Street trees are vital to a neighborhood’s health. They fulfill a variety of critical functions that often go unrecognized.
Benefits of street trees include:
- Carbon sequestration: The larger the tree, the better it is at fighting climate change. Sweetgum (Liquidambar styraciflua) and London Planes (Platanus × acerifolia) are considered among the best performers when it comes to carbon storage. The London Plane in particular is “one of the most effective tree species in removing pollution in urban areas.”(1)
- Shade and cooling: Trees with dense foliage provide much-needed shade for pedestrians and residents, and cooling to nearby buildings. A Berkeley tree canopy study found “that city trees saved $12.58 per tree in annual electricity costs”. (2)
- Mental health: Studies have shown that trees have a calming effect; they reduce the levels of the stress hormone cortisol in humans. A greener neighborhood provides more mental health benefits to its residents. (3)
- Habitat and wildlife benefits: Street trees provide nesting sites for many species of birds – including Oakland’s official city bird, the Black-Crowned Night Heron – as well as food for pollinators and other wildlife. Trees also provide safe passage and canopy crossings that bridge dangerous sidewalks and roads.
- Reducing runoff: According to the previously mentioned Berkeley tree canopy study, the average street tree also intercepts 1,478 gallons of stormwater runoff.
- Offsetting air pollution: Air pollution causes more than 9,000 deaths each year in California alone (4), and nearly 6 million Californians suffer from respiratory illness (5). City trees filter significant amounts of particulate matter from the air, “up to 11,100 tons per year.” (6)
And we’re not even talking about edible trees, like lemon or olive trees, or trees with medicinal benefits, like ginkgo! Our neighborhood has lots of those too! More on that in another blog post.