Answer: Based on your description and the time of year, I suspect your tree is suffering from cedar apple rust, a fungal infection. Some varieties are more susceptible to infection than others, but if rust is a common problem in your area you may need to follow a routine preventive spray program to keep your tree healthy -- for cedar apple rust it need to be started very early in the season while the tree is still in the bud stage and then repeated. Please contact your county extension to obtain a definite diagnosis and based on knowing that, determine how to proceed. They will have the most up to date recommendations on what to use and how/when to apply it for best results.
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