EFFECTS OF PRUNING 145 



after the tree is planted. In some trees pruning will be 

 necessary for a longer time. 



Cause for Pruning. — Under natural conditions of growth 

 many plants grow very thickly and produce so many 

 branches that they crowd each other. The older the plant 

 gets the more the limbs crowd, until the plant reaches a 

 point that the branches become so numerous that much 

 light and air are shut out. In addition to this trouble the plant 

 has so many surplus branches that the root system is not 

 sufficient to continue the growth of so much wood, and at 

 the same time produce fruit. When priming is practised, 

 these surplus branches are removed which allow the food 

 material to go into the production of fruit and flowers instead 

 of wood. 



The pruning of a tree or bush also aids in forming a uniform 

 and symmetrical plant. All of the irregular branches are 

 removed and the others shortened, so that the plant will be 

 uniform. 



The thinning out of the branches aids in controlling insects 

 and diseases. Spraying is made much easier and larger crops 

 are produced. 



The systematic pruning of plants, especially when grown 

 under artificial conditions, aids in withstanding wind storms, 

 and trees are not blown over as easily as when large, long 

 branches are allowed to remain. 



Effects of Pruning. — The regular methods employed in the 

 pruning of a tree or shrub has a tendency to increase growth. 

 Weak plants can oftentimes be made to grow more rapidly 

 by severely pruning the top during the resting period. When 

 such plants are severely pruned all the strength of the roots 

 is used to grow a single upright, vigorous stalk. This acceler- 

 ation of growth is also seen in the rejuvenation of an old tree. 

 This is particularly true of the peach. By cutting oft' prac- 

 tically all of the old top of the tree, you cause the roots to 

 send out many vigorous shoots which in a short time makes 

 another head of all new wood. Occasionally other old trees 

 are treated in this manner, as the apple, elm and sometimes 

 the soft maple. 



Pruning of certain plants also has a beneficial effect on the 

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