INSECTS INJURIOUS TO ORCHARD TREES 449 



bodies of mothers that have laid their eggs early in the 

 summer. A small chalcid-fly is a very common parasite of 

 this scale and often controls it effectively when it once becomes 

 well established in an orchard. The parasites cannot be 

 depended on for absolute control, however, and spraying is 

 usually necessary. The sulphur-lime spray gives very good 

 results, but some prefer a kerosene emulsion, one part to four 

 parts of water, or a 5 per cent, or 6 per cent, distillate oil 

 emulsion. The spraying should be done in the winter in order 

 that the over-wintering young may be killed. 



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