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How Europe’s Greenest Capital Is Saving City Trees

“Covered either by bristling forests or by foul swamps” is how Tacitus described the wildlands of Germania in 98 AD. While those ancient trees, from which Teutonic tribes emerged to maraud the Romans, have long since vanished, modern Germany’s capital is still home to a vast and vital urban forest.

Berlin is one of the greenest cities in Europe: About a third is taken up by parks and green spaces, and the streets are lined by more than 430,000 street trees. Lindens (also known as lime trees or basswoods) are the most common, their heart-shaped leaves visible all over the city. They even lend their name to the grand central boulevard, Unter den Linden, once Berlin’s answer to the Champs Elysée or 5th Avenue.

Street lindens belong to the cityscape as much as the palms of LA or the sakura of Tokyo, though few of Berlin’s thousands of streets trees are older than 70. During the 1940s, 60%of street trees were wiped out by the onslaught of the Second World War. Trees that survived the Allied bombing were cut down for firewood in the freezing winters that followed.

(Photo by Marco Derksen / CC BY-NC 2.0)

Post-war, reforesting the ruins became an act of restoration and resilience. The first linden was replanted in the Tiergarten in 1949 by Mayor Ernst Reuter, during the Soviet blockade of West Berlin. The replanting effort was judged to be so important for morale that, along with essential food and fuel supplies, up to 200,000 young saplings were flown into the divided city by the U.S. Air Force.

Now, Berlin’s recovered tree population is once again at risk — this time from a chronic drought — and a new app has been launched to save them.

Gieß den Kiez (Water the Neighborhood) is an interactive platform that invites users to keep an eye on local trees and in times of need, bring them a bucket of water or splash from a hose. The map displays over 600,000 individual trees (both street trees and park trees), together with up-to-date information on species, age, water needs, and recent rainfall.

The prototype was developed at CityLAB Berlin, a research and development hub funded by the Berlin Senate and Technologiestiftung Berlin. Julia Zimmerman is part of the team. “We want to show people what kinds of digital solutions there are for real-life problems,” she explains. For most users, the map gives a completely new perspective of life on their street. “That was the first thing I did with the website,” Julia says. “Check which trees are growing outside my front door.”

But it’s not just a novelty. For the first time in generations, tree numbers in Berlin are falling. The principal cause is extreme weather. First came Cyclone Xavier in 2017, which uprooted and damaged thousands of trees across the city. Then came chronic droughts: Both 2018 and 2019 recorded high temperatures and minimal rainfall in spring and summer, and 2020 is shaping up to follow the same pattern.

“The situation is very urgent,” explains Christian Hönig from the environmental group BUND-Berlin. “In the last very dry years since 2018, the annual number of street trees felled has increased by about 20 %.” Street trees bring a host of benefits to the city. They regulate temperature, filter airborne pollutants, and provide a home to local wildlife. “They also shape the space we live in,” says Christian, “just like architecture.”

Urban tree care does not come cheap, however, and Berlin’s finances are famously dire. According to the Berlin Senate, it costs €2,000 (about $2,250 USD) to plant and maintain a tree in the first two years, during which time the young plantings can need as much as 50 litres (13 gallons) of water per day if temperatures are high.

Faced with dramatic tree losses, the city has already made €22 million (about $26 million USD) of extra funding available to district councils for 2020, and spending per street tree has been increased from €48 to €82 ($56 to $96). An annual campaign is also underway to raise donations from the public.

But as temperatures rise and skies above Berlin remain blue, street trees young and old need all the help they can get. This is where Gieß den Kiez, with its model of neighbourhoods watered by the neighbours, could bring about a radical change in how city trees are cared for.

Every tree in Berlin is mapped so users can see how much water a tree has received and how much it still needs. (Screenshot from Geiß den Kiez)

The prototype went live in May and in the first six weeks, registered 1,000 unique users and over 7,000 individual tree waterings. “The first weeks were totally crazy,” Julia laughs. “Through coronavirus, I think a lot of people found more time for themselves and also for their environment, for nature.”

User numbers are still rising daily and community groups are using the platform to coordinate their watering activities with local authorities. She is also pleased to see that elderly users are getting in touch with questions about using the platform. “The issue is encouraging older people to get to grips with new technology.”

“I find it really beautiful to see the issue is so important to the people of Berlin,” she adds. “I’m optimistic when I see how big the community is, how much the different district councils are reaching out to us. They all seem to have woken up.”

