What do Canadians Value About Urban Trees?

May-June 2013

As city homeowners and other private property owners plant and care for trees, their values can dominate the decision processes. But when trees are planted and cared for on municipal land, then the views of the entire public become critical. A public that is upset about management of the city’s tree canopy is unlikely to lend much support to urban forest managers when they go to council for continuing or additional support for their work.

The role of values in management can be argued this way. First, management is guided by objectives. These set directions for the things that are important in the managed system. We can call these important things “values,” which is the way they are described in the Canadian Standards Association Z809 standard for sustainable forest management. So, if values are the essential subject matter of management objectives, it stands to reason that managers need to be diligent and careful about understanding and selecting values to be used to guide management.

How Can We Discover Public Values?
As with most topics in social science research, there are several methods one can use to get at the central questions. We have used five methods to elicit values-related information from urban people in the past few years:

1. Field with diaries (and usually with subsequent focus groups). With this method, we take small groups of people (5-15) in vans around to various urban locations that have a diversity of tree canopies. So far, we have used places such as a tree-lined residential street, a busy commercial strip, a botanical garden, a pocket park, a large naturalized woodland, and a recreation park (see above photo). Participants quietly experience the setting and write their thoughts into a diary provided by us. A focus-group discussion follows lunch, and we then collect the diaries for analysis. We have implemented this method in Calgary, Winnipeg, Fredericton and Halifax.

2. Interception surveys on city sidewalks. Using a short questionnaire, researchers invite passers-by to stop for a brief conversation about trees in the city. We have done such surveys in Winnipeg, Fredericton and Halifax.

3. Online surveys. In association with green-space planning at Dalhousie University, we implemented an online survey to canvass the views of members of the university community – students, staff, professors, and alumni – about trees on the campus.

4. Walkabout interviews. Rather than interview someone in the home or office or in a café, we have chosen to tether a recording device to our subjects and go for a stroll through the streets (or campus or woodland) for a chat about trees. Using this approach, answers to questions become richer because they can be prompted and guided by what both respondents and the interviewer see during the walkabout. We have done such walkabout interviews on the Dalhousie campus.

5. Photo-based interviews. In this method, participants are given a disposable film camera and asked to take pictures of trees in the city according to their own motivation in choice of scenes. Then, once the camera has been returned and the photos developed and printed, the researcher returns to each participant with his or her photos and has an interview about urban forest values based on the scenes in the photos. We have used this method only in Winnipeg so far.

Our Research Findings
Our results are still in various stages of analysis and reporting, but we can share the following insights.

From the interception surveys, some common themes have emerged. While the specific rank orders of values’ relative importance varies among the three cities, the results show that some values are key across the board: (a) aesthetics (the appeal of trees to the senses); (b) air (freshening of the air); (c) shade (for human comfort and health); (d) environmental quality; and (e) oxygen production. Attaining a top-seven spot in at least two cities is sense of place and naturalness (which we interpret to mean bringing desirable natural features to enhance the built environment).

The responses summarized above were totally unprompted – we did not provide a list of choices, but rather just asked why trees were important to the people who said that they are (which was the vast majority of respondents). In the online survey at Dalhousie, we prompted people with a list, but also encouraged them to fill in a blank slot if anything important to them was not on the list. The top responses here were carbon sequestration and storage, positive psychological effects (rather like well-being), wildlife habitat and aesthetics. At first we were surprised by the strong response about carbon, but we think there might be a slight bias from the position carbon had in the listing (it was first), and also we believe that a university crowd, reasonably well sensitized to the issue of climate change, might have been tuned up to choose this option for global sustainability considerations.

Finally, let’s look at the trends coming from the field tours, a method we cherish because it gives our research subjects considerable time to reflect on trees and to discuss their thoughts and feelings together before we disconnect with them. In the work done by Shawna Peckham in Calgary and Halifax, she found that trees and other elements of natural vegetation were pivotal in people’s development of an eco-consciousness. She also found that her respondents were much more prone to write and talk about the aesthetic and psychological values of trees in the city than they were about ecological and economic aspects. Shawna’s findings are nicely summed up in this sentence from her thesis:

“Urban trees were mostly valued by respondents because they provided peacefulness, comfort, escape, beauty, naturalness, a connection to nature, biodiversity, a sense of history, and a preferred environment for family and community.”

In our Winnipeg work, Jaclyn Diduck explored the theme of transformative learning – what did respondents learn about, in relation to trees and the urban forest, that might have transformed their behaviours later in life. Values are important to our education and learning because when we are faced with a decision, our values are the driving force behind our actions. By simply partaking in the field tours, respondents began to re-think their own beliefs, starting the transformative learning process. Respondents explained to her that many of their parents had a “certain reverence for nature” which engraved an early appreciation for the trees. A few also noted that they learned about the urban forest through a long association with it since, for them, it was the only nature they connected with as children – their families could ill afford trips out of the city. With learning, respondents want to act to protect the trees with which they have positive associations. Thus, public participation that focuses on people’s learning can have positive impacts on the management of local urban forest.

Implications for Management
Our examination of the management objectives in urban forest management plans across Canada reveals a preponderance of two themes. The first is a general drive to increase overall forest canopy cover. Most urban forest managers want more trees in their city environments, especially in places where the canopy coverage is remarkably low (e.g., commercial and industrial districts, new housing developments). The second theme is a justification for improved urban forest management programing on the grounds of quantitative values – the things we can calculate, such air-quality improvements, storm water attenuation, carbon sequestration and storage, energy conservation and others. General acknowledgement is given to the ways trees are important to people’s social and psychological well-being, but that is about as far as these topics go in the documentation.

