JOURNAL 



OF 



ECONOMIC ENTOMOLOGY 



OFFICIAL ORGAN AMERICAN ASSOCIATION OF ECONOMIC ENTOMOLOGISTS 



Vol. 6 JL^NE, 1913 No. S 



Proceedings of the Twenty-fifth Annual Meeting 



of the American Association of Economic 



Entomologists 



(Continued from page 257) 



PRELIMINARY REPORT ON THE PARASITES OF COCCUS 

 HESPERIDUM IN CALIFORNIA ^ 



By P. H. TiMBERL.VKE, Bureau of Entomology 



In the early days of citrus fruit culture in California the soft scale 

 {Coccus hesperidum Linn.) is said to have been one of the worst of the 

 scale pests, and to have vied with the black scale {Saissetia olece Bern.) 

 in destructiveness and difficulty of control. At the present time it is 

 little feared by intelligent growers, and in fact plays a rather insig- 

 nificant role in the citrus orchards of southern California. Its present 

 harmlessness is due apparently to its inability to withstand the com- 

 bined effect of fumigation and the recurrent attack of parasites. 



Outside of the fumigation districts the soft scale may be frequently 

 found on cultivated and native shrubbery, yet rarely in large colonies, 

 most often existing in a scattered condition and apparently always 

 under these circumstances being heavily parasitized. As the soft 

 scale, like most Coccidse, is essentially gregarious in habits, we are 

 led to believe that, whenever it is found scattered by ones or twos over 

 the foliage of its host plant, this condition is due to, and character- 

 istic of, heavy parasitism. 



Inasmuch as fumigation appears to be quite as fatal to the parasite 

 as to the host, it is not surprising on the other hand, that the soft 

 scale, when it does break out in a citrus orchard, should increase in 

 an alarming manner for a time and form large clustered colonies on 

 the woody shoots. Such outbreaks do occasionally appear and are 



1 Published by permission of Dr. L. O. Howard, Chief, Bureau of Entomologj-. 



