432 FUNDAMENTALS OF FRUIT PRODUCTION 



the large wounds, those made in bulk pruning. This is not an important 

 factor in the culture of the bush or vine fruits but it is usually of consider- 

 able importance in the tree fruit plantation. Indeed it is not too much 

 to say that the life of the average orchard tree is reduced by one-third 

 through the work of wound fungi and bacteria. Fine, as opposed to 

 coarse or bulk, pruning is the most practicable way of preventing losses 

 of this sort. 



Carrying the line of reasoning a step further it becomes evident that 

 pruning should be regular and frequent. This is a statement which most 

 growers know to be true from observation and experience, though the 

 reasons may not always be clearly understood. However, the points 

 that have been brought out furnish an explanation of some of the charac- 

 teristic results following irregular pruning. Trees left unpruned for 

 several years usually seem to require the removal of some of the larger 

 branches or limbs. This approaches the bulk type of pruning and stimu- 

 lates new vegetative growth more than it invigorates the older fruiting 

 wood; new vegetative growth of this sort is as likely to increase as to 

 diminish difficulties. 



What has been stated should not be construed as condemnation of 

 occasional heavy pruning, that is, the removal of a considerable amount 

 of growth. Though heavy pruning as commonly done is bulk pruning, 

 it is not necessarily so. It may consist in the removal of a large amount 

 of shoot growth and small branches and instead of giving rise to water- 

 sprouts, it may stimulate the normal vegetative growth and the fruit 

 spur system. The spur pruning to which reference has been made is 

 evidence to this effect. 



Even bulk pruning is not always harmful. There are occasions when 

 a growth of strong vigorous shoots or watersprouts is desired in some part 

 of the tree. Particularly is this true in trees that have suffered from win- 

 ter injury or some other form of dieback. Then too, it should be remem- 

 bered that many species do not bear on fruit spurs or on short growths of 

 any other kind. Their flower buds are formed freely upon their longest 

 and strongest shoots and bulk pruning which leads to this type of vege- 

 tative growth may increase rather than check fruitfulness. 



Root Pruning. — Root pruning has long been a recognized practice 

 among many European fruit growers, particularly those of the British 

 Isles and the adjacent continental countries and for many years it was 

 generally recommended (but rarely done) in the United States. Though 

 its use has not been limited to trees grown as dwarfs it has been employed 

 much less commonly with standards. In this country particularly, as the 

 culture of dwarf fruit trees has become relatively less important, root 

 pruning has all but disappeared from the list of cultural operations. 

 However, a certain amount of root pruning is almost always accomplished 

 in the regular cultivation of standard orchard trees. For this reason, 



