Answer: Fruit trees should be pruned in the winter when they are dormant. It's normal for apple trees to sucker. The best approach is to pull the suckers, or to cut them down as soon as they emerge. There is a product called Sucker Stopper that might help but it's difficult to find. If you find it, cut the suckers down and apply the product to the stubs. It should stop the suckering.
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