96 THF CONNECTICUT POMOLOGICAL SOCIETY 



SAN JOSE SCALE (Aspidiotus pernicious) 



By PROF. H. A. BALLOU 



IT is not the purpose of this brief paper to offer any re- 

 sults of original work on this subject, but rather to 

 bring to your notice a few facts gleaned from various 

 sources, both regarding the insect and some of the reme- 

 dies for controlling it, especially kerosene. 



In this work I have consulted the available literature, 

 most of which came from the Department of Agriculture, 

 Washington, D. C. , and the agricultural experiment sta- 

 tions, and included, among others, the following authors : 

 Dr. L. O. Howard and C. L. Marlatt, Washington, D. C; 

 Prof. W. E. Britton and Dr. W. C. Sturgis, of the Connec- 

 ticut Experiment Station, New Haven ; W. G. Johnson, of 

 Maryland; A. H. Kirkland, Mass., and W. B. Alwood, of 

 Virginia. 



The San Jose scale was for some time supposed to have 

 been introduced into the United States from Chile, but now 

 it is believed that it was transported from the United States 

 to Chile instead ; and, indeed, in the light of all evidence we 

 are not justified in assuming that any other country was more 

 probably the original home of this insect than North America. 



It was first noticed in the San Jose valley of California, 

 about 1870, but was not definitely named till 1880, when 

 Professor Comstock described it and gave it the name of 

 perniciosus, or pernicious scale. 



For several years the Department of Agriculture at 

 Washington conducted experiments on remedial measures 

 to be used against this insect ; and then it was supposed 

 that it was confined by climatic conditions to the Pacific 

 coast. In '93, it made its appearance in Virginia, and this 

 was the first intimation that the east was to be visited by 

 this pest. Before the end of August, '94, it was known to 

 exist in Florida, Maryland, Pennsylvania, New York ; and, 

 during '95, in Massachusetts, Connecticut, Delaware, Ala- 

 bama and Louisiana. Nearly every case of infection in the 

 east can be traced, more or less directl)^, to one or the 

 other of two prominent New Jersey nurseries. 



