri’s Vertical Forest residential towers, completed in 2014. However, if Milan’s plan is any indication, the Vertical Forest is just the beginning.

Canberra’s City Renewal Precinct set for a green makeover

Canberra Green makeover

Canberra’s City Renewal Authority has unveiled new plans for a greener and more people-friendly inner city. As part of its new sustainability strategy, released late in 2018, the authority has set some lofty targets to include more trees and green spaces, more energy and water efficient buildings, and a more diverse mix of housing in the City Renewal Precinct by 2025. It also aims to get people more active by making it easier to walk and cycle there.

The targets include:

  • Improving housing options for families by increasing the number of three-bedroom apartments.
  • Increasing active travel by targeting a “Walk Score” of 90+ by providing accessible community and commercial services within a 10-minute walk from anywhere in the precinct.
  • Improving energy efficiency from new buildings, with non-residential buildings to have energy performance at least 25% above code.
  • Reducing potable water demand in new developments by half, plus replacing 30% of public water with re-used storm water.
  • Minimising car ownership within the precinct by increasing electric vehicle charging infrastructure.
  • Achieving 30% tree canopy cover within the precinct, with increased greening of urban and open spaces between buildings.

Malcolm Snow, Chief Executive Officer, said the 2025 targets were designed to make Canberra more environmentally, socially and economically sustainable – and to meet the high expectations of the community.

“We share with the community a desire to create welcoming, inclusive places that value social connectedness, community health and wellbeing. Places that allow people to connect with nature, and with each other, in their everyday lives,” he said.

“Social and environmental sustainability are vital elements of our program as we implement the design-led and people-focused renewal of our city precinct.”

The strategy will be led by the authority and rolled out with support from other government agencies, private companies and community groups.

“We will implement the targets through our own capital works and land release programs and also work with developers and community groups to promote best-practice sustainability initiatives throughout the precinct”, Mr Snow said.

“We will also collaborate with the private sector wherever possible to encourage the uptake and application of sustainable development practices in new development projects.

“Achieving sustainable development will require collective urban leadership – everyone has a role to play to help create the city we all want to live in and our children to live in.”

To view the City Renewal Authority’s sustainability strategy visit:

Six international cities with outstanding green infrastructure

Top Green cities

Six international cities with outstanding green infrastructure

Green infrastructure and urban sustainability are becoming increasingly high priorities for cities all around the world, however some are already streets ahead. Here are six of the top cities who are leading the pack.


  1. Singapore

Now known as one of Asia’s greenest cities, Singapore’s water supplies were once so scarce that they had to import water from Malaysia. However, Singapore has since turned things around, making two-thirds of the city’s hard surfaces rainwater catchments, which deposit water to 18 reservoirs.

Other sustainability systems include advanced water purification and recycling processes, a driverless metro and environmentally-friendly meeting venues.


  1. Stockholm

Stockholm in Sweden became the first European Green Capital in 2010, thanks to an administrative system that makes sustainability a priority. In Stockholm, eco-taxis get preferred placement at the front of taxi ranks, while more than 700 kilometers of bike lanes and a community bicycle rental program encourage people to cycle rather than drive.

Stockholm even has an official ‘eco-district’, located in Hammarby Sjöstad. Its goal is to halve the carbon footprint of a typical city, by providing residents with gas and electricity from renewable sources, as well as houses made from raw materials.


  1. Virginia Beach, VA

Virginia Beach is ranked second on the Environmental Protection Agency’s list of mid-sized cities with the most buildings that also received the ENERGY STAR rating for energy efficiency.

The city has a strong focus on school-related sustainability, with the Virginia Beach public school system being the only K-12 division to receive a Governor’s Award for Environmental Excellence, which recognises continual efforts made toward conservation.


  1. Portland, OR

When Portland residents voted in the 2018 midterm elections, they favoured a ballot initiative that imposed a one percent tax for large corporations. The revenue generated by this initiative will go toward supporting change minimisation strategies in the city.

Earlier in 2018, Portland also made single-family home owners responsible for disclosing their home’s energy efficiency rating (measured by a professional assessment) before putting their home on the market. This allows potential buyers to make more informed purchasing decisions, while also encouraging sellers to make their homes more sustainable.


  1. Boston, MA

Boston’s goal is to be carbon-neutral by 2050, and the city is also working towards a zero-waste goal. The climate change plan involves planting trees to help absorb floodwaters that could result from worsening storms, plus looking at ways to reduce greenhouse gas emissions by giving residents sustainable transportation options.

