DISEASES OF PLANTS SPRAYING 257 



of lead to fifty gallons of water. This will accomplish the 

 two purposes at the same time. 



The third spring spraying is made just after the petals 

 fall from the blossoms. Its chief purpose is to control the 

 codling-moth. It also aids in preventing the trouble from 

 apple scab. As there are two purposes, use the combined 

 sprays as in the second spring spraying. Study Figs. 150 A, 

 B, C, D together. 



For the control of codling-moth on fall and winter varie- 

 ties of apples, a midsummer spraying is advisable. For this 



Fia. 151. Summer spraying by school students. (Agricultural Education.) 



use two pounds of arsenate of lead to fifty gallons of water. 



Principles of Spraying. Always select, if possible, a 

 bright clear day without much wind for all kinds of spraying. 



Do the work carefully and thoroughly. Let all parts of 

 the plants be touched with the spray materials. 



Use special nozzles which throw the materials into fine 

 mists. Learn of the latest and best nozzles and spraying 

 apparatus by writing to the Agricultural Experiment Station 

 of the State. Always consider what are the special purposes 

 of the particular spraying, and use the proper materials for 

 those purposes. 