Open tree data

Open platforms like the Gieß den Kiez, which make public data accessible, can be a powerful way to get citizens engaged in city issues.

“It can help people to have a better appreciation of how it is the government does what it does, so there’s less of a wall between them and government, as this mysterious thing,” says Steve Benett. He is the founder of Open Trees, the world’s biggest database of open tree data. Using datasets from public sources, he has mapped street and park trees from cities around the world onto a single global map.

“It’s not that obvious to the average citizen just how many frickin trees there are,” he says. Visualisations like his can help people understand the challenge of caring for hundreds of thousands of trees in a major urban area. “You get this squeeze, where the government has to turn back to the citizens and say, well maybe we can’t water all the trees, maybe you’re going to have to come and help out.”

Sharing stewardship online

Cities in the U.S. have been experimenting with similar platforms, to win more volunteers in the fight to protect and care for urban forests.

The New York City Tree Map is run by the NYC Parks Department and shows data on 692,892 trees across the five boroughs, including a log of volunteer care activity, from watering to mulching, and a running tally of the annual value of urban trees to the city (currently $104,991,168.49, a reflection of trees’ roles as shade, carbon dioxide and pollution removers, and stormwater retainers).

“The map is intended to be the one-stop shop for New Yorkers to learn about and care for their street trees,” says Dan Kastanis from NYC Parks. Built from data gathered by an army of volunteers in the 2015 tree census, the map is designed to give a live connection to the status of each individual tree, as well as resources on tree care and community workshops. Though New York’s map is the most sophisticated, other cities like Washington, D.C., Seattle, San Francisco and Los Angeles have all published their tree data on similar platforms.

These projects all share the conviction that finding engaging ways to visualise and interact with data can inspire locals to get involved and become active volunteers. Tree stewardship is a model in which citizens and local government share the work of tree care, not just in seasonal crises like a drought but on a basis of long-term cooperation.

“We believe stewardship of our urban forests requires a team-based approach,” says Rachel Holmes from The Nature Conservancy. In collaboration with the U.S. Forest Service and the Center for Invasive Species and Ecosystem Health at the University of Georgia, she works on Healthy Trees, Healthy Cities, another tree care and mapping platform. “By first educating people about trees and what they need from us, and then providing an accessible mechanism through which people can meet these needs, we are hoping to inspire a lifelong connection to nature and commitment to its care.”

Sharing responsibility

Yet the burden of ownership which online stewardship seeks to foster is not always welcome. Some communities raise concerns about the maintenance costs of new trees. In San Francisco, for instance, homeowners, and not the city, bore legal responsibility for any damage caused by trees growing in the sidewalk adjoining their property — including eye-watering bills for root damage to sewers — until the law was changed in 2016.

Street trees also bear out the legacy of social and economic inequality. A 2016 study of the City of Los Angeles found the benefits offered by street trees was skewed, with nearly a fifth of the urban canopy growing in an area where only 1% of the population lives. At the same time, planting trees can seem tokenistic in the face of long-standing neglect. In Detroit, there was pushback against tree planting initiatives by communities who felt abandoned by city authorities in so many other ways that they felt no stake in the planting of trees. If city forests are to be recognised and protected as green infrastructure, with benefits available for all, then addressing inequality must also be part of that conversation.

For Julia Zimmerman, community apps like Gieß den Kiez can help us recognise trees as a point of connection in the shared life of a city, part of its past as well as its future.

“Berlin is and will hopefully stay a green city,” she says. Along with one of her favourite streets, Puschkinallee, towering plane trees have stood since the late 1870s, improbable survivors of history. Their loss would be shared by all Berliners. “Especially in a city like Berlin, where the past is extremely moving — and the trees have lived through all of it with us.”

Source: Written by Edward Belleville based in Berlin

The critical role of ‘everyday nature’ for the future of cities

A growing population puts increasing pressure on biodiversity when residential areas encroach on natural systems. The Built environment report describes Australia’s urban footprint, and the implications for air quality, water quality and the natural environment.

As Australia’s population grows, additional urban land is required, or existing land is used more intensely. In Australia, population growth tends to be most concentrated in outer suburbs, in inner cities, in urban infill areas and along the coast. Our big cities continue to expand into natural areas on the city fringes, despite the well-recognised problems associated with higher infrastructure costs, lack of amenity, car dependency, poor job access, and diminished agriculture and open space (Newton 2012). In Melbourne, 50 per cent of the approximately 40,000 new dwellings built each year are in new greenfield sites (Buxton 2014). Targets for infill housing established in recent metropolitan strategic plans are not being achieved (Newton 2012).

