12 



MASS. EXPERIMENT STATION BULLETIN 207. 



Cherry. ■ — The cherry appears to be much less resistant to injury than 

 the apple. Fig. 8 gives the safety lines for clear and cloudy weather with 

 pure acid lead arsenate paste. Comparing this figure with Fig. 3, we 

 see that temperature is a more active agent with the cherry than the apple, 

 and that this is even more marked in cloudy weather, though with less 

 difference at low temperatures and high humidity. 



Cherry — Safety Lines for Spraying. 

 AB, clear weather; CD, cloudy weather. 



Fig. 8. — Pure acid lead arsenate 

 paste. 



Humiditu 



Fig. 9. — Commercial acid lead 

 arsenate paste. 



Fig. 10. — Commercial acid lead 

 arsenate powder. 



Fig. 11. — Pure neutral lead arse- 

 nate paste. Crosses indicate 

 cloudy weather tests with no 

 injury; circles, clear weather tests 

 with no injury. 



