Exploring the Urban Forest: Evidence of Tree Condition Change across Toronto’s Environmental Gradient

Increasing urbanization creates environmental impacts on flora, fauna, and human populations. Urban trees provide mitigating services that may be maximized by understanding environmental stressors that impact tree health. I explored the relationship between tree condition and urban landcover as evidence of urban stressors. Tree morphology, canopy condition, and insect abundance were expected to vary across an urban land cover gradient, at different spatial scales, and between native/exotic species. These responses were explored in Tilia americana, Tilia cordata, Acer platanoides and Acer saccharnium in Toronto, Ontario, Canada. Specific spatial scales and environmental variables better explained changes in tree response variables. My results suggest Tilia species were more tolerant of urban conditions. Differences between species were described by genera suggesting species trait similarity may determine environmental suitability. Maximizing service provision requires interspecific stress expression consideration. Further research will explore soil conditions, socio-economic factors, and environmental remote sensing in urban tree condition modelling.M.Sc