The rise of Urban Forestry

There is a living, breathing ecosystem around us that deserves our attention

By the year 2050, the United Nations estimates that about 68% of the global population will live in cities. Vancouver alone is expected to welcome an additional one million residents, many of whom will want places to recreate and find refuge outdoors and close to home.

While urbanization is impacting everything from the hydrology of our planet to the number and intensity of extreme weather events, it also affords greater housing density and economies of scale that rural communities lack. Housing density often concentrates demand on public resources, such as parks, sports fields and other urban and wilderness spaces. Meeting public demand for these spaces, while maintaining their health and resilience in the face of mounting pressure from climate and land-use changes, is no small task.

“If you just ignore natural areas, they become covered in Himalayan blackberry and other invasive species,” says retired urban forester Owen Croy (BSF’87).

BC presently has over 800 alien plant species, more than 175 of which are invasive and harmful to the local environment.

“We need to pay close attention to the intrinsic value of the urban canopy and natural areas – describing them, mapping them and determining whether they need to be protected and to what extent.”

Owen has an impressive professional background in urban forestry. In the 1980s, he worked with Agriculture and Agri-Food Canada, then spent over 25 years as an urban forester with the City of Surrey. Currently, Owen is an instructor with the Municipal Forestry Institute and an Adjunct Prof. with UBC Forestry.

From a bird’s eye view, Owen believes that the urban forestry profession’s number one goal now is to “find a way to communicate important messages and educate people from all walks of life about the benefits of the urban tree canopy, urban parks and natural areas in and around communities.”

Canadian roots

The history of urban forestry in Canada dates back to 1955, when Danish forester Erik Jorgensen arrived in Ontario with a keen interest in fungi and plant pathology. The rising star in forest pathology received a Master of Forestry from the Royal Veterinary and Agricultural College in Copenhagen, Denmark before being offered a position as a research officer with the Dominion Forest Service field laboratory in Maple, ON.

Erik took up arms against Dutch Elm Disease (DED), an invasive fungus that was killing elms in the metropolitan Toronto region and is easily spread by infected beetles from tree to tree. But the road to controlling the spread of DED seemed insurmountable without buy-in from local government and community members.

Erik realized that a new area of specialization was needed through which to frame the problem and train a workforce with the knowledge and skills to tackle invasive species, such as DED, and other issues affecting trees in urban areas. Dubbing it ‘urban forestry’, Erik defined the specialization as the cultivation and management of trees for their environmental and societal benefits. With Erik’s input, the University of Toronto began offering an urban forestry course in 1965.

Urban forestry at UBC

In 2015, UBC Forestry became one of the first forestry schools in Canada to establish an urban forestry degree program. The program is one of the largest in North America, and its Urban Greenspace Management minor became the first urban forestry credential to be accredited by the Canadian Forestry Accreditation Board. Future graduates of this minor will meet the academic requirements for RPF status in any of the eight Canadian provinces that have a professional forestry association.

UBC Forestry now offers both a Bachelor of Urban Forestry and a Master of Urban Forestry Leadership, along with a wide range of urban forestry courses in both greenspace management and landscape and recreation planning. For example, Asst. Prof. of Teaching, Andrew Almas, teaches ‘Greening the City’, ‘Urban Forest Governance’ and ‘Urban Forestry Field School’, among others. Many classes are hands-on and involve field work. Led by UBC Forestry Lecturer and Director of Urban Forestry Programs, Sara Barron (MLA’08, PhD’19), UBC Forestry’s urban forestry programs have continued to expand, establishing a global reputation for excellence in this space.

“Students want to learn about urban forestry because they see the need for this specialized knowledge in communities,” notes Sara, whose research has focused on urban green spaces. In a 2023 study, Sara draws connections between urban natural spaces and youth social and mental wellbeing.

“I can see demand for this emerging discipline continue to grow with the expansion of cities, which require more climate-friendly solutions to urban densification.”

A diverse field

Until recently, urban forestry was a term unfamiliar to many Canadians. Now, however, metropolitan centres are turning to their urban forests to address issues ranging from human health to storm water mitigation, wildfire preparedness and community tree planting programs.

Urban foresters survey tree inventory for disease and pest detection and control. The profession has also evolved into the management of peri-urban areas adjacent to cities, consulting with other levels of government, launching public awareness campaigns, partnering with non-profits, controlling invasive species and protecting habitats for native plants and animals.

