2 70 BoLLEs on the Tellow-bellied Woodpecker. [July 



get ehil)or;itc(l sap flowing downward, and probably that only. 

 If it is clal)()rated sap he wants, he would do much better to go 

 no further than the inner bark and cambium. The medullary 

 rays are so small in proportion to the size of a Woodj^ecker's bill 

 and tongue that he would receive but poor wages for his labor in 

 penetrating tliem. Of course in spring before the leaves are 

 fully out, the sap is very rich as it flows up, both in starchy and 

 albuminoid matters, and then it would be worth working for. 

 But as late as July and August, the upwartl flowing sap, while it 

 contains traces of tliese nutritious substances, must be very poor 

 in them. 



"■ I never thought of the question before, because I did not 

 know that Woodpeckei's bored for sap. I always supposed it was 

 insects and their larvae they were after." 



Summary. — From these observations I draw the following 

 conclusions : that the Yellow-bellied Woodpecker is in the habit 

 for successive years of drilling the canoe birch, red maple, red 

 oak, white ash and probably other trees for the purpose of taking 

 from them the elaborated sap and in some cases parts of the cam- 

 bium layer; that the birds consume the sap in large quantities 

 for its own sake and not for insect matter which such sap may 

 chance occasionally to contain ; that the sap attrac s many in- 

 sects of various species a few of which form a considerable part 

 of the food of this bird, but whose capture does not occupy its 

 time to anything like the extent to which sap drinking occupies 

 it ; that different families of these Woodpeckers occupy diflerent 

 'orchards,' such families consisting of a male, female and from 

 one to four or five young birds ; that the 'orchards' consist of 

 several trees usually only a few rods apart and that these trees 

 are reo"ularly and constantly visited from sunrise until long after 

 sunset, not only by the Woodpeckers themselves, but by numer- 

 ous parasitical Hummingbirds which are sometimes unmolested, 

 but probably quite as often repelled ; that the forest trees attacked 

 l)y them generally die, possibly in the second or third year of use ; 

 that the total damage done by them is too insignificant to justify 

 their persecution in well-wooded regions. 



