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Name: Jonquil
Status: other
Age: 30s
Location: N/A
Country: N/A
Date: 2/13/2004

I have a yellow lichen on the bark of my walnut trees and want to know if it is killing my tree?It seems to be spreading all over the branches and trunk?

Lichens growning on the surface of bark do not harm trees. Lichens are unique partenerships of an algae and a fungus. They grow on many different surfaces, including bare rock. This web site is an introduction:

J. Elliott

No, lichens rarely are agents of death of trees. Most likely, there are other problems contributing to the decline of your trees. The following should be helpful:

Anthony Brach Ph.D.

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