Yes it is a tart or pie cherry tree. Mine are just now getting ripe here in so. ill. I just finished picking the last of my sweet cherries(except for the dwarf yellow cherry tree) this evening. They were very good this yr. I would suggest you start picking them before the birds get started. They can clean a tree in a couple of days

"kept spraying it every other night" Really?

"subgenus" may be more appropriate (or maybe not, taxonomists have put both sweet and sour cherries into the subgenus Cerasus). All these different cherry species are very closely related, if one wants to consider them different species. This is one example where the line separating different species is not a clear one. It could even be possible to consider the different cherry families as subspecies. After all, if they can freely interbreed and hybridize with each other, can they not be considered members within the same species? (by this definition we could divide all cherries into only 2 groups: those with 16 chromosomes and those with 32) Or one could attempt to divide cherries into different families: Sweet cherries (P. avium), sour cherries, Black cherries plus Capulin native to the American continent (put into same group), and Asian flowering cherries. Perhaps better classification could be provided if taxonomists utilized multiple degrees of species relatedness/separation, because it is ambiguous whether some of the different cherries should be classified as entirely separate species or subspecies within a singular species, neither of which would be wholly accurate.

They appear to resemble a type of scale but I am not familiar with a species that remains that flat or attaches to the plant in that manner. But there are scores of different species so not inclined to rule that out. I would suggest you take a sample of a branch or stem with these creatures attached into your county extension office for an accurate ID. They will also be able to tell you how to treat and when. If it is scale, timing is key!!