INSECTS AND DISEASES 



pass the winter In this condition, hatching In 

 the spring about the time of the beginning of 

 the growth of vegetation. From these winter 

 eggs females are hatched which bear living 

 young, which may also bear living young and 

 so on for several generations until autumn, 

 when eggs are again deposited for the winter 

 stage. 



Fortunately weather conditions together with 

 parasitic and predaceous Insects hold them more 

 or less In check. Because of the difficulty of 

 getting at the underside of the curled leaves 

 where these lice mostly work they are extremely 

 hard to control. Lime and sulphur when the 

 trees are dormant destroy as many of the eggs 

 as It comes In contact with. A tobacco extract 

 Is quite effective as a contact spray In the grow- 

 ing season. The trees must be closely watched 

 and If the lice appear In any considerable num- 

 ber they must be promptly attended to or seri- 

 ous damage Is likely to result. 



These are by no means all the insect pests 

 which the fruit grower has to combat, but they 

 are usually the most Important. Canker worm 

 and tent caterpillars often do great damage 

 in unsprayed orchards, but they are easily 

 controlled by an application of a poison as soon 

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