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CALIFORNIA CITRUS CULTURE. 



DUSTS. 



A number of valuable insecticides are applied dry, as dusts. They 

 are easy to mix and handle, and are often of great service to the farmer 

 and orchardist, especially in controlling red spiders or mites on citrus 

 trees. 



Flowers of Sulphur. 



For a number of years flowers of sulphur was used alone as a remedy 

 for mites on citrus trees. It was distributed over the trees by hand or 

 with a blower in the early morning when the foliage was damp, thus 

 enabling it to adhere. The warm sunshine oxidizes the sulphur, the 

 liberated sulphur-dioxide being the killing factor. Accordingly, sulphur 

 is of little avail in the cool summer weather of the coast counties or 

 during the winter months anywhere. However, in the warm interior 

 districts this is still a very effective remedy for mites. 



FIG. 45. A power blower for applying dust sprays in 

 orchards. About forty acres can be treated in one day 

 with such a machine. It costs $115.00. 



