CHAPTER XXIII 

 PRUNING— THE METHOD 



It seems strange that a horticultural practice as old as pruning should 

 have come down to the present with so little realization that it includes 

 questions of kind as well as of amount and of season. Nevertheless, most 

 of the literature is silent on this matter, as though all pruning were 

 necessarily the same in kind, except perhaps for the innumerable detailed 

 ways of cutting to certain buds or of leaving certain spurs or shoots for 

 replacement purposes. The fundamental differences between essen- 

 tially distinct practices have not been generally recognized. Instead, 

 attention has been focused upon the minute and less important details 

 of procedure. Without doubt this lack of realization that pruning may 

 vary greatly in kind and that entirely different results attend distinct 

 kinds or types of pruning has been responsible for much of the confusion 

 and apparent contradiction that is evident on comparison of the reports 

 of various writers and investigators. 



Heading Back and Thinning Out. — A number of classifications of 

 pruning as to kind are possible. However, none is more serviceable than 

 one which recognizes the difference between heading back and thin- 

 ning out. It is difficult, if not impossible, to differentiate absolutely 

 between the two for sometimes the removal of a branch or part of a 

 branch is at the same time a thinning out and a heading back. In 

 general, however, the differences between the two are clear and evident 

 even to a casual observer. Thinning out removes entirely a shoot, spur, 

 cane, branch, limb, or whatever the part may be; heading back removes 

 only a portion, leaving another portion from which new growths can 

 develop. 



Influence on New Shoot and New Spur Formation. — Theoretically a 

 heading back that is equal in severity to a certain thinning out removes 

 approximately the same amount of wood and the same number of buds. 

 In practice however, there is a considerable difference. A thinning out 

 that removes 50 per cent of the shoots, gets rid of just half the amount 

 of wood of the past season and just half of the total number of buds, 

 both lateral and terminal. On the other hand a 50 per cent heading 

 back removes somewhat less than half the weight of woody tissue formed 

 the past season and somewhat more than half the total number of new 

 buds, for it removes an equal number of the lateral buds and all the 

 terminals. A heading back that is equal in severity to a certain thinning 



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