All my peaches are small. Is this because the graft died?

Yes this is because the graft died. Most peach trees are grafted and if the graft dies, the roots send up new growth. This is not the same tree that was above the graft before. The rootstock is chosen for its vigor not for tasty fruit. Retired UT Extension Agent Mike Dennison says the only thing to do is take the tree out and start over.
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