APPLE GROWING 



ease, the point of attack, the time of making 

 It, and when and with what It can be most 

 easily destroyed. The number of Insects and 

 diseases which affect the apple is so great that 

 It is simply out of the question to treat them 

 all In detail here. We have therefore selected 

 nine Insects and three diseases as those pests 

 of the apple which are most common and whose 

 effects are usually most serious. The essential 

 facts In their life histories and their vulnerable 

 points will now be pointed out. The method of 

 study may be taken as applicable to any other 

 pests which it may be necessary to combat. 



Insect Pests. — Of the many insects which 

 affect either the tree or the fruit of the apple, 

 the nine selected probably Inflict the most dam- 

 age and are the most difficult to control of all 

 those in the Northeastern States. According to 

 their method of attack all insects may be di- 

 vided into two classes : biting and sucking. 

 Biting insects are those which actually eat parts 

 of the tree, as the leaves or fruit. These are 

 combated by the use of stomach poisons as we 

 shall see in the following chapter. Sucking In- 

 sects are those which do not eat the tree or fruit 

 directly, but by means of a tubelike proboscis 

 suck the juices or sap from the limbs, leaves or 



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