Answer: Scale insects generally attack the stems and branches, so I wonder if your tree is in the first stages of brown rot or shot hole. Both are fungal diseases common to peaches and nectarines. It's easier to prevent the disease than to control it. Preventative sprays for trees with a history of fungal diseases usually begins in late winter and continues through early spring. I'd suggest taking a sample of the problem to your local Cooperative Extension office (916-741-7515) for a positive identification of the problem. If it's a fungal disease, you can pick up a spray schedule pamphlet.
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