50 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION 



The state insectary is still continuing its endeavors to introduce 

 parasites which will prey more effectively upon the immature stages 

 of the black scale and it is hoped that every success will attend their 

 efforts so as to reduce the expensive operation of spraying. 



THE IVY OE OLEANDEE SCALE 



Aspidiotus hederae (Vallot) 



Figures 3-6 



In some parts of the San Joaquin and Sacramento valleys, this 

 insect often becomes quite abundant on the leaves, and, in a few 

 instances, on the fruit of the olive trees. In the latter case, it is 



Fig. 5. The ivy or oleander scale, Aspidiotus hederae (Vail.), on an olive leaf. 



(Original.) 



(Photo by Div. Sci. Illust., Univ. Calif.) 



specially annoying to the growers of ripe pickling olives. The in- 

 fested fruits become spotted because the retarded development of the 

 tissues around the scales leaves pits or depressions and the checking 

 of the coloring in these places causes them to remain green while the 

 rest of the fruit assumes the natural dark color (fig. 3). The insect 

 gets its common names from the two plants most universally attacked, 

 although in this state others are as commonly infested. It is what 

 is called a true armored scale; that is, the female has over its small, 

 nearly circular, yellow body a protection in the form of a thin gray 

 or whitish circular scale about one-twelfth of an inch in diameter. 

 The scale of the male is more elongated and somewhat smaller, the 

 mature insect being small and winged as in the case of the black 

 scale. In most cases, the scales are scattered over the surface of 



