Authors: Greg King*, University of Alberta, Carson Hvenegaard, University of Alberta, Sarah Quann, Tree Canada, Eric North, University of Minnesota
Topics: Urban Geography, Urban and Regional Planning, Environmental Science
Keywords: Urban forest, urban trees, dendrochronology, radial growth, densification, climate extremes
Session Type: Virtual Paper
Start / End Time: 8:00 AM / 9:15 AM
Room: Virtual 33
Presentation File: No File Uploaded
Over 80% of Canadians currently reside in urban areas, with more than two thirds in lower density suburbs. However, lower density development can negatively impact land supply, transportation, infrastructure, and environmental conservation. In response, urban planning policies increasingly promote densification as a more sustainable urban form. A challenge is that densification pathways such as infill housing often result in the loss or negative impacts on existing urban forest, especially in mature neighbourhoods with old, large trees that significantly contribute to urban greenspace services.
We use dendrochronology, the science of tree-ring analysis, to investigate the impact of past residential development on the growth and resilience of urban trees. In 2019, samples were collected from 57 mature white pine (Pinus strobus) trees located in the Arlington Woods neighbourhood and adjacent undeveloped greenspace of Ottawa, ON. Following standard techniques we cross-dated and measured annual ring widths. Absolute dates reveal all trees were present prior to residential development in the late 1960s. We compare absolute growth, associated climatic drivers, as well as the response, recovery, and resilience of these trees to extreme events before and after development. We also make comparisons between residential trees and trees remaining in a naturally forested greenspace.
Using data from mature urban trees retained during residential development, we provide insight into how development affects their growth, climate response, and resilience. The results of this research will contribute toward strategies aimed at retaining mature trees and their associated benefits in the face of increased urban densification.