438 Brooks : The Fruit Spot of apples 



with kerosene-limoid, as recommended by the Delaware Agricul- 

 tural Experiment Station (23), containing 15 percent, of kerosene. 

 The plots consisted of five trees each. The following data were 

 obtained by actual count of the gathered fruit. 



Percentage of picked 

 Fungicide Time of spraying app , es ^^ 



None 



99-7 



Bordeaux May 30 83 



" May 30 and June 8 69 



June 2 and June 8 7 2 



June 2 and June 21 42 



June 21 5° 



86 



K 



a 



<< 



K. L. B. P. May 30 and June 8 



K. L. B. P. May 30 and June 21 39 



These results show that the application made on June 21 was 

 more effective than any other and would suggest that infection 

 usually takes place after that time. 



In the summer of 1907 further tests as to the time of infection 

 were made. The Bordeaux used was of the 3-3-5° formula. 

 As the fungus had been found to make a poor growth in alkaline 

 solutions it was thought advisable to try the effect of lime as a spray. 

 Five gallons of lime were added to each fifty gallons of water for 

 this mixture. A resin-lime-solution was also used. It was pre- 

 pared by adding five pounds of lime and five pounds of resin fisn- 

 oil soap to fifty gallons of water. As it was not known that the 

 fungus was the primary cause of the trouble, it seemed possib c 

 that some compound with little or no fungicidal value, but whic 

 would stick to the fruit as well as the Bordeaux, might have a 

 hardening effect upon the epidermis and thus decrease the spot- 

 ting. Accordingly calcium phosphate was formed as a precipe e 

 by mixing dilute solutions of lime and sodium phosphate, 

 and a half pounds of lime and five pounds of sodium phosphate 

 were added to each fifty gallons of water. The plots consisted 

 five trees each. The following results were obtained by actua 

 count of the spotted and unspotted apples on the trees at the tirn 

 of gathering. 



