Protect large trees
Large trees can provide critical support for native wildlife communities, as well as shading and visual interest for people. Parks and larger open spaces offer the most opportunity for large trees.
Urban Trees and Forests
Image credits: Gigi Ling, Unsplash
An urban forest is a collection of trees growing within a city. Urban forests can range from remnant native forest patches to trees planted throughout cities in streets, highways, and backyards.
Biodiversity role:
Trees provide vertical structure, nesting resources, cover, and fruit and floral resources. Large native forest patches function as biodiversity hubs, protecting more urban- sensitive species from urban stressors, and even non-native trees can provide structure or food that benefits native wildlife.
Human health role:
Urban forests have several mental and physical health benefits. Some include improved mental health, immune function, and BMI, and lower prevalence of lung cancer and preterm birth. Trees also provide shading and cooling, and high canopy cover can offset the urban heat island effect.
Key tensions and tradeoffs:
Increased tree canopy cover has been associated with increased prevalence of asthma and allergens although results are mixed. It has been linked to gentrification, so strong housing policies should accompany greening. Trees preferred for human benefits may be exotic species that do not provide the same biodiversity benefits as natives.
