And I got the technique from Bas Van Ende, but I've never used it on peaches or other stonefruit. I didn't trust the integrity of the wood enough but now I know I could. I do sometimes use spreaders, however. I don't generally use the first large branches for my scaffolds anyway, and remove them for branches of smaller diameter that are naturally more horizontal. This may reduce the size of my first crop but beyond that it's hard to slow down a healthy peach. Oversized branches tend to make weak unions and often break under cropload if left unsupported. My peach trees start life as central leaders and I don't convert them to open center until they've begun seriously cropping. The central leader also supplies a place for spreaders- the easiest way to make branches more horizontal. One other point about brown rot. It's very important to keep the fruit thinned in a way that they never touch. I guess you could even make sure that no leaves are touching the fruit so it dries quickly. Summer pruning will also help keep the fruit dryer if done with that strategy in mind.

"If I remove one branch of the "Y", wouldn't that destroy overall shape of the tree? I thought we need to train the tree to wine glass/ tulip shape?" Bluesky, That's the shape I like best and grow all my peach trees to an "open vase". I was really just brainstorming on how you might prune your peach tree. I've never tried to grow a peach next to a wall and I assumed yours may not be getting enough sun (partly because of the wall and partly because of the lack of vigor in the tree). My idea was to grow your trunk really tall (above the deck fence) before the tree is allowed to branch out, so all the foliage would be above the deck wall in full sun. Now that I understand your tree was planted in late summer, that's probably normal amount of growth and your tree may well be getting enough sun behind the deck wall. In that case, you could train it to a typical low vase/open-center tree and keep both branches of the "Y". You might want to train more of the tree's structure away from the deck fence. It makes for a lop-sided tree, but I've done it for some of my trees planted close to property lines in my backyard. One last thing, if you are going to train the tree to a low open-center, I'd probably pull the two branches of the "Y" down a little bit. Just take a couple clothes hangers, straighten them out and push them in the ground as far as you can (these will be anchors). Then bend the two branches down some (but not so far that they break) and tie the the branches down with some string.

It's shedding leaves now because peaches are not evergreen - even in Arizona!! The discoloration is perfectly normal for this process and the tree should bud out and re-leaf in spring with normal looking foliage. I don't see any "black nodules" on the branches - only the presence of latent buds. Can you provide photos of these nodules so we can see more clearly?

Look up "shot hole disease" on peach trees. Look like you have a bad case of it,