The career path of Joe McLeod (BSF’01), a landscape architect, arborist and manager of urban forestry with the City of Vancouver, exemplifies the broad skillset in demand within the specialization. Over the years, Joe has amassed professional experience in the fields of silviculture, arboriculture, wildlife habitat enhancement, woodlot management planning and landscape architecture.

“My primary obligation with the City of Vancouver now is risk management,” says Joe. “This ranges from managing decision-making related to wildlife habitats for nesting birds to removing danger trees and responding to our political commitments, such as bylaws and policies.”

Human and ecological health

Many of the drivers of change in urban forestry are born of necessity, government policies and on-thejob problem-solving. Others are being developed at educational institutions by leading thinkers in the field, such as members of UBC Forestry’s Urban Forests Research Hub (UFRH), which supports cutting-edge research to advance the science of urban forestry and realize sustainable urban ecosystems.

The research of UFRH member and UBC Forestry Prof. Susan Day digs into how the soils below urban forests impact ecosystem services, such as groundwater and stormwater management. Her insights have helped to set the soil sustainability standards of building developments for private companies and public officials.

UFRH member Asst. Prof. Lorien Nesbitt (PhD’18) researches environmental justice and human health and wellbeing in urban settings.

“Studies have shown that exposure to nature can support better heart health,” Lorien says. “Nature can also increase the amount of time people spend engaging in physical activity.”

Green space helps people cool down during times of extreme heat, such as heat domes, Lorien adds. It is also a valuable arena for making social connections.

“Exposure to green space has been linked with improved mood and mental health; lower stress hormones, such as cortisol; and improved microbiome conditions, which influence such things as asthma and other respiratory illnesses.”

Research led by UBC Forestry Adjunct Prof. Matilda van den Bosch , in partnership with Lorien, has found that exposure to vegetation in residential neighbourhoods can improve early childhood development outcomes.

“This is really important as we think about designing our cities in ways that can support healthy development in children, particularly among under-resourced families,” says Lorien.

Coexisting with nature

UBC Forestry Asst. Prof. in Urban Ecology and Urban Wildlife, Sarah Benson-Amram , examines how urban mesocarnivores – such as raccoons, skunks and coyotes – are adapting to their newfound environment.

Sarah collaborates with neuroscientists to understand animal cognition and behaviour. She often advises municipal government workers on how to reduce humananimal conflict through a deeper understanding of how animals have gained brain power and brawn to break into garbage cans and prey on small pets, as well as approaches to promote amicable coexistence.

of these animals puts all outdoor food sources on the menu, including food dishes for pets, compost bins, gardens and bird feeders, any of which can lead to human-animal conflict.

“Since cities are expected to continue expanding in the coming decades, I anticipate a parallel growth in human-wildlife conflict,” Sarah adds. “ But, there are many things that we can and should do to promote peaceful coexistence with wildlife, such as making it harder for them to eat human food.”

Getting citizens on board

In many ways, urban forestry’s success hinges on the involvement of multiple stakeholders and partners, including businesses, various levels of government and citizens.

“We’re seeing more human-wildlife conflict as cities expand and animals become more accustomed to us,” says Sarah.

For example, in January 2021, the BC Conservation Officer Service and Vancouver Park Board rangers closed part of Stanley Park in Vancouver following multiple reports of aggressive coyotes and attacks. As a result, several coyotes believed to be responsible were euthanized.

“As the saying goes, a fed bear is a dead bear,” says Sarah. “This is why we don’t want wildlife to get too comfortable around humans.”

Using night-vision cameras, radio frequency identification tags and, increasingly, artificial intelligence to aid in image analysis, Sarah and her research team have been wowed by the ability of raccoons to solve feeder puzzle boxes to retrieve the food secured within. The high-intelligence

UBC Forestry Prof. Emeritus Stephen Sheppard (MSc’78) has worked alongside local government staff on urban sustainability projects, such as investigating energy alternatives for single-family homes in the District of West Vancouver, BC, and developing a Coolkit for Oak Bay, BC (connect.oakbay.ca/coolkit).

The Coolkit program that Stephen and the Collaborative for Advanced Landscape Planning research group developed teaches residents simple steps that they can take to green their neighbourhoods, save energy, calm traffic and promote pollinators, among others. The program champions such initiatives as scaling-up tree planting and the stewardship of both trees on public streets and private lands.

In the face of a warming world, cumulative efforts by municipal governments, private companies and citizens to implement science-based urban greening and sustainable landscape design recommendations can significantly reduce a community’s greenhouse gas emissions and cool entire neighbourhoods. For example, approximately 88% of Vancouver’s trees are on public lands, such as Stanley Park; however, 57% of Vancouver lands are privately owned, notes Joe. To reach the city’s goal of 30% tree cover from the present 20%, staff members are looking to private landowners to help close the gap by planting more trees on their properties.

