IO4 THE AMERICAN APPLE ORCHARD 



are already drying and to some extent falling from the 

 trees. The buds for next year have already been rip- 

 ened. Even if large quantities of leaves are eaten 

 from the trees at this time of year, therefore, the prac- 

 tical damage is very much less than it would be if a 

 similar defoliation should occur in early spring. 



Tree Borers There are several different species of 

 borers which attack the apple tree trunks and branches. 

 Only two of them, however, are of any great economic 

 importance, namely, the flat-headed and the round- 

 headed borers. The distinctions between these two 

 species are not of great practical consequence. In many 

 young orchards these insects do enormous damage, 

 sometimes killing a large percentage of the planting 

 between the ages of two and ten years especially. 



The presence of borers in the apple trees can nearly 

 always be detected by the chips thrown out by the 

 working larvae. These will usually be found about the 

 base of the trunk. 



Borers are especially likely to injure trees standing 

 in grass or weeds. Clean culture is therefore a pre- 

 ventive, to a considerable degree, of this sort of dam- 

 age. Application of lime, ashes, lye washes and other 

 caustic materials have some effect in driving away the 

 borer or killing the eggs, but cannot be relied on as 

 preventives. 



The most effective treatment of trees once infested, 

 and indeed the only effective treatment, is to dig out 

 the larvae by hand. These worms eat into the wood 

 and under the bark of the trunks and can be reached 

 and killed if one takes the necessary labor. A man 

 can cut out a majority of them by using a sharp knife. 

 Although some damage will result to the tree by this 

 sort of cutting, it will always be less than will result 



