I have a link to a description of peach leaf curl, a fungus that causes the leaves on the peach to discolor and curl. I would urge you to take samples to your local Penn State Extension and have them sent off to Penn State's plant clinic. You will get a diagnosis and a treatment plan. Once a disease has entered a tree, the tree is in stress trying to fight off the infection. It is not uncommon for the tree to drop its fruit in order to martial its energies against the pathogen.Here is a link to your local Penn State Extension website.

My peach trees have brown rot. They have not dropped their fruit, their fruit is shriveled up still hanging from the tree. I know that I need to remove these shriveled peaches and all the branches that are speckled with the brown rot. My question is when? Do I just leave it alone till winter or do I remove all infected parts and treat it with a fungicide immed? My trees are bad with most smaller branches showing the fungus. Also as peaches only grow on year old branches does this mean I will not have any peaches again next year as I'll be cutting off all the new growth?  Please let me know. Thank you. 

I'm glad you identified the pathogen. As long as the fungus is present and active, it is spreading spores and thus spreading infection. Here is a recommendation by Purdue extension

Perhaps I'm not posing my question correctly. As most of my smaller new branches show signs of the fungus, I'm assuming they need to be remover. When should I be cutting all of these branches off? Now cause they are infected? Or winter when I traditionally prune? Will my tree survive that kind of massive pruning in midsummer?if all of t of the new growth is being cut off, will I hav peaches next year?  Finally, should I be treating it with a fungicide to control the active infection? Please let me know. Thank you. 

As a Master Gardener, I can't speak to this with the authority of a licensed arborist or trained plant pathologist. What I can tell you is that whatever diseased tree parts can be removed should be removed as soon as possible since they are creating more infection. Fungicides are designed to be preventative. You need to begin spraying in the early spring before the infection appears, and continue on a regular basis throughout the season. Fungicides are meant to suppress the formation of the fruiting bodies, not cure the disease.

I don't know if your tree will survive or not. It is under extreme stress since the fungus is inside as well as outside the tree. Here are three ideas.
1. The pathology is already taken over the tree, and you need to cut out all the parts that show signs of the fungus, bag or burn them, and remove all evidence of the disease. Each time a new fruiting body appears, it has to be removed. You need to scout the area for any plant debris, and be vigilant for the season.
2. You can consult a licensed arborist. The International Society of Arboriculture has a way to find one nearby through a zip code search. Here is a link to their website.
3, You can consult with your local Penn State Extension. The horticulture outreach educator is a fruit tree expert, and may be able to help you.
Here is her contact information.

• Horticulture Educator

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