Abstract
Codling moth populations on natural apple fruit trees scattered throughout Nova Scotia are compared with those in commercial orchards. In natural fruit, failure of crop, crop size, degree of isolation, amount of crowding by native trees, and natural enemies determine the level of codling moth numbers. Young commercial orchards require artificial control measures within a few years of first bearing fruit to prevent severe crop losses. In older commercial orchards natural controls require an occasional assist by chemical treatment to contain the codling moth below economically tolerable levels. Such treatment is applied to interfere as little as possible with known natural controls.