Written by Melanie Lenart, University of Arizona
Urban trees play multiple roles when it comes to local air pollution. While trees in general help reduce air pollution, including absorbing the greenhouse gas carbon dioxide, some species contribute to local smog by emitting volatile organic carbons (VOCs). Planting locations of individual trees and species selection make a difference in the overall pollution balance.
Many urban trees help clear the air of pollution, although some are better at it than others (Table …