In Boston, there are nearly 200 bicycle rental stations. The city is also considering how to accommodate more electric vehicles by installing more convenient charging points.


  1. Vancouver, British Columbia

Vancouver is the third most sustainable North American city, according to data published in 2017. Notable green initiatives include the Tap Map app, which helps people find places to refill their reusable water bottles. In 2015, Vancouver also banned organic materials from landfills, encouraging people to recycle their food scraps.

In terms of urban buildings, Vancouver has a particularly eco-friendly landscape and scores a higher-than-average rating for walkability. That means fewer vehicles, less pollution and a smaller carbon footprint.


Darwin to increase tree canopy in response to Cyclone Marcus

Darwin to increase tree canopy in response to Cyclone Marcus

Darwin Council has set a lofty long-term goal to cover half of the CBD in natural tree canopy by 2030. The plan comes in response to a report into the aftermath of Cyclone Marcus, which claimed more than 10,000 trees in early 2018.

The report, prepared by the Tree Re-establishment Committee (TRAC), focuses on developing an urban forest management plan, and is supported by Darwin Lord Mayor Kon Vatskalis.

“We want to plant as many trees as possible, create a canopy over the streets and cool down the city,” he said.

“(TRAC) had the look at the report from the cyclone … they also had a look at reports in other places where trees caused destruction and looked at which ones fell down and which ones stayed up,” he said, adding that TRAC also returned a list of 194 trees that were suitable to the local environment.

While the Mayor advised that major plans would start rolling out in early 2019, members of the local community have already embarked on replanting projects to breathe new life back into Darwin. In November 2018, one key location in each of Darwin’s council wards was targeted for a ‘replanting day’, with several replanting days scheduled since.

“The community planting days are a great way for the community to come together and help council get areas that were severely affected by Cyclone Marcus started on their recovery and bring areas back to life with new trees” said Lord Mayor Vatskalis.

He also said that, while efforts would continue well into the future, the replanting projects were a wonderful start and would allow Darwin residents to get a better understanding and appreciation of the extent of Cyclone Marcus’ damage.

“Replanting will be ongoing for many years to establish a diverse and resilient urban forest. I encourage local residents of all ages to come along and help rejuvenate these spaces.”


Swinburne trials world-first urban forest management project

The sensors in the instrumented trees at CERES provide constant, real-time watering data.

Swinburne trials world-first urban forest management project

A new pilot program led by Swinburne is using water-sensor technology to better manage urban forests in Melbourne.

Dr Scott Rayburg, Swinburne Water Resources Engineering senior lecturer, and his team have joined forces with ICT International and RMIT University to install $31,000 worth of tree water sensors at CERES Community Environment Park – a not-for-profit sustainability centre located in the inner-city suburb of East Brunswick.

The sensors are designed to create stronger, healthier urban forests. They also enable park managers and members of the community to track the progress of trees via online platforms that provide real-time data on water use and water stress.

During the pilot, data will be collected via sensors attached to the trees. It will be used to determine the most suitable species for current and future climates. It will also allow forest managers to determine how much water to apply to their trees, and when.

Dr. Rayburg says, “The project is transformational. Instead of trees dying at 80 years of age because they are spending their whole lives in water stress, they’ll live to be two or three or maybe even four hundred years old. That matters because when we lose a tree in an urban landscape we lose habitat, we lose cooling, we lose a part of ourselves, and people have a really visceral connection to trees.”

He also notes that this project is the first of its kind in the world, saying “These sensors have previously been used in agriculture and plant biology, but never before in an urban forest management setting.”

The sensors are the first stage in this pioneering project, which plans to go one step further with an app that allows the trees to ‘talk’.

“The City of Melbourne has a platform called Urban Forest Visual that allows people to send an email to a tree and then somebody from the City of Melbourne responds to the email,” Dr Rayburg says. “This has been really popular, which demonstrates the desire people have to interact with nature, even in cities.”

“We want to take this to the next level; instead of a person responding, we want the tree to respond.”

The proposed app will allow members of the community to contact a tree and ask how it’s going. Using the real time watering data, the tree will send back an instant response which might confirm its feeling healthy, or even ask for some water.

The hope is that the app will get more people engaged with Melbourne’s urban forest and tree health, taking some pressure off local councils.

Main image: The sensors in the instrumented trees (as pictured) at CERES provide constant, real-time watering data.


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