Tree Issues - Scale/Fungus - Ask Extension
What is the fungus or scale growing on my Adams Crabapple Tree. There are two clusters of 15 trees each at the entrance of our road to our house. ...
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Tree Issues - Scale/Fungus #872102
Asked June 07, 2024, 3:19 PM EDT
What is the fungus or scale growing on my Adams Crabapple Tree. There are two clusters of 15 trees each at the entrance of our road to our house. The trees are 20 years old and there is no water program/underground sprinkler system, just mother nature. The trees are also heavily mulched (6"). There also some leaves dying as well on several trees.
Oceana County Michigan
Expert Response
Hello,
The grayish scaly stuff is called lichen. Lichens are not harmful to trees. They are a symbiotic organism made up of a fungus and an alga that only use the tree as somewhere to anchor. They can indicate a tree lacking in vigor, because they do tend to grow more vigorously when there is more sunlight. When trees lose leaves, there is more sunlight on the branches, and the lichens are more noticeable.
Your leaf loss is probably due to apple scab. This will be very prevalent this year due to all of the rain most areas are getting. It is too late this year to treat with anything, but raking and bagging the leaves can help get rid of places where the fungus will survive to re-infect trees next year. Here is an article about apple scab and how to manage it: https://extension.umn.edu/plant-diseases/apple-scab
I hope this is helpful.
Thank you for contacting Ask Extension.
Ruth
The grayish scaly stuff is called lichen. Lichens are not harmful to trees. They are a symbiotic organism made up of a fungus and an alga that only use the tree as somewhere to anchor. They can indicate a tree lacking in vigor, because they do tend to grow more vigorously when there is more sunlight. When trees lose leaves, there is more sunlight on the branches, and the lichens are more noticeable.
Your leaf loss is probably due to apple scab. This will be very prevalent this year due to all of the rain most areas are getting. It is too late this year to treat with anything, but raking and bagging the leaves can help get rid of places where the fungus will survive to re-infect trees next year. Here is an article about apple scab and how to manage it: https://extension.umn.edu/plant-diseases/apple-scab
I hope this is helpful.
Thank you for contacting Ask Extension.
Ruth
