Is Evidence-Based Conservation Applied in Urban Forestry? A Case Study from Toronto, Canada

Adam R. Martin, W. Eric Davies, Danijela Puric-Mladenovic, Sandy M. Smith

Faculty of Forestry, University of Toronto, Earth Sciences Building, Toronto, Canada.
Faculty of Forestry, University of Toronto, Earth Sciences Building, Toronto, Canada; Information Management and Spatial Analysis, Southern Science and Information Section, Ministry of Natural Resources, Peterborough, Canada.

DOI: 10.4236/ojf.2014.41005                

Abstract

Evidence-based conservation seeks to incorporate sound scientific information into environmental decision making. The application of this concept in urban forest management has tremendous potential, but to date has been little applied, largely because existing scientific studies emphasize the importance of urban forests in large-scale ecological and anthropogenic processes, but in practice, scientific evidence is ostensibly incorporated into North American urban forest management only when deciding the fate of individual trees. Even under these disjunctive conditions, the degree to which evidence influences tree-level decisions remains debatable. In analyzing preliminary data from a case study from Toronto, Canada, we sought to test if and how scientific evidence factored into the decision to remove or preserve 53 trees, located in close proximity to a provincially significant area of natural and scientific interest (ANSI). We found that by far the strongest tree-level correlate of the recommendation to remove or preserve trees was whether or not an individual tree was in conflict with proposed development. In comparison, species identity, tree condition, and suitability for conservation were statistically unrelated to the final recommendation. Our findings provide the basis to expand our analysis to multiple case studies across Canada, and internationally. Furthermore, when interpreted with available research and policy, our preliminary (and future) analysis highlights clear opportunities where scientific evidence can and should be readily incorporated into urban forestry management and policy.

Keywords

ANSI; Arboriculture; Black Oak; Evidence-Based Conservation; Land Use Planning; Toronto; Tree Bylaw; Urban Forestry; Urban Forest Policy

Conflicts of Interest

The authors declare no conflicts of interest.

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