Good Morning Timothy, 

Thank you for contacting the U of M Extension Service. 

The past few years of drought has been really hard on trees. DId you water the tree on a regular basis during the past summer's drought? It may take a few years for a tree to react. 

Please click on the following link about tree care: https://extension.umn.edu/find-plants/trees-and-shrubs

I would inspect the tree trunk and bark for signs of rodent damage. Also inspect the leaves. Are they just curling and dying? 

I would consider adding a few inches of  wood mulch, a few inches away from the trunk up to about three feet away. The mulch keeps the soil and roots cool and moist.  We've had lots of rain this spring. Hopefully it will recover. 

Good Luck!