From our studies, we are beginning to understand better what is on the minds of the urban citizens about trees in the city. Most of those thoughts are not about the things people can calculate. The thoughts are dominated by how trees make people feel. Increasing canopy cover will probably help here, especially in neighbourhoods bereft of trees, but perhaps many management decisions would be different if how people value trees was as influential as the things we can calculate. Would we change our species selections in new plantings? Would we alter our street-tree spacings and alignments? Would we re-allocate programmatic efforts among large parks, pocket parks and street-tree programs? Would we trim trees differently? Would we favour more-naturalized tree communities?

We do believe that the things we can calculate are extremely important too, and perhaps people don’t mention these topics in studies such as ours because they are less obvious to people than their own feelings. We argue that a better balance between the quantitative and qualitative value sets is needed. Our aim here is not to prescribe solutions, but to help managers re-consider the important values in the context of sustainable urban forest management.

Encouragement for Research Collaboration
Each town and city’s urban forest is unique, as is the complexion of its residents. Winnipeggers cherish their elms in a unique way, and the people of Whitehorse may well connect to the birches on their city streets. One good reason for not prescribing generic solutions about urban forest values and their role in sustainable urban forest management is that each town and city needs to determine its own unique urban forest future. Perhaps for some locales, that future is well settled and agreed upon by the professionals, citizens and politicians. In others, there may be cause for serious re-consideration of the ways things are done.

What we can say with confidence across the board is that formal research is a far better way to develop reliable knowledge about public values for urban forests than assumptions, guesses and the occasional townhall public meeting. Every Canadian province has a cadre of competent social scientists – at universities and in consulting firms, for example – who can implement formal research methods to help urban forest managers get better insight into urban forest values. We strongly encourage the management community to engage the research community in partnership arrangements. These not only will benefit both parties as they pursue their respective ambitions, but will doubtless foster more-sustainable urban forests across our country.  

Authors, etc.
Peter Duinker, Camilo OrdóZez, James Steenberg, Jaclyn Diduck, Stephen Cushing, Shawna Peckham, Tom Beckley, John Sinclair (members of the Canadian Urban Forest Research Group). Peter Duinker, Dalhousie University, presented a workshop at CUFC10 last fall in London, Ontario.

Further Reading
Canadian Urban Forest Research Group. 2013. In Support of Trees in the City: A Message for Municipal Councillors, Developers and NGOs. Canadian Urban Forest Research Group, School for Resource and Environmental Studies, Dalhousie University, Halifax, NS. Accessible at www.canadianurbanforest.ca.

Managing to resolve issues or satisfy values?

In our workshops across Canada on urban forest values, we have heard professionals refer to negative values, or, in other words, the things about trees people say they dislike. We do not call these negative values, because we see values as only positive. These are issues or concerns. Our position is that we can redefine an issue or concern so as to identify the value that may be compromised without specific actions. Here is an example. Suppose someone complains about the smell of a local female ginkgo tree. That would be an issue. What is clear is that the complainant values an environment with either pleasant smells or none at all. The foul odour is not a negative value, it is an issue (i.e., a downside of specific trees growing in specific places). The value that was compromised here is a pleasant olfactory environment.

There is a clear difference for us between managing to resolve issues and managing to satisfy values. Sometimes they are flipsides of the same coin. Cutting down the offensive ginkgo tree resolves an issue AND helps satisfy a value. However, for another example, if one strongly values native biodiversity and the urban forest currently provides a considerable measure of it, there may not be a sensitive issue here but there still may be a strong shift in management emphasis to favour planting trees of native species in nature-like configurations (e.g., not in straight rows ten metres apart!).

According to our observations, most urban forest managers compile their knowledge of public values for city trees from their everyday experiences with members of the public (mostly in the form of complaints), and from the various public participation processes they run in connection with urban forest management planning. Rarely are formal research projects mounted to get a more systematic picture of the public’s urban forest values. Formal research has the advantage that, if done well, the resulting knowledge can be considered quite reliable. On those grounds, and because our research group is keenly dedicated to the cause of sustainable urban forest management, we have undertaken a series of studies across Canada to examine, in a formal way, how urban residents value the trees in the city.

Does increased knowledge change a person’s value set?

We often hear the proposition that people would hold a different value set, or perhaps change the relative importance of their values, if they learned more about all the ways that trees in the city benefit people, and also understood better why the urban forest is managed the way it is. We believe that a considerable amount of this can happen. For example, most people are aware that trees provide welcome shade on sunny, hot days. In our interception surveys, people mentioned shade quite frequently when they were asked what they value about trees in the city. A person delving into the literature about increased skin-cancer risks in children, especially with the kinds of atmospheric conditions we have in cities and considering where climate change is going, might become quite concerned about the degree to which children’s playgrounds are shaded. Knowing this, one might look around one’s own city and notice the dearth of trees (or any other kind of shade provision) in playgrounds. This exposure to new information and the personal reflections it may generate are likely to shift the shade value from one of casual mention to one of supreme importance, perhaps to such a degree that one would argue strenuously for additional tree plantings in and near playgrounds.


Our mission is to enhance and promote the care and benefit of trees for present and future generations in Ontario through education, research and awareness.