The threatened Grassy Eucalypt Woodland of the Victorian Volcanic Plain is encroached on by Melbourne’s peri-urban zone, with woodland remnants cleared to allow increasing urban development. Additional growth centres are planned. In response, the Victorian Government is establishing conservation areas in and outside the growth corridors to protect threatened species and ecological communities of national and state significance, and to manage the impacts of urban development in urban growth corridors. Similarly, encroachment of urban development on the Cumberland Plain Woodland in the Sydney Basin has reduced the community to small fragments scattered across the western suburbs of Sydney, and it is now listed as critically endangered.

Urban development is a major driver of environmental change. Urban areas contain threats to, and opportunities for, biodiversity. The conversion or degradation of natural ecosystems in urban areas has the most obvious and immediate impacts on biodiversity. In addition, human settlements and development are often the entry point for introduced species, which are a major pressure on biodiversity. For example, non-native invasive garden plants, introduced to Australia by and for the urban population, make up an estimated 72 per cent of environmental weeds that affect biodiversity (Groves et al. 2005).

In contrast, the urban environment can prove an attractive habitat for a wide range of taxa because of abundant food and shelter. Urban areas may also provide more stable resources for some native species as a result of planting selection and supplemental watering. Some urban habitats, such as railway lines, abandoned industrial lands and urban wetlands, can be rich in native species and can play an important role in maintaining the biodiversity of a city.

Although the presence of wildlife in urban areas can enhance human quality of life (see Box BIO3), some urban animal populations can prove problematic because of their impacts on amenity or their role as vectors of disease. For example, roosting by flying foxes in urban and peri-urban areas can result in contact and conflict with humans. Human concerns include noise, odour and faeces from flying fox camps, particularly when they occur near residences. Transmission of disease, particularly Hendra virus and Australian bat lyssavirus, is also a key concern and has received much attention during the past few years. Although smaller camps are often tolerated, larger camps become a focus of community disquiet. The spectacled flying fox (P. conspicillatus) and grey-headed flying fox (Pteropus poliocephalus) are both listed as vulnerable under the EPBC Act. They have both shown marked changes in the distribution of their abundance during the past 15 years, in the form of increases in the number of urban camps and in the proportion of their populations found in urban contexts (Tait et al. 2014Westcott et al. 2015). It is unclear whether these changes represent responses to the development of appropriate conditions in urban areas, the deterioration of conditions elsewhere or the cessation of exclusion from urban areas. Regardless, the shift represents a major management dilemma, given the conflict it produces and the conservation status of the 2 species.

Cities are often located in areas with high biodiversity, and the process of urbanisation itself is likely to have led to many species that formerly occurred in these places now being threatened. In 2015, Ives et al. (2016) analysed the extent to which the distribution of 1643 species of national environmental significance under the EPBC Act overlapped with 99 Australian cities of more than 10,000 residents (Figure BIO5). They found that 25 per cent of listed plants and 46 per cent of listed animals had distributions that intersected with cities. The distributions of 8 threatened species (all plants) entirely overlapped with cities, whereas 51 (10 per cent) of the 503 threatened species found in cities had more than 30 per cent of their distribution in urban areas. The research showed that cities contain substantially more threatened species per unit area than non-urban areas.

Nature in cities delivers a remarkable range of benefits to human health and wellbeing. Individuals are more likely to live longer (Donovan et al. 2013), and have better general health and wellbeing (Dallimer et al. 2012) in a city with more trees.

Urban greening can substantially improve the resilience of cities to climate change, potentially cooling cities by up to 8 °C in summer, alleviating the impacts of flooding and providing shelter from extreme weather events. Vegetation in cities can also play a significant role in mitigating climate change impacts by sequestering greenhouse gases, and reducing energy consumption for cooling and heating.

Cities host numerous threatened plant and animal species. In Australian cities, more than 3 times as many threatened species are found per unit area than in rural areas (Ives et al. 2016). Some species are found only in cities, whereas others rely on cities for key food and habitat resources. The future of many threatened species will depend on actions to accommodate their needs within city boundaries.

