Answer: A variety of things can cause spots on apples. Apple bitter pit shows as pale brown spots on the skin or the interior. This usually appears in fall or when the apple is in storage. Apples usually taste somewhat bitter. It is caused by a lack of calcium.
Another possibility is the codling moth caterpillar, which starts feeding at the core of the apple and tunnels out. It leaves behind what could be described as an internal brown streak. Damage is usually seen in midsummer to early fall.
Without seeing the fruit, it's hard to make a diagnosis. I suggest you contact your County Cooperative Extension office for help. They are at 905 E. Forest Ave., Mora, 679-6340.
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