53 EXPERIMENT STATION BULLETIN. 



SUGGESTIONS 



Dusting may be done when the foliage is either wet or dry. Some 

 growers prefer to dust at night as atmospheric conditions are usually 

 more favorable. Dusting cannot usually be done satisfactorily and 

 economically when there is much wind. 



Dusting material should be applied to the trees from two directions 

 for each application. A satisfactory way is to dust with the wind on 

 two different days when the wind is in different directions. When dust- 

 ing at night the same method is desirable as there is usually a definite 

 air current which causes the dusting material to drift in one direction. 

 Under ordinary conditions it is not necessary to stop at each tree. 



The cost per tree for material is much higher for dusting than for 

 spraying, but the cost of application is less for dusting. Dusting can 

 be done very much more rapidly than spraying and because of this it 

 is possible to cover the orchard quickly at critical times and to make 

 extra applications when desirable. 



Dilute, dusting mixtures are not recommended at this time. More 

 experimental work is necessary before any recommendation can be 

 made. 



Ordinary commercial sulphur is not suitable for dusting purposes. 

 Only special dusting sulphur should be used. . 



Some foliage injury has been caused where spray guns have been 

 used. This can be avoided if proper care is taken. This injury is usual- 

 ly on the lower limbs and where the gun was held close to the tree. 

 Use the driving spray as little as possible, avoid drenching fhe trees 

 and always use the fine spray when covering parts of the tree close to- 

 the operator. 



