Hi Eileen, 

Thank you for your email and pictures. My name is Emily Lavely, and I am the tree fruit educator in West Central MI. With the consistent rains this season and the combination of cool and warm weather, sweet cherries have struggled this year across the state. From what you're describing, I think your sweet cherry tree has bacterial canker (a bacterial disease on leaves) and cherry leaf spot (a fungal disease). Bacterial canker infects sweet cherries during bloom when conditions are wet and cool like we had this spring. That is why the fruit are withered now. Fruit become infected and black spots form on the fruit, and there are round spots on leaves that turn brown/black and then fall out of the leaf causing a "shot hole" look. The best management strategies we have are to apply copper to kill the bacteria in the spring when trees are dormant; however, there are no effective treatments that can be applied during the growing season. If you see a canker developing or oozing (which may be a sign of a canker), that can be pruned out of the tree when conditions are dry for 3-4 days. There is more information about this in the article below.

Managing bacterial canker in sweet cherries: What are the options? - MSU Extension

Sweet cherries usually do not get cherry leaf spot. That is typically a problem primarily in tart cherry, but this year, with the rain and warm weather, I am seeing cherry leaf spot on sweet cherries as well. This is a fungal infection of the leaves. Leaves have purple/black spots on the top of the leaf and if you turn the leaf over, you'll generally see white spots on the back of the leaf behind the purple/black spots. When there are lesions, the leaves then turn yellow and fall off the tree. Your tree still has quite a few leaves. Some of the tart cherry trees I've seen do not have any leaves at this point which can be damaging, so your tree should be ok. The concern we typically have is that if the leaves fall too early, trees cannot photosynthate through the end of the growing season and cannot store energy for the winter and for new growth next spring. Your tree has plenty of leaves to photosynthesize and store energy for next year. There is more information in the article below. 

CherryLeafSpot.pdf (msu.edu)

There is not much more to do this year. It has been a very difficult season for cherries in MI this year. I have not seen disease issues like this in the past few years. Feel free to reach out again if you have more questions. 

Thanks,

Emily