PREFACE 



FEW practices in the handling of plants, especially of 

 fruit trees and bushes, attract so much interest as 

 those of pruning. The methods are so varied, the 

 results so diverse and the apparently contradictory 

 opinions of growers so tenaciously held that this subject 

 is always one of the surest to arouse discussion and hold 

 attention at horticultural society meetings and wherever 

 demonstrations are given by agricultural colleges and 

 schools and by farm bureaus. 



During the past two decades the principles of plant 

 physiology have been more satisfactorily applied to plant 

 production and crop management than ever before in the 

 history of agriculture. Especially during the latter half 

 of this period have experiment station and other workers 

 been devoting annually increasing attention and time to 

 pruning investigations in their efforts to discover new 

 truths and to prove not only disputed and undecided 

 points, but to test many beliefs and rules of thumb which 

 have been accepted as true, but which increasing knowl- 

 edge of plant physiology has led these investigators to 

 challenge. Much has been discovered, much verified and 

 much disproved. But the reports of these investigations 

 are necessarily so scattered that very few fruit growers 

 have access to them, and students of agricultural col- 

 leges and schools, even if they know how to search, lack 

 the time to hunt through the libraries of their respective 

 institutions to find this literature. Many bulletins and 

 reports are out of print, so none can be had. Hence the 

 demand for a book which shall present the really im- 

 portant features of these investigations as well as set 



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