Dying Trees - Ask Extension
A lot of trees in our community are dying from some kind of disease that causes green splotches on the trunk & limbs & the bark peels revealin...
Knowledgebase
Dying Trees #542954
Asked February 05, 2019, 10:05 PM EST
A lot of trees in our community are dying from some kind of disease that causes green splotches on the trunk & limbs & the bark peels revealing black coating underneath. I took a picture & would like to know if anyone can tell me what it is, please?
Prince George's County Maryland
Expert Response
We are happy to help.
The green splotches that you are seeing are called Lichens.
They are harmless and are actually a sign of good air quality.
Lichens are an interesting life form (a symbiotic relationship between an algae and a fungus) and simply grow on things that are still or relatively so, like rocks, fences and slow-growing bark.
Here is our page on Lichens: http://extension.umd.edu/hgic/topics/lichens
Pay close attention to the tree leaf canopy in the growing season (tho if that limb's fall would threaten people or property, remove it sooner than later).
This page helps Maryland homeowners decide when it may be time to remove a tree: http://extension.umd.edu/hgic/topics/how-do-you-decide-when-remove-tree
cm
The green splotches that you are seeing are called Lichens.
They are harmless and are actually a sign of good air quality.
Lichens are an interesting life form (a symbiotic relationship between an algae and a fungus) and simply grow on things that are still or relatively so, like rocks, fences and slow-growing bark.
Here is our page on Lichens: http://extension.umd.edu/hgic/topics/lichens
Pay close attention to the tree leaf canopy in the growing season (tho if that limb's fall would threaten people or property, remove it sooner than later).
This page helps Maryland homeowners decide when it may be time to remove a tree: http://extension.umd.edu/hgic/topics/how-do-you-decide-when-remove-tree
cm
What about the peeling bark with black surfaces underneath?
Unfortunately, the black fungus underneath is hypoxylon, a deadly fungus. This is it in its advanced stages. The trees showing the hypoxylon need to be removed.
Here is a good link that explains this fungus: https://www.uaex.edu/publications/pdf/FSA-7557.pdf
While lichen is harmless, when you begin to see a rapid increase and a large volume of it on a tree, it can be an indication that the tree is in decline. It is not the cause of decline, however.
ECN
Here is a good link that explains this fungus: https://www.uaex.edu/publications/pdf/FSA-7557.pdf
While lichen is harmless, when you begin to see a rapid increase and a large volume of it on a tree, it can be an indication that the tree is in decline. It is not the cause of decline, however.
ECN
