88 



PRINCIPLES AND PRACTICE OF PRUNING 



the root area be also reduced by root pruning. In other 

 words, removal of the top upsets the balance between root 

 and top. The result is that the remaining parts make greater 

 vegetative growth than they normally would make and often 

 water sprouts (Fig. 65), and suckers may be developed in 

 greater or lesser number and size. Hence gardeners have 

 formulated the rule that weak-growing shrubs should have 

 their tops pruned severely, but strong ones only lightly. 

 Should severe pruning become necessary to correct the form 



Fir.. 64 ONE OF THE WORST FOES 

 OF TREES IS THE "LINE MAN- 



FIG. 65 TREE'S ATTEMPT TO 

 OFFSET BUTCHERING 



<;r to train a plant, under-stimulation of the top may bo 

 avoided by doing the work piecemeal, say a quarter to n 

 third at a time, with an interval of a week to perhaps several 

 months between, depending upon the character of the plant 

 being pruned herbaceous ones, such as tomatoes grown 

 under glass, requiring very frequent, perhaps even semi- 

 weekly removal of small quantities of foliage, and.trees de- 

 manding not more than one or at most two primings a year. 



84. Injurious effects of pruning on the growth of tree trunks are 

 reported hy German investigators who say the average thickness of 



