PESTS AND PARASITES 



329 



A HIGH-POWER SPRAYING APPARATUS TREATING A MASSACHUSETTS ROADSIDE WITH 

 AN ARSENICAL WASH TO DESTROY GYPSY AND BROWN-TAIL MOTH CATERPILLARS 



Note the water tower, by means of which the tops of the tallest trees can be reached 

 with the poison spray. The National Government is spending $300,000 a year in snch road- 

 side work in an effort to prevent the rapid spread of the gypsy moth by carriage of cater- 

 pillars dropping from roadside trees on vehicles and automobiles, one of the principal 

 means of spread. 



potato tuber and prevents the culture of 

 this staple. The disease was discovered 

 in Hungary in 1886, and has since spread 

 over portions of Europe and into Eng- 

 land, where it is causing great alarm. It 

 has also established itself in Newfound- 

 land, and it is especially from this source 

 that the danger to the United States 

 comes. There is no known remedy for 



the disease, and its existence in the soil 

 practically puts an end to potato culture. 

 Its introduction into the United States 

 would result in the loss of millions of 

 dollars annually. 



The other disease is the "white-pine 

 blister-rust," which has caused enormous 

 losses in Europe, particularly to nursery 

 stock. This disease has, during the last 



