Moss can be removed from trees and bushes by hand, through power washing or through the application of chemicals, such as copper sulfate or lime sulfur. Chemical control methods are not typically recommended for homeowners because the chemicals used are toxic and corrosive.
Most people choose to remove moss by pulling it off by hand. The process is labor intensive, and it is best performed during the winter when the plant is dormant in an effort to minimize damage. During the winter months, homeowners can also remove moss with a power washer; this method is not suitable for delicate plants and is most effective on large tree trunks.
Professionals sometimes use copper sulfate to remove moss from trees and shrubs. This chemical is available in dust and liquid forms and is applied while the tree is dormant. It works by disrupting photosynthesis, and it must be reapplied every few years unless measures are taken to increase sunlight and air circulation to the mossy area.
Copper sulfate is highly toxic to wildlife and should not be used near bodies of water. Lime sulfur is another chemical that is sometimes used to control moss. Like copper sulfate, it must be reapplied every few years. It is corrosive to wood surfaces and harmful to insects, including honeybees.