TENDING OF WOODS 81 



always be cut off at any time of the year, and its removal will 

 decidedly benefit the future value of the tree. Pruning of 

 dead branches should be carried out while the trees are 

 young, not later than about twenty to twenty-five years of 

 age. A saw is usually the best instrument to use, and the 

 branch should be cut off as close to the stem as possible ; the 

 cambium then gradually forms a layer of wood and bark over 

 the cut surface, and if the wound is a small one the process, 

 which is called occlusion, is completed in three or four years' 

 time. Dead branches of larch are best knocked off with the 

 back of an axe ; this is an easy operation, and there is less 

 risk of damaging the bark of the stem than when the cutting 

 edge is used. 



The removal of a green branch is a more serious operation, 

 as this reduces the area of foliage ; the wound made is, more- 

 over, a fresh one, and exposes living tissues upon which the 

 spores of fungi may settle, thus introducing rot. As a general 

 rule therefore, it is not advisable to prune green branches 

 unless they are so small that the wound made will be occluded 

 rapidly ; generally no green branch should be pruned if 

 larger than two inches in diameter. The knot made by 

 a green branch is not so bad as one from a dead branch, as 

 the fibres are in connexion with those of the stem, and thus 

 the knot is never a loose one liable to drop out of a board as 

 does that of a dead branch. Oak will stand pruning well, 

 while conifers can also be fairly safely pruned, as turpentine 

 exudes and protects the cut surface. It is, however, very 

 seldom worth while to prune green branches off conifers, on 

 any large scale, as if the woods are so open that pruning is 

 necessary the value of the timber will, in any case, be small, 

 and the amount spent on pruning will probably not be repaid 

 by increased value. 



Large green branches should never be pruned except for a 

 special reason. There is always a flaw at the place operated 

 upon, and the removal of a large branch very seldom improves 



1269 F 



