PRUNING— THE METHOD 427 



while the trees are young they should receive relatively more heading back 

 and less thinning out, because they are then being trained. As they 

 grow older they should receive relatively less heading and more thinning, 

 because they will require less and less training for shape and more atten- 

 tion to the proper functioning of their fruit-producing wood. Species like 

 the peach and grape, which, because of their growing habits, continually 

 require considerable training for compactness and shape, should receive 

 correspondingly more heading when mature than certain other species 

 like the apple or walnut that have entirely different growing habits. 



Fine, as Compared with Bulk Pruning. — In pruning practice and in the 

 consideration of pruning problems aside from those dealing with the heal- 

 ing of wounds, pruning is generall}^ regarded as something directly affect- 

 ing the tree as a whole. It is common to speak of pruning this tree heavily 

 and that one lightly, of heading back one and thinning out another, of 

 winter pruning in one instance and summer pruning in another. A certain 

 tree having been neglected for a number of years is said to require a heavy 

 pruning to bring it back to a vigorous productive condition. Such 

 sweeping statements disregard frequent cases in which though possibly 

 certain parts of the tree should be pruned heavily, certain other parts 

 should be pruned lightly, if at all. If a heavily pruned tree fails to attain 

 quickly a vigorous productive condition there is query why the result has 

 not been satisfactory. When it is decided that another tree requires 

 only a light pruning, only a very few branches are removed. If such 

 pruning is attended by some of the results usually accompanying heavy 

 pruning there is speculation regarding the reason. These statements, 

 which will be recognized as based upon very general experience, show that 

 pruning is regarded somewhat as a bulk problem — as something which 

 is decided on for the tree as a whole, done to the tree as a whole and to 

 which the tree as a whole responds. Yet the results frequently obtained 

 indicate nothing more clearly than that pruning is not exactly a problem 

 of bulk. 



Results Following "Dehorning." — The sucker type of growth that 

 almost invariably follows very severe cutting back or "dehorning" is 

 well known. If the dehorning has been done in winter or early spring, 

 numerous comparatively upright shoots are produced during the following 

 summer. The usual practice is to thin these out and head back those 

 that are left, in order to develop as quickly as possible new fruiting 

 branches. Thus is the tree "rejuvenated." So well is this procedure 

 understood that the question as to when and how to rejuvenate trees has 

 been considered practically settled. However, even a cursory examination 

 of a tree that has recently received such a treatment shows that only a 

 part has responded. Undisturbed branches in the lower part of the 

 dehorned tree usually continue to grow in the ordinary way. Their 

 spurs bear flowers and fruit but little more regularly and yield a product 



