174 



THREE COMMON SCALE INSECTS/ 



H, T. FERNALD^ PH.D._, STATE NURSERY INSPECTOR, AMHERST, MASS. 



Fruit growers often find scale insects (formerly called 

 bark lice) on their trees, and of these there are three kinds 



which are abundant 

 in Massachusetts. 

 These are known as 

 the San Jose scale, 

 the oyster-shell scale 

 and the scurfy 

 scale. 



The San. Jose 

 Scale. 



This pest, which 

 is the most destruc- 

 tive scale we have, 

 is now generally dis- 

 tributed in the 

 State. 



The scale is 

 round (circular) in 

 outline, or nearly 

 so, and when full 

 grown is about as 



Different stages of the San Jos6 scale, enlarged five times. 

 (From Virginia State Crop Pe.st Commission Bulletin, 

 1904.) 



large as a small pin head, highest in the middle and grayish- 

 brown in color. The young are born alive, beginning about 

 the middle of June, and are produced at intervals of two or 

 three days for about a month before the parent dies. The 

 young are very small, yellow, and crawl about for a time 

 till they find a satisfactory place on which to settle. During 

 this time they may crawl on to the feet of some larger insect 



« Nature Leaflet No. 33, March 31, 1911. 