Creating opportunities in cities for everyday interactions with nature provides an unparalleled opportunity to reconnect people with biodiversity, and expose urban residents to the myriad health and wellbeing benefits provided by nature. Furthermore, urban renaturing has the potential to connect urban residents with Indigenous history and culture, and create an avenue for preserving traditional knowledge and engaging urban Indigenous people in city planning processes.

The reasons for embracing nature in cities are compelling, but the pathways to achieve this vision are not always straightforward. An important first step is to reframe the way nature is considered in the planning process. Rather than considering nature as a constraint—a ‘problem’ to be dealt with—nature can be seen as an opportunity and a valued resource to be preserved and maximised at all stages of planning and design. It also requires a different conceptualisation of nature, where novelty is the norm and apparently scrappy bits of urban nature can have as much value as pristine nature reserves. The future of our cities may well depend on a new conceptualisation of urban landscapes, where nature can thrive and people can enjoy—every day—the remarkable range of benefits that nature can deliver (Figure BIO6).

Source: © Sarah Bekessy, GE Garrard & LM Mata, RMIT University, Melbourne; and RG Hobbs, University of Western Australia; all rights reserved

Public Spaces: 10 Principles for Better Urban Renewal

Our impressions of a city are formed mainly by the quality of public spaces. If they are not pleasant and preserved, or if they transmit a sense of insecurity, we will seldom return. Good planning of these spaces should be the rule, not the exception. In the series “Public Spaces,” originally published in Portuguese by TheCityFix Brasil, we explore different aspects related to public spaces that determine our daily experience in cities.

Nothing lasts forever without conservation and preservation. With cities, it’s no different. Different interventions in cities can alter built-up areas or public spaces to address social issues, environment or health problems, or even reactivate the local economy. In this context, the practices of renovation, requalification, revitalization and rehabilitation can be used to not only renew a city but help proactively solve a wide range of problems.

First, we need to differentiate terms that are often used synonymously but do not have exactly the same meaning. Briefly, “revitalization” is about recovering space or an existing construction; “renewal” deals with replacing or rebuilding and changing use; “requalifying” adds new functions while improving the appearance, and “rehabilitation” is restoring but without changing function. Each of these processes, therefore, generates different results. All of them, however, are linked to the same idea: to transform urban spaces in order to rejuvenate them.

Projects like these often arise from the need to solve economic, social or environmental issues, but are carried out in ways that make success difficult. They need community participation to be embraced but are often instead led by public-private partnerships that have few feedback mechanisms for community members to engage with. This is one of the most common criticisms of this type of intervention, in which large projects are conceived and constructed without any connection to the local reality.

New models of urban transformation should recognize that transformative change is no longer the responsibility of a single actor, organization, institution or sector. Change needs to be led by multi-stakeholder coalitions and movements, on the demand side as well as the supply side.

report by the Australia-based consulting firm SGS Economics and Planning presents 10 principles for urban renewal that take the public interest into account, based on case studies in cities like London, Sydney, Melbourne, Hamburg and New York. According to the survey, much of the criticisms of urban renewal projects are a result of actions undertaken without the perspective and contribution of affected communities. Finding ways to include more participation could improve success rates. The report focuses mainly on renewal; however, the principles also apply to revitalization, requalification and rehabilitation:

1. Create “Shared Value”

Urban areas do not belong to a single group or individual but should offer value to many actors. All those who are part of the broader community as a whole – from workers and tourists, children and students, to the underserved and investors – should benefit from urban renewal. “Ultimately, the ‘communities’ for whom the value is created to share, should be those with long-term interests, not transient stakeholders with a primary focus on value extraction and repatriation,” write the authors.

2. Plan With Input From All

Delivering this shared value requires engaging with communities. Planners bringing an intervention into an existing space should share their vision and include people in the planning from day one, or risk it being rejected. Decision-making techniques such as cost-benefit analysis should be explained and employed to also promote “non-financial values,” helping communities feel a sense of ownership. The researchers also suggest the creation of a common platform where information about the process and the progress of the project can be shared transparently.

3. Build a Long-Term Vision

In any extensive process of urban renewal, the initial goals of the project may change over time. Even so, a long-term vision should be locked in and changes for the sake of short-terms gains resisted, with flexibility growing as the timeline extends further into the future. “A commitment to the public interest and shared value needs an inclusive approach, and future development stages should have the flexibility to be able to adapt to market and social changes,” write the authors.

