Trees help moderate the speed of urban motorists by defining street edges. Trees also provide protection from the elements, shielding pedestrians from wind, rain, and sun. Trees also help reduce pollution, lower ambient air temperatures, and prolong pavements by protecting it from heat damage caused by high temperatures. The effects of trees in an urban setting also have psychological benefits. Trees help reduce blood pressure as researchers have discovered that the presence of trees has a calming effect on people. Kaid Benefield laid out his argument for the urban tree canopy in his piece, “The Case for More Urban Trees”.
Beyond all these benefits, trees add greatly to the aesthetic appeal of a location. John Lavey posted on Community Builders has created a gallery of animated gifs showing neighborhood locations with and without trees to underline this argument.
A few of the photos are below. The removal of trees makes these urban spaces seem stark and less inviting. For more visit: Street trees, and streets without trees (via Wayback Machine).