PRINCIPLES AND PRACTICE OF PRUNING. ' 91 



extending as far each way from the foot of the stem as the 

 height of the tree. A careful examination will discover the 



FIG. i2i. Forms of Pruning-Knives. 



whole surface of the subsoil occupied with the small fibres of 

 full-grown nursery-trees (Fig. 122). It is obviously impossible, 

 therefore, in digging up to avoid cutting and leaving most of 



FlG. 122. Nursery Rows Roots extending under the whole surface. 



the roots behind ; and the tree when reset is unable to sustain 

 or feed for a time its leaves and branches. A part must there- 

 fore be cut off to restore the balance, corresponding in some 



