Gall on Peach Tree
We took a leaf that has growths on it to the nursery to identify what was on some of our peach tree leaves and what we should do about it. They identified it as gall, but could not match the leaf with pictures they found of other peach leaves. They suggested we send a picture of the leaf to you to get your suggestions. We treated the tree with a bonide oil in early April. It now has peaches that are between a nickel and a quarter coin in diameter. Thanks in advance for any suggestions you may have. We have a peach tree that we bought at a nursery last spring. I don't know its age. it is about 8 feet tall. Only the leaves appear to be affected. Very few of the total number of leaves have the gall. Attached are two pictures of one of the leaves. I forgot to place a ruler beside it, but the leaf is about 3 inches long and 1 inch at its widest part.
This looks like peach leaf curl, a fungal disease on the peach tree. This is a fungal disease that causes defoliation and fruit loss when the weather during bud swell and opening is cool and wet. No fungicides will control the disease after the buds open. It is too late to control now. Next spring you will have to apply a fungicide such as liquid lime sulfur (organic) before buds begin to swell. Thorough coverage of all bark and bud surfaces is important.
See our publication for more information http://extension.umd.edu/sites/default/files/_images/programs/hgic/Publications/HG77_IPM_Series_Ston...