Japanese Maple White Patches on Bark - Ask Extension
Japanese maple has white patches on the bark over most of the branches. Looks like fine powder but doesn't rub off when touched. Tree gets morning sha...
Knowledgebase
Japanese Maple White Patches on Bark #750616
Asked May 18, 2021, 11:32 AM EDT
Japanese maple has white patches on the bark over most of the branches. Looks like fine powder but doesn't rub off when touched. Tree gets morning shade; partial afternoon sun. What are the white patches? Do we need to treat it--with what?
Westminster, MD
Carroll County Maryland
Expert Response
The patches are lichen and are harmless. Lichen are a combination of algae and fungus which live in combination and, because it has its own chlorophyll, can carry on photosynthesis and "feed" itself. They merely use other plants for support. Here's more: https://extension.umd.edu/resource/lichens
No treatment necessary.
Ellen
