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BOAKD OF AGRICULTURE. [Pub. Doc. 



d--- 



The cut, Fig. 3, gives a view of the outer surface of a 

 section of bark taken from a small oak. From this small 

 piece of bark the bird proljably secured at least six of the 

 larwT that were found in its stomach. The holes, a, b, c, d, 

 e, f, indicate those from which the larvae 

 were taken. 



Fig. 4 gives a view of the inner sur- 

 face of the same piece of bark, showing 

 how true was the stroke of the bird, for 

 its beak, piercing from the outside, went 

 directly to the centre of the burrow 

 where the insect lay entirely hidden 

 from view. The letters a, b, c, d, e,f 

 indicate the holes, showing size and 

 shape, where the 

 bird's beak came 

 through to the 

 inner surface . 

 f Seventeen larvae 

 of bark beetles 

 and 12 ants were 

 found in the bird's 

 stomach. 

 During the win- 

 no. 3 (reduced two-thirds).- tcr the chickadccs 



Oak bark pierced by dowuy ^^^^ ■ l)erform 



woodpecker. ^ j ./ i 



priceless service 

 by destroying quantities of the eggs 

 of such insects as those of the tent 

 caterpillar and canker worm moths. 

 The owls and some of the hawks are 

 useful, not alone in the sununer, when 

 they destroy many of the May beetles, 

 larger caterpillars and moths, and keep 

 down the increase of the mice and 

 squirrels, but those that stay through 

 the winter are also useful then by 

 keeping squirrels, mice and hares in 

 check. Plares and mice sometimes do great damage by 

 gnawing the bark or roots of trees. All of these animals 



Fio. 4- — Inner surface of the 

 same bark, showing the clian- 

 nels of i)ark lieetles and the 

 woodpecker's perforations. 



