Ask Mr. Smarty Plants

We always first try to establish what tree we are talking about, what variety or species. Of the genus Acer, maple, there are 23 native to North America and 12 native to Pennsylvania. So, we settled on Acer pensylvanicum (striped maple) to use as an example, since this USDA Plant Profile map shows that it grows in the vicinity of Allegheny County, USDA Plant Hardiness Zones 5b to 6a. 

In answer to your question, nope, we never heard of such a thing as the top of a maple turning red and then turning back green again. Is that all you wanted or did you want to know what caused it? We haven't a clue but we'll poke around in the Internet and see if anyone else ever heard of it. 

We found a couple of forums, and we don't ordinarily put much stock in the q&a's on them because they are usually just gardeners sharing thoughts. However, several mentioned drought stress as causing this phenomena in maples. If you have had less rain than you are accustomed to, we would suggest you stick a hose deep down in the soil around the roots, turn it on at a slow dribble, and let it run until water reaches the soil surface. Repeat this two or three times a month or until the rainfall seems sufficient. One other person said it sounded like a grafting failure on the maple tree, and the tree would now revert to whatever the parent root was. We know very little about grafting, and if that is what happened, there is not a thing in the world you can do about it. 

Now, the next time someone asks us if we ever heard of a maple tree turning red in June, we can say "sure."