146 SHADE-TREES IN TOWNS AND CITIES 



made. The trees along streets having large gas-mains need 

 especial watching. The soil around the roots should be 

 tested at frequent intervals, and repairs of mains immedi 

 ately ordered if the presence of gas is detected. 



Tests for gas should be made in the spring, as soon as the 

 frost is out of the ground. During the winter the frozen 

 surface causes an accumulation of gas underneath when 

 there is the slightest leak. When gas is discovered at that 

 season of the year and the leak stopped, there is a chance 

 for the affected tree to recover. On the other hand, if the 

 gas is left in the soil it will poison the tree when it resumes 

 active growth. 



OVERHEAD WIRES 



The injury to trees from overhead wires is frequently 

 serious. While cases of wanton destruction of roadside- 

 trees, to make way for telephone, telegraph, electric-light, 

 and trolley-wires, have been numerous in the past, greater 

 vigilance on the part of property-owners and public officials 

 has caused a lessening of the evil. There may still be found, 

 however, hundreds of trees in public highways that have 

 been lopped, butchered, hacked out of their former shapeli 

 ness by ruthless linemen, who regard nothing with greater 

 contempt than a tree. These crippled shapes are painful to 

 look upon, as are all misshapen or mutilated things, and the 

 pity of it is that a little precaution, a trifle clemency, might 

 have left the greater number of them uninjured. 



The laying of wires underground is becoming more com 

 mon. In many cities ordinances have been enacted requir 

 ing public utility companies to put their wires underground 

 at the rate of a number of miles each year, and no new lines 

 are permitted to be constructed above ground. So long, 



