How to Manage Pests
Pests in Gardens and Landscapes
Air pollution damage is caused by mostly invisible gases, especially ozone and sulfur oxides. Typical
air pollution damage includes browning on the underside or margins of leaves or other discoloring, and
dead and prematurely dropping leaves or needles. Symptoms may develop soon after short-term exposure to
high concentrations of air pollutants or after longer exposure to relatively lower pollution levels. Azalea,
birch, fuchsia, pine, and sycamore are especially susceptible to injury.
Provide proper cultural care and control other causes of stress to keep plants vigorous
and increase their tolerance to pollution. Grow more plants because plants help in several ways to reduce
air pollution. Particulates become trapped by foliage and are washed by precipitation from foliage to
the soil. Gaseous air pollutants are absorbed by bark and taken into plants through leaf stomata. Plant
tolerant species in areas where air quality is especially poor.
patches on leaves caused by ozone
Tip burn and banding on pine needles