I'm not sure if what you have is what we have on our peaches, but ours get some fungus that makes brown rotten spots on them. Glenn has been spraying them with neem oil at blossom drop and a couple more times as they ripen and the problem is much diminished. For the tiny part, if they are tiny because the tree puts too many on, the only solution is to thin, thin, thin. Year before last we pulled off 6 four gallon bucket fuls of small fruit. This year there won't be peaches because that freeze a week and half ago got them.

The same thing happened to our young Elberta peach tree, Mulberryknob. The blooms the frost didn't kill were mostly blown away by a wind storm. We still have approx a dozen peaches on the tree...for now. ;)

(The Bing cherry bloomed for the first time, too, but the same thing happened to it. I think we'll get two cherries out of it, this year. The Granny Smith also bloomed for the first time, but...the frost and wind seem to done for most or all of them, as well.)

How's about a pic of our tiny little peaches? We're kind proud of them, you know. They're about the size of the end of your thumb. We're kinda hopin' they'll get a little bigger than that before they're finished. ;)

I always thin peaches to a spacing of at least 6" apart on the tree, usually when the fruit are dime-sized or smaller. That gives me peaches of a decent size. If you want even bigger fruit, thin them to 8-10" apart. In a great year, I remove hundreds of tiny fruit per tree. I don't do it all at once. I usually do it in at least 2 cycles about a week apart. Why? So if a late freeze or a wind storm is going to remove a lot of the fruit for me, there's that point after the first thinning when there's still too many fruit on the tree. If weather comes along and takes a bunch of them, maybe there still will be some left for us. This year the weather got them all.

There's several diseases that could be causing the black spots, including brown rot and bacterial spot. I'll link the OSU Peach Home Orchard Fact Sheet that includes the conventional recommended spray schedule. In order to stop the diseases in their tracks, you have to spray at certain points in the bloom cycle of the plant. They have photos of each point so you know what it looks like.

We don't follow the conventional spray schedule and, like Dorothy and Glenn, if we spray anything at all, we use neem oil. Most years, when we actually have fruit on the tree after the last freezing/frosty weather, we are so dry that we don't have fungal diseases develop here. Y'all have a lot more moisture and higher humidity up there, so you may have higher levels of disease pressure. I think I have had peach leaf curl once and brown rot once in all the time we've been here, but then, we often don't have fruit survive the freezing weather long enough to develop disease.

My dad never thinned his fruit (a throwback, I think, to growing up with too little food in the Dust Bowl and Great Depression days) and always had little peaches. I always thin mine because I like big peaches.

Warren, If your fruit have made it this far, they may survive. Well, except for all that hail in the forecast. I have never seen hail in the forecast as often as it is here in Oklahoma. I don't remember ever losing a peach crop here to hail, but we've had strong winds (excess of 55 mph and blowing dust---you know the type of wind storm I'm talking about---where it looks like all of Arizona, New Mexico and West Texas are blowing into OK) blow the very young fruit right off the trees. Some wind storms take all the fruit and others have only thinned it out really well for me.

Dawn

Here is a link that might be useful: OSU Fact Sheet