Master Gardener: How to prevent brown spots on apples

Q.  We’ve started to harvest apples in our garden, but notice that there are brown areas under the peel on some of the apples.  Do you know why this is happening?
A.  I’ve received similar questions before and I have to admit that I’ve occasionally seen this problem on apples from my Granny Smith apple tree too.  I believe that what we are seeing is a condition commonly called bitter pit.  It is a physiological disorder and develops when an apple tree e