134 TREES AS GOOD CITIZENS 



ounce per tree may be used. Nitrate of soda is a strong 

 plant stimulant so needs to be used in small quantities at 

 any one time but can be used more frequently. A year's 

 supply of the other ingredients may be applied at one time, 

 using 4 to 12 ounces of the mixture per tree. For heavier 

 soil the same ingredients are used but in different propor- 

 tions, the formula calling for two parts of nitrate of soda, 

 three parts of acid phosphate, one part muriate of potash 

 and two parts of bone meal. The quantity to be used for 

 each tree is the same as in the case of the lighter soil. 

 This fertilizer should be evenly distributed and mixed 

 into the soil in a thorough manner. Too liberal use of 

 the chemical mixture will injure the roots. 



Protection from injury is essential to the young tree 

 on the city thoroughfare. All of us have seen boys swing- 

 ing on the slender stems as if the trees had been planted 

 as a part of a public gymnasium. We have seen trees 

 bent down till their tops touched the ground, by those 

 who find pleasure in watching the flexible stem fly back 

 to an upright position. We have seen trees die as a result 

 of these and similar abuses, because of the loosening of the 

 roots just at the time when it is most important that they 

 should be allowed to gain firm foothold. We have seen 

 men tie horses to the slender trees and have found the 

 horses nibbling at the bark, to the serious injury of the tree. 

 The horses are not to blame, of course, but this is no 

 comfort to the man whose tree is ruined in the process. 



It was to prevent injuries from these and similar 

 causes that the tree guard was invented. The loss of 

 bark caused by horse bites frequently causes a wound 

 which affects the tree's whole future. With the growth of 

 the trunk the old wound accumulates thick edges, invites 

 decay and permits the entry of borers and the growth 

 of fungus diseases. The death of the tree is apt to follow, 



