STREET AND HIGHWAY PLANTING. 95 



In spite of the fact that much notice of it has been made in recent 

 years, we still find many cases of bad pruning so general rules for all 

 prunings may not come amiss. 



First of all, in large trees, commence pruning at the top of the tree 

 and work downward, in this way saving labor of going back to dislodge 

 any limbs which may have been caught; and, needless to emphasize, 

 perhaps, the pruner should know from preliminary study just what he 

 wants to cut before climbing the tree, as the aspect of the tree is very 

 different in the crown from the aspect in the street. In making the 

 cuts the saw should be held so that the plane of the cut is parallel to 

 the axis of the trunk and reasonably close to the trunk, so that no stub, 

 or even a suggestion of a swelling, will be left when the scar has healed. 



The branches are often cut off with a stub of varying size left in 

 place. This, in time, has formed about it a collar by the succeeding 

 years' growth of new wood. The dead stub, however, gradually decays 

 and breaks off, leaving an opening into the main trunk which offers an 

 easy entrance for fungus growths or insect pests. The illustrations in 

 Plate 4 indicate the progress in this case. 



Again, unless the cut is properly made, the limbs split and tear away 

 parts of the main trunk as they break. To prevent this, the cut should 

 be made with an undercut first, and then an overcut, as shown in 

 Fig. 48. This process may take more time, but it prevents such splitting, 

 as is shown in Fig. 49. For smaller limbs, for which pruning shears are 

 sufficient, this method can not be followed, but the dangers of splitting 

 are not incurred. 



Pruning shears are most often used to limit the growth of a lateral 

 branch. In this case, of course, the process is simple, but care must 

 be taken to make the cut so that a bud can carry on the growth of the 

 branch, as under other circumstances the limb will always show as a 

 stub. It is always well also to make the cut a short distance beyond 

 the bud, because if too close to the bud evaporation will set in and spoil 

 the bud, at least stunting it. 



For all the larger cuts it has been found best to use a dressing of 

 some kind of paint over the wound, and so prevent decay. If the 

 wound is made in a proper fashion, leaving a flat surface parallel to 

 the axis of the trunk or limb, the tissues of the cambium will grow 

 and differentiate the cells of the bark, which eventually cover the entire 

 scar, forming a cambium layer over the entire surface and a barky layer 

 over that. The difference in the appearance of the bark will always 

 show, but the functions of the tissues will be resumed in a normal 

 fashion as though no branch had occurred. And the wood rings will 

 be laid down about it, increasing the diameter of the trunk as though 

 nothing had happened. 