4. Agree on Non-Negotiables

Non-negotiation issues should be clearly understood by all stakeholders. These could include respecting existing lease terms, fixed quotas for affordable housing or protecting open spaces. The rights of renters and leaseholders should be guaranteed and stakeholders agree to a common set of design standards.

5. Agree on a Financial Profile

Studying how the space to be renovated is expected to yield from a financial perspective not only serves to set parameters for the project’s development options but is also critical to whether the public’s interests will be met. There are many options available to both provide returns on government investment in underserved areas but also safeguard communities from potential negative side effects, like rising taxes, and encourage a handoff to private developers in the future.

6. Establish Clear Development Goals

The planning process should develop and affirm clear objectives, not just desired outcomes. The best goals will be specific and measurable and anticipate the physical, economic and social results of the project.

7. Establish Options to Achieve Development Goals

There are often multiple options for achieving the same development goals and they should be compared to one another as well as to baseline scenarios of what might happen without any intervention. The process will create “a much clearer picture of marginal benefits and costs associated with any particular development option,” the report explains.

8. Incorporate a Sense of “Localness”

Local characteristics and peculiarities should be captured and incorporated into the new project. These details may come from local standards, services offered in the region, the environment, the climate or other socio-cultural specificities. Finding ways to assimilate a sense of the local into the project will help people identify with it, separate it from other similar projects and generate community acceptance.

9. Evaluate Options With the Goal of Maximizing Net Community Benefits

Cost-benefit analyses are often viewed with scepticism, but the report notes there are well-documented techniques that allow for the inclusion of things communities care about most, like open space, social capital and heritage. Finding ways to incorporate them into a cost-benefit analysis is important for avoiding the scenario where “financial considerations or otherwise vague community aims to end up dominating choices between options.”

Macquarie Mall Redevelopment

10. Align the Procurement Model With the Planning Vision

Finally, the governance, implementation and contracting trajectories – how the project is actually carried out – should align with the unique vision laid out during the planning phase. Procurement targets should bespoke, rather than using “off-the-shelf” options. This may mean a greater role for the government as a developer in the early stages before handing off to private sector developers later.

“These principles are not locked in place but are guiding principles to ensure urban renewal benefits the widest community possible,” write the authors. “The renewal of strategically important urban sites must have the needs of communities, both social and commercial, at its core.”


Citygreen Projects

Source: Paula Tanscheit is the Communications Analyst for WRI Brasil Sustainable Cities.

Citygreen’s Projects, a team of experts in all areas to manage your urban renewal project from start to finish

Citygreen Projects is driven by a clear set of values, a passion for exceptional project outcomes and an enduring commitment to innovation.

What we can bring to your urban revitalisation project:

  • Concepts and modelling
  • Budgeting and feasibility
  • Technical design and drafting
  • Documentation and contract admin
  • Project management and scheduling
  • Construction and quality control
  • Commissioning and maintenance

What is Citygreen Projects?

Citygreen Projects is your multi-disciplinary project partner to assist you in urban revitalisation projects through all phases, from conceptual modelling, budgeting, and community engagement right through to design, documentation and then final delivery of construction works.

We work together, blending our expertise and knowledge across urban planning, urban design, and landscape architecture to meet your needs and aspirations.Our advice, services and solutions are well-considered and balanced. We respond decisively to every job and every challenge, ready to help realise a successful outcome that is workable, sustainable, and achievable. We pride ourselves on integrity and commitment and believe in explaining the realities of every situation.

What services does Citygreen Projects offer?

Citygreen Project’s role is the creation of sustainable places for people that enrich community life, provide joyful, memorable, and worthwhile experiences, and serve the natural environment.

Citygreen Projects works closely with Citygreen’s DesignStudio, a dedicated and experienced group of design professionals providing services in master planning, plans of management, design for public domain, parks and open spaces, strategy and policy for recreation, open space and public domain, and planning and design for multi-residential developments and estates.

Our process is multidisciplinary, tapping into the extensive experience and insight of experts across our practice. We take an inclusive approach, involving clients at all stages of a project to ensure their needs are met, providing education and insight wherever needed.

Who does Citygreen Projects work with?

We work with clients (particularly LGA’s) throughout Australia and New Zealand, balancing commitment, creativity, and innovation with award-winning experience. Creating great cities and places to live and work requires an ability to respond to urban and regional development complexity. Our collaborative approach integrates multiple stakeholders and complex interrelationships.

