104 



ers go after the borers. Spores are produced in enormous num- 

 bers right around those tunnels. It is inevitable that the wood- 

 peckers will get the spores on their bills and on their ieet and on 

 other parts of their bodies. Those birds, when they go away, 

 will carry those spores Avitli them and leave them where they 

 alight the next time. If they happen to fall in a wound of some 

 kind and the conditions are favorable, the infection is going to 

 occur. That is the kind of evidence. It is inferential. As for 

 actually knowing that infections have resulted in that way, we 

 have no evidence. Of course, it is exceedingly difficult, if not 

 impossible, to get it. .Vs to tiic; migi-ation of the woodpeckers, 

 I have it on (lie authority of a competent oriiitliologist tliat some 

 kinds of them (h) travel long distances. 



DR. FISHER : There are certain forms of woodpeckers Avhich 

 go south in winter, but those are not the birds which are highly 

 specialized which secure their food from the trees. They are 

 birds which seek their food like the flicker, which feeds largely 

 on nuts, and the redheaded woodpecker, which feeds quite ex- 

 tensively on grasshoppers and other insects, as well as fruits; 

 but our Avoodpeckers, our native, resident woodpeckers, are 

 rarely migrators. As to the injury to the trees, the nut gath- 

 erers, it seems to me, produce very many more wounds than the 

 woodpeckers produce. They either jar the smaller trees with 

 stones that break the bark and form places for the insertion of 

 the germs, or they use climbers which injure the bark, and enter 

 the wood very much further than the woodpecker's bill does. 



MR. DETWILER: I have the report of a field agent who has 

 been investigating the relation of birds to the carrying of dis- 

 ease. This investigation has been in progress only about a 

 month, and the data is of an elementary character. However, 

 there are two paragraphs Avhicli have a bearing on this subject. 

 First, the field agent says : 



"I can truthfully state that every blighted tree I have seen 

 since I have begun this study, has had its l)ark punctured by 

 woodpeckers, in most cases with scores of holes." 



The other pertinent ol)servaiioii is: 



