100 DEPARTMENT OF AGRICULTURE. [Pub. Doc. 



In the foregoing observations we find the following motives 

 attributed to the Downy Woodpecker: — 



It is said to make rings of punctures — 



(1) to secure insects from beneath the bark. 



(2) to catch insects that come to seek the sap. 



(3) to prepare hiding places for insects, in which it later seeks them. 



(4) to take sap. 



(5) to take cambium. 



(6) to take the inner bark. 



(7) to sharpen the bill. 

 (S) to exercise, as in play. 



There is sufficient proof found in stomach examinations alone 

 to show that the bird takes cambium. Small pieces of the 

 inner bark often are found in the stomachs of Woodpeckers, 

 taken purposely or accidentally while swallowing their chief 

 food, which consists of destructive insects. Undoubtedly the 

 Woodpeckers hammer much in play, and this serves to wear 

 down the end of the bill, which otherwise because of its rapid 

 and continuous growth would become so elongated as to be 

 useless for its main purpose. 



The reader may judge for himself whether the above evi- 

 dence is sufficient to convict the Downy Woodpecker of making 

 circlets of pits. In any case further evidence is needed re- 

 garding the depth of the holes usually made, the prevalence 

 of the habit, and what nourishment, if any, the bird secures in 

 the operation. There is hardly sufficient testimony to convict 

 the species of injuring the trees. So far as the writer's ob- 

 servation goes, the vigor of the trees seems to be increased 

 by these small rounded holes, whether made by the Downy 

 Woodpecker or Sapsucker, although McAtee has shown that 

 the Sapsucker holes injure the wood of timber trees, causing 

 defects in the lumber. The large rectangular holes made by 

 the Sapsucker sometimes destroy limbs or entire trees by 

 girdling. 



The series of small holes made by Woodpeckers on sound 

 apple trees may have the effect of stimulating growth. Scrap- 

 ing off the outer bark of fruit trees or slitting it vertically 

 often produces a similar effect. 



On the whole, the Downy Woodpecker is one of the most 