Our services extend across private and public sectors and all scales of projects, from master-planned communities to intimate and engaging interior spaces. Citygreen’s DesignStudio, a team of architects, designers, planners, engineers and environmental scientists, share the technical knowledge and the latest digital tools and resources to bring imaginative thinking to solve clients’ challenges.

Why should I get Citygreen Projects to manage my next Urban Renewal Project?

Citygreen assists you in undertaking urban landscape projects from start to finish, so you don’t have to spend a lot of time and budget managing multiple contractors. At Citygreen, we have been researching and developing best practise methodologies internationally for decades to help plan, plant and maintain trees in the city and create green space in urban environments.

Citygreen Projects understands how towns, cities, and region’s function. Our aim is to work with you to make them even better, streamlining the planning and design process to ultimately deliver successful, compelling solutions.

I have a vision for an urban development project, what are the next steps?

Book a free online workshop to learn more about Citygreen Projects. This interactive workshop covers everything from creating large healthy tree canopies faster and more predictably to how to integrate living green wall systems, to incorporating stormwater management and increase the liveability and sustainability of our cities for generations to come, based on case studies, industry research, structural and civil engineering considerations.

Book Your Online Workshop

What are the Benefits of Green Walls?

Green walls are one of the latest trends in interior design and with good reason. They are beautiful, healthy, and the benefits far outweigh the costs and maintenance.

If you’ve been following some of the recent building trends, you may realise that outdoor and indoor green walls are now popular. There’s more to the popularity of the walls than just a great aesthetic look. In fact, there are several benefits of having living walls on the inside or outside of your building. Learn more about those benefits and how having a green wall can help you.

1. Purify the Air

You’ve probably heard the Amazon jungle referred to as the “lungs of the earth.” That’s because the immense, dense foliage of the Amazon jungle converts carbon dioxide into oxygen. And while we all benefit from the chemical process that plants use to create oxygen, there is more that we can do to ensure that our household air is clean and oxygen-rich. Enter green walls.

One of the most significant benefits of a green wall is to improve the quality of your indoor air. Approximately 25% of carbon emissions made by human activity are absorbed by plants, and living walls contribute to that absorption. Plants on the wall filter toxins in the air and convert carbon dioxide to oxygen. In doing so, they create a healthier environment for you, your family, and your guests.

Have you ever noticed how an enclosed room or home can become stuffy? The more people and animals that you add, the less breathable the air is. During milder days, you can open a window, but that means shutting off your HVAC or running higher electric bills. An interior green wall can help offset the oxygen use of humans and pets in your home. And as an added benefit, your improved air quality means less eye irritation, fewer headaches, and reduced incidents of illness. If the wall is located inside a workplace, the employees are more productive and will take fewer sick days.

2. Decrease the Ambient Temperature

Heating and cooling a workspace can be expensive, and during severe winters and hot can take a significant chunk out of your profit. There are many things you can do to reduce these bills, from adding insulation to sealing doors and windows to replacing your HVAC system with a high-efficiency unit. But there’s another simple way to lower your energy bill: living walls. The plants absorb and reflect some sunlight, which cools down the air. As a result, you spend less money on your cooling bill.

Even an outdoor wall decreases the ambient temperature. Many cities have the heat-island effect. This is where the heat given off by machinery, vehicles, and buildings get trapped in a certain area and drive up the overall temperature. Outdoor plant walls decrease the outdoor temperature, which makes visitors more comfortable.

3. Decrease Noise

Have you ever noticed how a carpeted room tends to be quieter than one with a tile or wood floor? That’s because sound reflects off of flat, non-porous surfaces. Things like curtains and rugs can make a noisy room quieter. Plant walls have much the same effect. Sound vibrations are absorbed by the plant leaves, rather than being reflected back into the room.

A plant wall absorbs approximately 41% more noise than a traditional wall. Outdoor walls reduce noise from traffic, aircraft, and construction activities, and any other noise that you experience living in an urban centre. Indoor green walls can make rooms less echoey. Whether the wall is inside or outside, it works as an affordable and artistic sound barrier.

4. More Productivity

There are many tactics that employers can attempt to improve worker morale. One of those is changing or improving the decor of the workspace. Workers tend to appreciate significant improvements to the quality of their work environment. After all, they’re spending a significant portion of their days in the same location. If your goal is to improve worker productivity, a living wall is a rapid and affordable method of increasing productivity. Employees respond positively to more greenery in the workplace.

