HOW TO PKUNE. 237 



to ascend, so as to nourish and enlarge the attenuated 

 part above. 



9. It is frequently indispensable to have timber 

 trees with a clean, straight, and tall trunk, free from 

 knots, and clear of lateral branches to a considerable 

 height ; and in order to attain this in the most per- 

 fect way, the trees should be grown only at such 

 distances apart as sufficiently to check their side 

 branches. This, however, is sometimes impracticable, 

 and cannot be done ; hence pruning is adopted. 



Without attempting to explain all about pruning, 

 or even fully exhausting any one of its departments, 

 we shall endeavour to lay down a few of the leading 

 principles that should guide us in the operation of 

 daily work. 



When an operation is to be performed upon the 

 human body, the general state of the patient's health 

 is first carefully considered. In like manner, when 

 pruning is to be performed, whether upon a single 

 tree, small group, a shelter-belt, an extensive planta- 

 tion, or forest, the state and condition of the subject 

 must be thoughtfully considered and deliberated upon 

 somewhat in this manner : — 



Is the exposure severe, or is it sheltered ? Is the 

 prevailing wind from the north, south, east, or west ? 

 When was, or when must, thinning be done ? Is the 

 soil such as to produce vigorous growth in the trees, or 

 is it the reverse of this ? Are the trees to be pruned 

 intended for shipbuilding or boatbuilding ? or are they 

 intended for general economical and industrial pur- 

 poses ? or are they only • intended for shelter to the 

 estate, ornamental and beautifying purposes? 



