12 A Bulletin on Orchard Practice 



during the dormant season are from about a thirty-second to 

 nearly one-eighth of an inch in diameter. They are of a 

 grayish color, nearly circular in shape, and almost flat, with 

 a pointed, slightly raised center of lighter color. They devour 

 the vital forces of a tree to such an extent that it ceases to 

 be profitable, and will finally die if left untreated. 



Beginning with the first warm weather in May the scales 

 commence to multiply and so continue to increase through the 

 season. The young are born alive and become immediately 

 active in their destructive work of sucking the juices from 

 the plant. 



It is not a difficult matter to control and even to eradicate 

 this pest from an orchard, by use of the sulphur-lime spray 

 properly prepared and thoroughly applied. 



The writer of this article has used the sulphur-lime spray 

 in June with excellent success by applying the standard 

 formula made up to one-half strength. F. A. H. 



OYSTER-SHELL SCALE. 



The Oyster-Shell Scale, so common west of the Cascade 

 mountains, has a different life history from that of the San 



OYSTBB-SHEL.II SCALES enlarged about three diameters. 



