My peach tree is 4-5 years old. Had some good peaches last year and none this year. New leaves grow at the end of the branches and the leaves behind the new ones develop brown holes and die and fall off. The cycle has continued this way all summer. Help
Peach Tree Disease
Certified GKH Gardening Expert
This sounds like "shot hole disease". In this fungal infection, leaves develop brown spots that fall out and leave holes, as you describe. Fruit production is also inhibited.
These articles describe control options for this disease. Some fungicides are not available in all states, so check with a local university extension agent or at your garden supply store for what you can use.