5. Make a Building More Fire-Resistant

As you might expect, plants contain a significant amount of moisture. That moisture makes them naturally resistant to fires. This might seem counterintuitive when you consider brush fires or forest fires, but those usually occur after long dry spells. Plant walls remain lush and green all of the time. By adding a living wall to your building, you make it more fire-resistant.

6. Extend the Life of Your Wall

Your walls are exposed to sunlight, wind, rain, and extreme temperature changes. Over time, the elements destroy your wall. But a living wall protects your structure from direct damage. The life of your wall could be extended by years.

7. Give your Building More Value

To make your building more valuable, you can make several changes. However, those changes often come at a high cost. You may need to spend thousands of dollars to get a small return.

When you install a living wall, you make your building more valuable. The natural look is coveted by many buyers. Furthermore, energy savings gives you even more value. A living wall is an investment that immediately starts paying for itself.

8. Create a Community Feel

A green wall attracts people and lightens the mood. It brings together neighbourhoods and communities while decreasing aggression and vandalism. To help your building bring together your community, you should consider a green wall.

Outdoor and indoor green walls come with multiple benefits. If you’re interested in getting started, you should start doing your research and planning for your wall.

Be Part of the Green Revolution

Indoor and outdoor plant walls protect our environment. While it might not seem like one or two walls can do much to fight climate change, it can help to offset your individual or your company’s carbon footprint. Plant walls may be one of the only truly guilt-free indulgences that are left. Add a little green to your life with a beautiful plant wall.

What’s the Magic Number? 31.4 Million.

To advance Tree Equity and help slow climate change, we need to plant 31.4 million trees annually in U.S. urban areas.

By Ian Leahy, American Forests’ Vice President of Urban Forestry

An urban neighborhood in Providence, Rhode Island with a tree canopy of just 9%. Photo Credit: Eben Dente / American Forests


The challenges of an urban street tree

By: Sylvia McNeill, ISA Board-Certified Master Arborist RM-7117B © 2021 McNeill’s Tree Service

Talk about a tough life.  Before I start on what could well end up being a rant, let me state:  there are no trees “native” to the built environment.

When discussing the built environment, we are referring to anything and everything created by people.  It is contrived and manipulated.  The complete antithesis to where trees naturally grow.  And yet we want, and indeed need, them in our proximity.  If you doubt that, simply go someplace where there are no trees or plants whatsoever and then transport yourself to a place with them.  If you prefer the area without, believe me, you are in the minority.

Our cities are “built environments”.  To our credit, we keep trying to incorporate trees and plants within these areas to provide some kind of respite from the harsh concrete climate.  Are we successful?  According to some studies, not so much, suggesting the typical street tree mean life expectancy is 19-28 years.  However, it is further suggested the tree population half-life is 13-20 years, meaning for every 100 trees planted, only half of those will make it to 13-20 years.  (Roman 2014)

With all our modern technology and innovations, we are having a hard time achieving longevity in our street trees within urban areas compared to cities of the past.   Here in our area of Montana, some of our cities have street trees that are over 80 years old, some even older.  But as they decline and have to be removed, their replacements are having a hard time establishing and surviving.  So, what gives?

Modern cities are far different from cities of the past.  In the past, streets tended to be wider and unpaved.  Rainfall would be absorbed by the entire street area and any tree planted near that street would likely be able to access that water.

Streets now are paved where stormwater drains may be designed to bypass roots.  One of the many ecosystem benefits touted for trees is their ability to mitigate stormwater runoff…if it is channelled away from their roots, how are they to perform this job?

There are often paved sidewalks on one side of a tree with the parking area and adjacent street on the other side, again all paved.  These areas between the sidewalk and street often referred to as boulevards, may be very narrow or very wide.  Trees fortunate enough to be planted in wide boulevards have a much better chance of survival.  The caveat here is “if the quality of soil is sufficient to their needs”.

A lovely Gleditsia triacanthos ‘Sunburst’ – Sunburst honeylocust planted in a wide boulevard

The quality of soil in boulevards can vary from not bad to really awful.  With the construction of surrounding infrastructure and housing, all manners of debris may be buried in this area.  This may include concrete, building debris, contaminants – basically, anything that needed disposed of during construction could have been tossed here.  It may be rocky, it may be silty.  It may be seriously compacted, which restricts root growth and water drainage.

