206 



PRINCIPLES AND PRACTICE OF PRUNING 



manufacturing organs of the tree (29). It would be. 

 however, only in very extreme cases that summer prun- 

 ing would ever be devitalizing, certainly where one makes 

 the single summer pruning. Such pruning, in some cases, 

 might give increased vigoj. In others very little differ- 

 ence will be noted. In still others, the growth may be 

 modified to the extent that there is less vegetative 

 growth, but even in the last case there is modification 

 rather than devitalization. 



The result of a single summer pruning, as recom- 

 mended for these young trees, is not so much a question 

 of vigor as it is a question of change in direction of 



growth or energy. The 

 clipping-back of a ter- 

 minal forces the growth 

 into desirable, new lat- 

 eral framework rather 

 than into a useless, addi- 

 tional terminnal growth. 

 There are cases where 

 frequent summer prun- 

 ing at short intervals 

 during the summer has a 

 tendency to check or 

 dwarf a tree; for ex- 

 ample, in growing dwarf 

 trees, we must not only 

 have a dwarfing stock, 

 but we must practice 

 frequent pinching back 

 of shoots (Chapter 

 XVI). Again walnut 

 trees may be dwarfed by 

 FIG. 170-pARTiAi. DEHORNING FAILED removal of all lateral 



Old Italian Prune tree partially dehorned growth for a period of 

 four years ago. Note that the treatment ap- ,-p, , 



parently had little influence upon fhe vieor of VCarS. 1 HCSC last tWO 



the small fruiting branches and indivHual ~ QCPC hnwpvpr urp PY- 



fruit spurs of the limb not cut back. CaSCS, HOWCVCr, ar< 



