It is possible you may be referring to cherry shot hole, a fungal disease on the cherry tree. You may notice yellow leaves with reddish brown spots. The fungus overwinters on fallen leaves, and good control can be achieved by raking and removing all cherry leaves from the planting area. No chemical control is recommended.
mh

Thank you for the rapid reply. I was suspecting that cherry shot hole fungus might be the culprit (based on my rudimentary internet searches). The tree is very open to air and sun, so I am somewhat surprised that a fungal infection is the problem, but it definitely fits what I see (with pic included here). We will do our best to rake and remove all of the cherry leaves, but I am worried that many leaves have already disintegrated into the soil/grass and it won't be possible to remove them adequately. Is there really no chemical control or other treatment option available? Also, is this fungal disease likely to kill the tree, or if we are especially attentive to raking and removing fallen cherry leaves for the next few years, is it likely that the tree will survive and the disease will be resolved?

Mild, wet spring and early summer weather promotes this leaf spot. Rake up and dispose of infected leaves that fall off the plants. The disease is not serious but causes cosmetic damage. It will not kill the tree. Depending upon the weather next season the disease may not be a problem. Spraying with a fungicide is not practical as the spraying regiment begins when the new leaves emerge and continues every two weeks or so throughout the summer.

mh

 

 

Thank you for this additional information - it is very helpful!