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TWENTY-NINTH FRUIT-GROWERS' CONVENTION. 



tion of our orchardists. Colonies have also been sent to Cape Colony, 

 South Africa, Egypt, Portugal, Mexico, Hawaiian Islands, Society 

 Islands, and Florida. When sending colonies of Veclalia, within the 

 State, we request the applicants to send us, at our expense, a box of 

 scale-infested twigs. In this way we secure food for our colonies in our 

 breeding jars. Besides the Vedalia, we have three other Australian 

 ladybirds that prey upon this scale alone, viz: Novius koebelei, Novius 

 bellus, and "black Vedalia." We have also two internal parasitic flies, 

 Lestophonus iceryse and Ophelosa craivfordi. With such a list of active 

 workers you can readily understand that the "cottony cushion scale" 

 has a hard struggle for existence in California. 



Another foreign pest that has done serious injury to orange and 

 lemon groves is the "yellow scale {Aspidiotus citrinus). The late L. J. 

 Rose, of San Gabriel, purchased a small Japanese orange tree and 

 planted it on his Sunny Slope estate. The existence of scale was over> 

 looked at the time. The scale spread to other orange trees in the 

 vicinity, and soon after the celebrated avenue of four rows of grand 

 old orange trees appeared to be hopelessly ruined. Mr. Rose ordered 

 the trees cut back to the trunks and the latter scrubbed with soap solu- 

 tion, but even such heroic measures failed to check the spread of the 

 pest, for as soon as the trees again sprouted, the leaves were found to be 

 again infested. This was in the early seventies. The effect of this 

 scale was to cause the leaves to turn yellow and drop and thus injure 

 the health and productiveness of the trees. In 1889 I called the atten- 

 tion of the orchardists to the existence of an almost microscopic internal 

 parasitic fly, Aspidiotophagus citrinus, that was reducing this scale at 

 Sierra Madre, and advised that no spraying or fumigation should be 

 done in that neighborhood. Colonies were sent to other infested dis- 

 tricts, and now it is rather a rare scale in the seven southern counties. 

 The Horticultural Commissioners of Los Angeles, San Bernardino, and 

 even Riverside allow the parasite to fight it out, and it is most efficient. 

 This parasite, like the scale, is a native of Japan. 



You all remember the hard-fought battle that was waged against the 

 so-called "San Jose scale" (Aspidiotus perniciosus). Although it has 

 a local name, it is nevertheless of foreign origin, and according to Prof. 

 C. L. Marlatt it is a native of China. The late James Lick, of San 

 Jose, was a great lover of and experimenter with trees and plants 

 from other countries, and it is claimed that this scale was first observed in 

 his orchard. The " San Jose scale " is not plentiful now in California, 

 owing to an internal parasite, Aphelinus f uscipennis, assisted by the 

 "twice-stabbed ladybird" {Chilocorus bivulnerus) and Rhizohius too- 

 woombse. Prof. W. G. Johnson records having bred 1,478 internal para- 

 sites, Aphelinus fuscipennis, in Maryland from a four-inch peach shoot 

 that was seriously infested with "San Jose scale." As each parasite 



