Results of Tree Surgery 



. /;7^::^"jrrrj HI benellcial results of Tree Surgery, as 

 ^"^n'^)' I'i'Ktised by the Davey Tree Expert Com- 

 [^Tfe^li ""^^ shown more completely and fully 



[i^^ ly^dl by the accompanying pictures than could be 

 done by any combination of words. There 

 are many agencies which cause a tree to decay, and 

 many (recs now standing, which, while fair without, are 

 nothing but shells. Improper pruning or trimming has 

 allowed the entrance of the fungus mycelium, and limbs 

 have become hollowed out by it until they are so weak 

 that the slightest wind may tear them off, with the 

 result of causing still more harm to the tree or inflicting 

 damage to objects below it. 



Sometimes this fungus will eat away the heart of the 

 trunk until it is nothing but a shell; and while to all 

 outward appearance the tree is thriving, even though 

 new foliage may appear each spring and the tree seem to 

 be fulfilling all its functions, it is doomed to an early 

 death unless measures be taken to remove the decay, 

 overcome the cause, and remedy the evil already done. 



A little explanation of the structure of a tree will 

 show why it is possible for one in the condition described 

 to live. The trunk and limbs of a tree are composed of 

 layers of cells or channels through which its food and 

 water are carried. The food substances are drawn from 

 the earth by the roots and are carried up to the outer- 

 most twigs and leaves through the woody layers imme- 

 diately behind the bark, each succeeding layer toward the 

 center of the trunk becoming less and less active. 



These food substances, after being carried to the 

 leaves, undergo a mysterious change by drawing from 

 the air the other components necessary to the growth of 

 the tree. In fact, the tree is really built in the leaves, 

 which have the same function as our own digestive 

 organs. If the leaves were not allowed to grow on a tree, 

 it would soon die. The "sap," as the upward moving 

 substance is called, becomes transformed by the chemical 

 action which takes place in the leaves into what might 

 be called the "blood" of the tree; for, as it descends to 



[9] 



Filling such as Ihis Is far wiirst than nono 



