208 THE SPRAYING CAMPAIGN 



sprayed in the ordinary way. In this connection it ought to be 

 said that too great care can not be exercised to prevent animals 

 from getting at the poison. This does not often happen and yet 

 it occurs often enough to make extreme caution desirable. In 

 particular, the empty kegs ought to be destroyed after the 

 poison has been used. Cases are known where such kegs have 

 been left about the orchard and have caught rain water and 

 animals drinking this water have been killed. All poisons should 

 be kept under lock and key and should be taken out only as they 

 are wanted for use. It is a very easy thing to become careless 

 about this where men are using such materials constantly. 



The question of the effect of sprayed fruit on human beings 

 was also investigated by the Michigan Experiment Station. 

 Grapes sprayed with Bordeaux mixture were chosen and it was 

 found that even though all the spray materials used were to 

 remain on. the fruit a person might eat 300 to 500 pounds at 

 one meal without getting enough copper sulf ate to be dangerous. 

 In testing the matter of arsenic, apples sprayed with Paris 

 green were examined, and it- was shown that a person might 

 eat eight or ten barrels at one time without being in danger from 

 the arsenic. .These figures seem fairly reassuring, even for a 

 person with a robust appetite, and we may therefore conclude 

 that it is safe enough to eat sprayed fruits. Nevertheless, it is 

 poor practice to have anything on the fruit which, can be seen at 

 the time it is marketed. If it becomes necessary, therefore, to 

 spray late in the season use a material that does not show. 



The spraying program is sure to vary somewhat in different 

 seasons and in different localities ; yet it is possible to map out 

 a fairly constant program for each of the different fruits, and 

 it may be of interest and value to suggest such a general scheme 

 here. 



For apples and pears the usual sprayings would be as follows : 



First spraying in the autumn after the leaves have fallen, 

 using one of the miscible oils about 1 gallon of oil to 12 gallons 

 of water or using lime-sulfur at the winter strength, say 1 to 

 9 or 10. This spraying is principally for the San Jose scale and 



