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PRUNING AND THINNING. 



PT. IV. 



If the dying boughs are cut off, the sap, which 

 would have been uselessly expended in them, invi- 

 gorates the present shoots, or bursts forth in the form 

 of new shoots, and, in returning, contributes to the 

 growth and nourishment of the roots. In such cases, 

 trees are often killed by being left ' to see where they 

 break out.' They should be cut immediately : ' Bis 

 dat qui cito dat.' This waste of the sap in the stem 

 and branches, without the power to return to the root, 

 is the reason why trees which are barked round just 

 above the earth in general die. If young trees are cut 

 down just above the earth, they shoot out again freely 

 and continue to grow ; but if they are only barked, 

 the sap going up the heart-wood diminishes the chance 

 of an outbreak below, and without this outbreak the 

 roots must die froni a want of descending sap. 



If a branch is not cut at the foot of a living twig, 

 its end should be again cut off at the foot of the new 

 shoot, in order that the descending sap of the new 

 shoot may deposit wood and bark over the cut end. If 

 long stump ends are allowed to remain, they rot before 

 the new growth in diameter of their stock has inclosed 

 and covered them. 



Near natural ponds, where the whole soil holds, the 

 presence of trees is beneficial, from their prevention of 

 evaporation, and from the condensation which takes 

 place in moist warm weather, particularly on smooth- 

 barked trees ; but near artificial ponds or dams no 



