Spraying 



should be done with the lead arsenate within three 

 weeks of the fall of the petals so as to catch the 

 caterpillar before it enters the fruit. 



For sucking insects sprays containing nicotine are 

 the most effective. They kill through the skin, and 

 young caterpillars and even the raspberry beetle may 

 also be killed by it. Where both aphis or PsyUa 

 and caterpillars are attacking fruit trees in spring 

 this is therefore the best spray to use, and it is most 

 effective if appHed just before flowering in the case 

 of apples, just after with pears, cherries, and plums. 

 The attacks of Capsid bugs upon apples are only to 

 be dealt with effectively by means of a nicotine 

 wash appKed when the active green bugs are piercing 

 the young fruits in May, the results of their work 

 being conspicuous in autumn in the shape of rough 

 warts on the surface. The same should be used 

 where bugs are attacking flower buds, etc. 



Paraffin emulsion and quassia and soft soap are 

 also useful sprays against aphides, and recently a 

 very efficient spray containing saponin instead of 

 soft soap has been devised. All of these kill by 

 suffocating the insects hit. They do not poison the 

 food, and it is useless to use them unless the insects 

 are present and in a position to be wetted thoroughly 

 with the spray. 



VIII. Suffocation by Dipping. — ^Where plants in 

 pots attacked by aphis or scale have to be dealt with, 

 and especially where they are attacked by mites, as in 



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