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Lichens on Trees: Harmless Indicators of Stress, Not Killers

Morgantown, WV: light green mushroom/barnacle growth on trees. Front yard tree dead, others sick. What is it? Can save?

ID: Lichens

Symbiotic fungi + algae. Not parasitic—just anchor on bark. Indicate stress (age, drought, etc.) but don't cause it. Good air quality indicator.

Action

No control needed
Fertilize trees you want to keep
Water during drought
Something else killed the dead tree

Lichens are everywhere—just more visible on stressed trees.

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