CHAPTER XXVII 

 The Relations of Birds to Fruit Orchards 



IN a large part of North America the apple is the lead- 

 ing orchard fruit. The pear and the peach are much less 

 generally grown, although each is important in certain 

 localities. The same is true of cherries, plums, and quinces, 

 though in the aggregate each of these fruits is of great 

 value. 



These orchard trees are subject to attack by a great variety 

 of insect enemies. Root, trunk, branch, twig, leaf, and 

 fruit each part has special enemies that too often blight 

 the crop. Fortunately, however, most of these enemies are 

 largely held in check by various birds that frequent the 

 orchards and help to keep a balance that is favorable to 

 fruit production. Where birds are scarce the task of fruit- 

 raising is greatly increased. 



TRUNK, ROOTS, AND BRANCHES 



The trunk and the larger roots and branches of most 

 fruit trees are subject to attack by a great variety of burrow- 

 ing insects. In general, the eggs are laid on or in the bark 

 by a winged beetle or moth. These eggs hatch into larvae 

 that burrow in bark, sapwood, or heartwood, remaining at 

 work until full grown as larvae. They then change to pupae, 

 generally in or near the outer bark, and emerge later as 

 adult beetles or moths. 



Common examples of such destructive insects are found 

 in the round-headed apple-tree borer, the flat-headed borer, 



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