Trees planted in the narrower boulevards are subject to conflicts with the sidewalk and streets as their roots grow.  As sidewalks require repair, roots are often cut to the detriment of water uptake or even stability of the tree itself.

Roots were severely cut back to enable sidewalk repair. Tree declined to a point where removal was mandated.


Sometimes trees are completely surrounded by concrete or grates may be used to distance the trunk from the concrete. Unfortunately, if the grates aren’t maintained, they can also damage the tree.

Photo on the left example of poor tree grate maintenance. Citygreen’s Duraplate tree grate (on the right) incorporates specifically designed features for easy maintenance.

Another challenge experienced by city street trees is the pruning required to keep them above vehicle and pedestrian traffic.   Merchants do not like their signage blocked and it is important to keep trees from blocking clear view triangles on street corners to ensure public safety.

Please remember, the trees did not plant themselves.  Very few are volunteers in these areas.  It is up to the people who plant them to select a species that is hardy enough to have a reasonable chance of survival in the site selected, that the site is actually suitable for a tree at all (some sites simply should not be planted), to ensure the tree has the potential structure to minimize pruning needs (which is a factor not only in the health of the tree but the expense for management), to ensure planting is done correctly and that aftercare is prearranged and committed.  These last two conditions are the most common reasons why trees do not survive the establishment period for any area, let alone for the challenges faced by street tree selections.

Additional challenges include damage by vehicles, vandalism, and extreme weather conditions enhanced by the infrastructure around them.  I often think trees survive in spite of us, not because of us.

These photos show the opposite sides of the same tree taken on the same day.


We need to work on being better stewards because we need trees.  There is no need to quantify “ecosystem benefits”.  All you have to do is remember without plants, we (humans) would not exist.

References: Roman, Lara A.  (2014) How Many Trees Are Enough?  Tree Death and the Urban Canopy.  Scenario 04:  Building the Urban Forest

How to promote deeper root growth and drought tolerance

Best Tree Root Development

Sufficient oxygen, water and nutrients are essential for healthy root growth and therefore healthy trees. If soil gets too wet, the voids between soil particles become filled with water and the root hairs cannot absorb oxygen. Over time the roots ‘drown’ which eventually may also kill the tree, through lack of the required water and nutrients.

The water from efficient tree irrigation is required not only for all the biochemical processes involved in photosynthesis, respiration and transport but also for mechanical support to leaf and stem tissue.  Insufficient (or inefficient) tree watering will result in loss of leaf turgor and a consequent reduction in new shoot extension. Eventually, this will lead to die-back and, if not remedied, the loss of the tree.

Oxygen may also be available at depth if the soil is not compacted and the action of earthworms has created tunnels through which oxygen can flow. Tree roots will grow near the surface unless adequate water and air are available below ground.

How does it work?

One method for providing both the necessary water and air to the tree roots involves the use of a perforated flexible piping system. At the time a tree is being planted, the pipe may be looped around the rootball within the immediate rooting zone of the new tree, and also in the outer rooting zone, looped throughout the root cell matrix. The pipe is then connected to an inlet located at the tree pit surface. This method may be adapted for use beside roadside verges and open space tree planting or in heavily-trafficked areas.

The water inlet

The inlet enables a water hose to be attached when water is needed. The rest of the time the pipe, being looped in a circuit, allows air to flow passively through the system and around the roots of the tree. Changes in air pressure above ground are also accommodated. This arrangement enables long deep watering over the entire root system and the opportunity for the soil to dry between watering, which is better for trees than frequent light watering.


Snorkil™ RootRain

RootRain™ Urban is a large capacity irrigation system with a fixed non-removable grid inlet. The grid allows water and air through but prevents ingress of litter and debris.

Suited for: Roadside verge and open space tree planting. 

Snorkil™ Rondo & Plaza Series

The Snorkil™ Rondo (round inlet) and Snorkil™ Plaza (square inlet) series have been specially designed to interlock with our range of integrated tree grilles or be set in the pavement to provide an attractive and durable way of maintaining aeration for tree root systems.

This provides a tamper-resistant system that will also prevent the inlet from sinking as a result of any soil settlement around the tree.

Suited for: Integrated tree grilles or to be set in the pavement.
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"I reviewed all the previous projects that we have installed in the past couple years using your product and I can happily report back that we have 0% mortality in the soil cells, which is incredible!"

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