Of Plantations. 495 



On Pruning. 



Great attention and sound judgment are required in the 

 management of mixed plantations. For, on the one hand, if 

 left too thick, the trees are injured, and the underwood de- 

 stroyed ; while on the other hand, if left too thin, the stems 

 of the selected trees do not rise to proper heights, and na- 

 ture does not perform the pruning operation on their stems, 

 so that recourse must then be had to artificial means, for 

 checking and removing over-luxuriant side branches, a cir- 

 cumstance by no means desirable, as natural pruning is much 

 preferable to artificial means. 



When proper attention is paid to thinning well-arranged 

 mixed plantations, but little artificial pruning is required in 

 training timber trees. Because the proximity of the branches 

 of other trees, preventing the light and air, and other nourish- 

 ment, from freely reaching the strong side branches of the 

 selected trees, those are in consequence checked in their 

 growth, they soon become overtopped by the crown 

 branches of the trees of which they form members, dwindle 

 away, and are ultimately pinched off, by the gradual increase 

 of the stem timber. Hence the term u natural pruning." 



The remarks on pruning which follow, apply generally 

 to oaks and all other hard-wood forest trees, and in a limit- 

 ed degree only to the fir tribe. 



When large branches are cut off close from the stems of 

 healthy thriving trees, the bark and young wood soon 

 grow over the wounds, so that the stems of the trees appear 

 quite perfect. But that is deception, for no adhesion or 

 union takes place between the young wood and the stumps 

 of amputated large branches. Sap wood unites with other 

 sap wood, but never with heart wood. By the union of 

 the bark and sap wood over the stumps of the branches, 

 they are close covered, or as it has been called, " sealed 

 " up," and the sap which flows annually in the trees, con- 

 densing round the stumps of the branches, promotes decay 

 and rot, which soon communicates to the whole tree. The 

 disease is fatal, and the only remedy is to fell the mangled 

 trees, and replant. 



Unfortunately, the king of the forest, " the oak," is more 

 susceptible of injury from injudicious close pruning, and has 

 been more generally practised upon in that way, than most 

 other valuable timber trees. The injury, and ultimate loss, 

 will therefore be national, as well as individual. Old oak 

 trees which have done growing, are but little, if in any de- 



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