10 



MASS. EXPERIMENT STATION BULLETIN 207. 



With commercial lead arsenate paste the results as shown in Fig. 4 are 

 much the same, though on the whole injury occurs before T and H get 

 quite as high as with the pure paste, particularly at the higher humidities. 

 The clear and cloudy weather Imes are more nearly parallel than in the 

 other case. 



Apple — Safety Lines for Spraying. 

 AB, clear weather; CD, cloudy weather. 



Fig. 3. — Pure acid lead arsenate 



Humiditu. 



A 70 ^ 



Fig. 4. — Commercial acid lead 

 arsenate paste. 



Fig. 5. — Commercial acid lead 

 arsenate powder. 



Fig. 6. — Pure neutral lead arsenate 

 paste. Crosses indicate cloudy 

 weather tests with no injury; 

 circles, clear weather tests with no 

 injury. 



