ELECTRICAL INJURIES TO TREES. 



17 



rights run a risk of lowering the value of the property. Most of the 

 very high-tension transmission services, however, are at present on 

 private property and seldom interfere with trees. High-tension lines 

 are affected seriously merely by close proximity to trees; therefore 

 these rights of way have to include broad strips of land, which of course 

 is expensive. 



On general principles it is not wise to allow wires to be attached 

 to trees, although this is often done. Trolley and electric light wires 

 are frequently guyed to trees, but they are a source of danger, since 

 injury is likely to occur from the crossing of the wires, and lightning 

 discharges occasionally pass from the wires to the tree, causing damage. 



FIG. 14. — Showing different types of guards for electric wires : 1, 

 porcelain dowel guard; 2, porcelain wood guard; 3, wooden 

 sleeve. 



It is, however, often better to allow this than to endure the erection 

 of ugly poles; but proper insulation of the wires should be insisted on, 

 although ordinary insulators have little effect on lightning discharges. 

 The lagbolt system in common use for guying wires to trees is not the 

 best method, for sooner or later the wire and bolt become imbedded 

 in the tree and cause injur3\ Moreover, a direct metal connection with 

 a tree is objectionable, as it has in more than one instance proved. The 

 block system is better, although it may not in all eases be free from 

 objections. In no ease should a Avire be allowed to pass tightly around 

 a tree, as it will girdle it in time. When live wires come into contact 

 with limbs, some type of insulator should be employed similar to that 

 shown in 1, Fig. 14, of which there are various types, some being quite 

 effective in preventing injury from low-voltage lines. The type shown 



