310 



On pruning Forest Trees. 



cut through the pith and opposite branches of a pine or fir 

 tree, to show the effects of pruning. 



Fig. 50. Section of a tree of which the branches had died, or been cut 



off in the third year progressively. 

 Fig. 51. Section of a stem of sixteen years' growth, showing the remains 



of branches pruned in the tenth and twelfth years. 



52 53 



Fig. 52. Section, showing the effects of irregular pruning at different 



times. 

 Fig. 53. Section of a stem which has never been pruned. 



It may be observed of pine timber in general, that it is less 

 liable to be deteriorated by dead stumps of branches than the 

 timber of deciduous trees ; the resinous quality of the sap 

 prevents decay, and, being concentrated in the closer texture 

 of the knots, renders them even harder than the other parts 

 of the wood. But the sap of oak, ash, elm, and most other 

 forest trees, has no such preservative qualities ; a rotten 

 stump of a branch will often cause the destruction of the finest 

 trunk. It may be added, in conclusion, that cutting close to 

 the bole, provided it be done in time, is the only way to 

 obtain clean-grained timber, as the above figures show. 

 Stopping or cutting off the branches at some distance from 



