White blotches on trees with sparse foliage

Asked July 10, 2020, 5:54 PM EDT

I have several trees (Maple, Ash, Linden) on my property that have white blotches on them and have thin foliage this year. They appear to be diseased and not doing well. Can you tell what's creating the blotches and if that is cause for sparse foliage? If so, is there something I can do to help them recover? Thank you for any help you can provide.

Scott County Minnesota

3 Responses

The white spots are lichens and don’t hurt the trees.
Root problems are a common cause of trees doing poorly when they are about 15-20 years old. They are not the only problem.
https://www.andovermn.gov/220/Stem-Girdling-Roots

It seems there is more to the issue because we have several trees that have sparse foliage this year and appear stressed. Two of them are 18 years old but another is only 10 years old. It seems too coincidental that they all are struggling in the same year. Could there be something more? Is there someone in Scott county who could take a look at them?

Some counties have Foresters, and they will come out. An arborist can also diagnose a problem.

It is possible to do an exam yourself.