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. 121. — 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 



Pig. 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 



