Question
Hello.  I have property in the Catskills of mixed connifers and hardwoods.  It was
late June when I noticed the leaves on many of the maple trees looked like they
had a case of measles on the underside of the leaves.  Do you know what this
might be?  Is it serious and will I be able to protect the trees? Thanks, Linda

Answer
Sounds like leaf spots either from a disease or possibly an insect gall wasp. Neither one will kill the tree. They may cause the tree to drop their leaves sooner than normal but will have no effect on the overall health of the tree. These can be controlled but the controls would have to be started as the leaves bud out. The population of the both leaf spot disease and gall wasps vary greatly from year to year and next year may not even be present. I would not worry about these.