Hello,

I am sorry to hear about your Yoshino Cherry.   Yoshino Cherry (Prunus x yedoensis) grows in U.S. Hardiness zone 5 through 8. It prefers sun to partial shade and moist well drained soil. When it is mature, it can tolerate drought but should have constantly moist soil.

Yoshino cherry is susceptible to many pests and diseases.  Aphids, scale, spider mites, leaf-eating caterpillars, tent caterpillars and borers are some of the pests that attack the tree.  Disease include leaf spot, twig cankers, mildews, blights and rot. Here is a link to the most common diseases. 

https://www.canr.msu.edu/news/yellowing_leaves_and_leaf_loss_reported_in_tart_cherries

Yellowing of the leaves or chlorosis can be caused by a lack of iron in the soil. This yellowing tends to start at the edge of the leaf to the center. It would appear that your tree has a leaf spot and perhaps chlorosis but it is difficult to make a diagnosis from the picture. You could contact the the MSU Plant and Pest Diagnostic Lab and arrange to send a sample for analysis. Go to:  https://www.canr.msu.edu/pestid/  to learn how to submit pictures and samples. 

 You could also contact a certified arborist to advise you. Go to:  www.treesaregood.org  the website of the International Society of Arboriculture to find an arborist in your area.

Good luck with your cherry.

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