WOODPECKERS. 



145 



a. Destruction of Seeds. 



Dendrocopus major alone of the woodpeckers eats large 

 quantities of coniferous seeds. It 

 wedges the cones, which it has 

 plucked from trees, in a cleft in the 

 bark, or in an angle between a stem 

 and a branch, and opens them out 

 and removes the seeds with its bill. 

 We can distinguish between the 

 action of the woodpecker and cross- 

 bill in this respect. Frequently the 

 ground under a tree is covered with 

 opened-out cones. Also walnuts, 

 hazel-nuts, acorns, and other fruits 

 are eaten by the great woodpecker. 

 The damage done is not, however, 

 very serious, as woodpeckers are solitary birds. 



Fig. 57. Cone of Scots pine 

 attacked by woodpecker, 



b. Peeking Holes in sound Trees, 



The black and the great woodpecker do most of this damage, 

 and attack isolated trees and saplings. The woodpecker also 

 attacks freshly planted saplings of oak, beech, acacia, exotics, 

 etc., and the reason for its doing so is not very clear ; in 

 coniferous woods it may thus free the beak from resin derived 

 from the cones it has been attacking. 



Older trees are also attacked, such as avenue-trees (poplars, 

 limes), oaks occurring in coniferous forests, boundary trees, etc. 

 Most of this damage is done during spring and early summer 

 but it is too rare to be of any practical importance. 



c. Girdling Trees. 



The same two woodpeckers, while hanging to the trunk by 

 their feet with the support of their tail feathers, encircle trees 

 with rings of holes arranged horizontally. A callus forms at 

 each hole, but is pecked at again and again until quite a ledge 

 has been made round the tree. Trees may sometimes be seen 

 with several such ledges, one above the other, resembling the 

 rings on bamboos. The reason for these attacks on sound 

 trees has not yet been discovered (Fig. 58). 



F.P. L 



