226 



PRUNING 



in the summer as that given to similar trees in the winter 

 have generally produced less new growth and slightly smaller 

 trunks and root systems and have not borne any earlier or 

 larger crops. As a matter of fact, in most of the experiments 

 recorded, the yields from the summer-pruned trees have been 

 less. 



Certain types of summer pruning may occasionally be 

 desirable. The pinching out of undesirable shoots just after 

 growth starts in newly planted trees may be of advantage in 

 forming a proper framework in young trees. Water sprouts 

 or suckers in old trees may well be rubbed off in early spring. 

 Young trees which appear to be quite dense usually ^'open 

 up" well when their first crops are borne. It may be de- 

 sirable to head back an occasional limb on a young tree during 

 the summer simply to maintain a better-shaped tree. 



2. Determining How Heavily the Trees Should Be Pruned. 

 Although the general principles underlying pruning hold for 

 trees of all ages, old bearing trees generally require heavier 

 pruning than young non-bearing trees. Accordingly, it is 

 well to consider separately the pruning of yoimg and of old 

 trees. 



Procedure: 



(a) Prune young non-bearing trees lightly. 

 (6) Prune young bearing trees lightly, 

 (c) Prune old bearing trees more heavily. 



(a) Prune Young Non-Bearing Trees Lightly. The best 

 results are usually secured by pruning young trees lightly. 

 Experiments in this and other countries have shown that with 

 young trees pruning is a dwarfing process. Such trees pruned 

 heavily each year have smaller trunks and smaller main 

 branches, make less total top and root growth, have fewer 

 fruit spurs, come into bearing later, and bear smaller crops, 

 at least for the first few years, than trees pruned lightly. 

 This is illustrated by Table 36 from Michigan Extension 

 Bulletin 148. 