“Putting money and resources towards answering this question is more likely to produce green spaces that better serve the health and wellbeing of all members of a population.”

The National Healing Forests Initiative (nationalhealingforests.com) and the Vancouver Urban Food Forest Foundation (vufff.org) both support the co-creation of anti-colonial and healing parks and gardens, addressing the reality that green spaces often reflect colonial aesthetics and histories of oppression in their design and current uses, notes Lorien.

“There are many different ways of understanding the natural world and our relationship to it, along with different ways of engaging in that relationship,” says Lorien. “We need to be open to those differences.”

What degree of tree cover might be required to provide communities with optimal levels of ecological services and health benefits is a topic for further research and planning, says Melissa McHale , an urban ecologist and UBC Forestry Assoc. Prof. of Urban Ecology and Sustainability.

Doing so may boost not only citizen engagement in the future of green spaces in communities, but the equitable access to and sustainability of those spaces.

Science-based data

Working alongside municipal governments, Melissa’s research has influenced government decision-making on how to sustainably green urban landscapes.

“On the whole, municipalities want to manage for their citizens, and on-the-ground data matters,” states Melissa. “Information that is specific to a place helps decision-makers across different departments within a city get on board to understand the ‘why’ behind a given management strategy.”

For her September 2022 study, Melissa and her research team assessed the summertime electricity consumption for cooling 21,048 single-family homes in a semi-arid city in Northern Colorado. While prior research linked greater energy consumption reductions to shade trees located on the west side of a home, Melissa’s study found that shade trees on the east side resulted in greater energy savings.

In another study, Melissa and other researchers found that people in a semi-arid environment who had trees in their yards used less water on their lawns and gardens.

Municipal water conservation, utilities, transportation, forestry and natural lands management departments have different foci, but data could help them identify opportunities to collaborate to meet shared climate change objectives and improve residents’ quality of life.

“If we are going to keep putting people in tiny spaces and stacking them on top of each other, we have to give them somewhere safe to go outside,” says Melissa. “If all you see when you walk out your front door are impervious surfaces, such as concrete and asphalt, it’s going to be a miserable existence.”

Under-resourced communities are less likely to have access to green space and are often excluded from its design and stewardship; but, research has found that these communities derive more health benefits from interacting with urban forests.”

Environmental justice

In the bid for greener, healthier cities, researchers are calling for justice in urban greening.

“Under-resourced communities are less likely to have access to green space and are often excluded from its design and stewardship; but research has found that these communities derive more health benefits from interacting with urban forests,” says Lorien.

“It isn’t optional to put running water in our homes, but it has been seen as optional to plant or care for trees in our neighbourhoods,” she adds. “Trees should be seen as a matter of equity and justice.”

Working with her students in the Urban Natures Lab, and other co-investigators at UBC and internationally, Lorien’s research has examined inequitable distributions of urban vegetation in multiple cities across North America, including in the Lower Mainland. Her team has also analyzed the risk of gentrification associated with urban greening, a potential issue of concern when trying to correct inequitable access to green space.

The accessibility and design of urban parks to ensure that these valuable public spaces can be enjoyed by all members of the community is highlighted in the research of Asst. Prof. of Urban Forestry, Keunhyun Park

After analyzing drone data of urban park usage, Keunhyun created a demographic map of park users and activities. Data on users’ age, sex and whether they were sitting or running in a park, among others, can paint a picture not only of park users but also of people who might face barriers to park access.

“Many neighbourhood parks in suburban areas are underused,” says Keunhyun. “This often comes down to issues related to park location and design, as well as their connectivity to surrounding neighbourhood spaces.”

In Vancouver, one reason for park underutilization is that many are located in affluent, low-density neighbourhoods that are difficult to reach by transit – either due to absent or infrequently scheduled transit stops or long travel times.

Better access and utilization could be achieved through the co-creation of park space with representatives from diverse populations, cultures and under-represented ways of being and knowing, says Lorien.

Ultimately, parks are funded by citizens. And, how we engage with and manage our landscapes can contribute to not only the health and wellbeing of communities, but the planet as a whole.

Explore this topic more by registering to attend the Urban Forestry Webinar on June 15, 2023 from 12:00pm-1:00pm: forestry.ubc.ca/events/urban-forestry-webinar