Removal of Lichen and Moss from Coral Bark Maple

Asked April 6, 2017, 1:11 PM EDT

I have several Coral Bark Maples in my yard and each of them has varying degrees of moss or lichen in them. I have read that spraying the trees with Copper Sulfate will kill the moss and lichen and not harm the plant. Please confirm to me if this is one of the methods of dealing with the moss or suggest another method. If copper sulfate is the chemical that I should use, I have found it very difficult to locate in garden shops. Can you recommend a location in the Beaverton/Hillsboro/Newberg/Sherwood area that sells it? Thanks in advance for your help. Tyler Bowman

Washington County Oregon lichen on trees horticulture

1 Response

Moss is a normal resident in the pacific northwest due, in part, to our clean air. Neither moss nor lichen damages trees or shrubs but both are common on slowly growing woody plants. Copper is a component of various commercially prepared products which are designed to remove moss and lichen from living plants.These products are available at many retail sources, among them garden centers, hardware stores, big box stores, and some groceries and drug stores.

The following information is excerpted from “Controlling Mosses” (http://bryophytes.science.oregonstate.edu/page18.htm):

“Moss control is generally achieved by physical removal, chemical treatment, or a combination of these methods. These methods have different costs, effectiveness, and potential side effects that need to be considered. A key point is that mosses flourish under certain environmental conditions. If you try to control mosses, but do not address the underlying conditions that favor moss growth, they will surely return (see “Basic Biology of Mosses” http://bryophytes.science.oregonstate.edu/page2.htm).

“Be cautious if you decide to attempt chemical control. Many methods of chemical control can cause plant or animal injury, stains, corrosion, or pollution of soil and water. For these reasons, chemicals should be applied according to the label instructions.”