CONTROLLING INSECTS 



203 



plant-lice, scale insects, and true bugs, like the chinch-bug 

 and squash-bug. 



There are two ways of applying poisons : one in the form 

 of a fine spray of water, and the other as a dust of dry powder. 

 For trees and 

 bushes and for 

 large areas the 

 spray is always 

 used. We cannot 

 mention all the 

 various spra^ys 

 used, but the fol- 

 lowing are a few 

 of the common 

 ones: 



1. Paris Green 

 is one of the most 

 widely used poi- 

 sons. It is used 



at the rate of one pound to 150 to 200 gallons of water, or 

 for small quantities about a half-teaspoonful to a gallon of 

 water. It should be thoroughly stirred before using. It is 

 well to add a little lime, as lime keeps the Paris green from 

 burning the leaves when the sun is hot. Paris green will kill 

 all insects that chew the foliage. 



2. London Purple is used exactly as Paris green. It gener- 

 ally sticks to the foliage longer than Paris green. 



3. White Hellebore is usually dusted on to kill insects. 

 When used as a spray an ounce to three gallons of water is 

 about right. White hellebore is used mainly for currant- 

 worms on currant and gooseberry bushes. 



37«- 



RESULTS OF SPRAYING 



The crop of one tree. The large pile is good fruit 

 the small pile poor. 



By courtesy of the Ohio Experiment Station 



