Funny calistoga. I read the whole thing and still thought wynswrld98 meant each fruit was small. The first things I think of when the yield goes way down from one year to the next is lack of pollinators or unfavorable weather at the wrong time. I don't remember hearing of cherries being every other year like apples and some other fruit. For those apparently allowing a tree to overproduce by not thinning can result in biennial crops. They also do less cropping if given a lot of nitrogen so that they produce a lot of vegetative growth at the expense of fruit buds. In that case fertilization when not needed can be the problem rather than the solution.

Unless the parent tree was own root the sucker yours came from is the sweet cherry rootstock and not the named cultivar that was presumably grafted onto it. Either the rootstock seedling happens to be a yellow cherry as well or the whole parent tree, including the roots was the yellow cultivar. Sweet cherry is actually a weed species in this region and suckers to form groves on local wooded hillsides, where it even overtakes and overtops the native red alder trees often present in quantity on the same sites. It also crosses with the much less exuberant, native bitter cherry to produce a nearly fruitless, intermediate hybrid called Puget cherry. Some ~tall examples of the latter are conspicuous when in bloom, on undeveloped land between I-5 and Lakeside School (near Seattle). It is usual to have problems with suckering and bony surface roots with plantings of sweet cherries - perhaps all the more so when these are present as rootstocks for Japanese flowering cherries. All you can do is uncover the bases of the suckers and saw them away. If there are horizontal runners that lead back to the original planting follow these back to the parent tree and saw them off at their points of origin, pull the rest up. You don't, of course want to saw off normal roots of the parent tree - just the ones that are suckering runners like aspen trees and running species of bamboos produce. This post was edited by bboy on Sat, Mar 15, 14 at 17:05

"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.

Neither website addresses whether the fruit is edible.......most would understand that eating diseased fruit is probably not a recommended activity and that dried, mummified fruit are not at all appealing anyway. Why would you even want to eat them??? To me, the far more pressing issue was communicating that this is a disease, not some aberrant type of fruit that has suddenly appeared, and the website(s) does in fact address how to treat or control.