Apples are very prone to damage by worms unless they are sprayed throughout the season, but some growers avoid spraying by tying a small paper bag over each apple. We have found that nylon “footies” (used by shoe stores when barefoot customers are trying on shoes) are just as effective as paper bags, but much easier to apply.
We are getting 100 percent protection from apple maggots and 98 percent against coddling moths. (We do not have plum curculio, another apple pest, but I would welcome reports from growers in the eastern U.S. regarding how footies prevent curculio damage.)
Apply the footie within 40 days of petal fall, by sliding the footie over your little finger and bunching the nylon so that at least half the length of the footie slides up the fruit. Make sure the top of the nylon covers the stem. It is not necessary to tie the footie to the branch.