This is a revised and updated edition of the book Tree Fruit Production, first published in 1959 and extensively revised in the second edition in 1972. Considerable advances have been made in recent years in the scientific production and handling of deciduous tree fruits in North America. This third edition brings together in up-to-date usable text book form the essence of pertinent research and practical experience on the subject. Although the principles involved in the different operations of orchard management, such as pruning, soil management, fruit thin ning, and harvesting remain constant, practices and techniques have been undergoing considerable change. Economic and social changes have been brought to bear in altering the approach to such aspects of pomology as tree size, plant density, mechanical harvesting, pest control and irrigation. Greatly increased costs of production have swung the emphasis of attention toward the wider use of organic chemicals in the orchard. Growth regulating substances are finding a place in the orchard, not only for fruit thinning, preharvest drop control and weed suppression, but also for other purposes such as promotion of early flowering, tree train ing, pruning and the advancement and extension of the harvest season. The trend toward the smaller, more easily and economically managed apple tree which began slowly some three or more decades ago and increased rapidly in subsequent years is now complete.