SHADE TREES AND THE LAW 
247 
public service corporations must not be allowed to damage 
trees through the stringing of wires, the laying of pipes or 
in any other way. 
Some states have tried to curb incompetent tree 
workers by a system of licenses based on examination. 
This would be a help where there is not a thorough system 
of tree supervision as there is in Massachusetts and would 
be a help to private individuals wishing to have work done 
on their own grounds. 
When appropriations are insufficient to meet reason¬ 
able demands the issuing of permits to responsible and 
competent firms or adjoining property owners for planting 
or pruning puts the work on a wrong basis, but is better 
than no control. 
