EXPERIMENT STATION BULLETINS. 



473 



TABLE 20. — MATERIALS USED IN CHERRY DUSTING AND SPRAYING EXPERIMENTS. 



Material 



1921 



Lime-sulphiir 



Bordeaux* 



Sulphur dust 



Dehydrated copper sulphate dust 



1 J^ gal. in 50 



4—6—50 



90—10 



15 per cent dehy- 

 drated copper sul- 

 phate. 



l^gal. in 50. 



4—7—50. 



80-10—10. 



20 per cent dehy- 

 drated copper sul- 

 phate. 



*Hydrated lime was used and at the rates indicated. 



The rate of dilution for lime-sulphur solution was increased from IM to IJ^ 

 gallons in 50 as the weaker dilution did not give complete control in 1920. 

 Bordeaux mixture was made in 1920 with 6 pounds hydrated lime in 50 but 

 was increased in 1921 to 7 pounds in 50 so as to more surely counteract any 

 tendency to foliage injury. Most of the sulphur dust used in 1920 was of 

 the 90-10 mixture (when poison was used), but in 1921 the 80-10-10 mixture 

 was used. This mixture contains 10 per cent of hydrated lime which insures 

 better distribution. The strength of the copper sulphate dust was increased 

 from 15 per cent in 1920 to 20 per cent in 1921 and further, 10 per cent of talc 

 was added to the mixture so as to improve its physical condition. 



Application. All dust was applied with a large power duster and the 

 duster was usually drawn by a tractor. In 1920 the work was usually per- 

 formed under satisfactory atmospheric conditions while in 1921 conditions 

 were always favorable when the work was done, most of it being done in 

 the evening or early morning. The trees were dusted from two directions 

 at each application. A power sprayer which maintained a pressure of 225 

 to 250 pounds was used for all spraying operations and the material was 

 applied to the trees with a spray gun. 



Applications were made at the periods here indicated : 



ENGLISH MORELLO. 



1920 



1st. Just before blossoms opened 

 2nd. Just after blossoms fell 

 3rd. Two weeks after the second 



application 

 4th. About July 1 

 5th, After harvest 



Dusts and sprays 



u u u 



il u u 



u u u 



1921 

 Dusts and sprays 



U (I u 



u u u 



u u u 



MONTMORENCY. 



1920 



1st. Just after blossoms fell Dusts and sprays 



2nd. Two weeks after first application " " " 



3rd. About July 1 Dusts only 



4th. After harvest " " 



1921 

 Dusts and sprays 



u u a 



Neither 

 Neither 



