Answer: Make a mental note of what you'd like to prune off and then in late winter you can prune your fruit trees back. Remove obviously dead branches as well as crossing, rubbing or broken branches. Then remove misplaced branches. You should be able to rehabilitate your trees. Some apple trees are still productive at 100 years of age. If your trees are very overgrown it might take 2-3 years to get them back into shape. If you need step by step guidance, here's a publication from Oregon State University that is reasonably straight-forward and easy to follow: http://extension.oregonstate.edu/catalog/html/ec/ec1005/
Best wishes with your trees.
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