of $e (goc&es 



other birds have to feed upon borers and beetles 

 is during the brief time they occupy in emerging 

 from the tree that they have killed, in their 

 flight to some live tree, and during their brief 

 exposure while boring into it. 



Beetles live and move in swarms, and, accord- 

 ing to their numbers, concentrate their attack 

 upon a single tree or upon many trees. Most 

 beetles are one of a dozen species of Dendroc- 

 tonus, which means "tree-killer." Left in un- 

 disturbed possession of a tree, many mother 

 beetles may have half a million descendants 

 in a single season. Fortunately for the forest, 

 Dr. Woodpecker, during his ceaseless round 

 of inspection and service, generally discovers 

 infested trees. If one woodpecker is not equal 

 to the situation, many are concentrated at this 

 insect-breeding place; and here they remain 

 until the last dweller in darkness is reached and 

 devoured. Thus most beetle outbreaks are pre- 

 vented. Now and then all the conditions are 

 favorable for the beetles, or the woodpecker 

 may be persecuted and lose some of his family; 

 so that, despite his utmost efforts, he fails to 



196 



