Relation of Summer Birds to Western Adirondack Forest 419 



Sterling ('02, p. 18) suggests that .we must look at a forest not as a 

 mere collection of trees but as an organic whole, the result of actions 

 and reactions among all the factors found within its limits. " The 

 shade-enduring herbs and shrubs on the ground, the mosses and 

 lichens on tree trunks and branches, and a host of other vegetable 

 forms, are likewise a part of the forest whole, since they are products 

 of and entirely dependent upon the natural forest conditions tor their 

 maintenance." It is in order that these complex and vital relation- 

 ships may be more thoroughly understood that I present the estimates 

 which follow, showing the relation between forest trees and the 

 birds that frequent them. Dr. Frank M. Chapman (/03, p. 115) 

 calls attention to their vital interdependence. " Certain forests have 

 their natural insect foes to which they furnish food and shelter ; and 

 these insects, in turn, have their natural enemies among the birds, 

 to which the trees also give a home. . . . Hence it follows that 

 the existence of each one of these forms of life is dependent upon 

 the existence of the other. Birds are not only essential to the welfare 

 of the tree, but the tree is necessary to the life of the bird." We are 

 clearly warranted, therefore, in believing that each kind of tree in the 

 Adirondack mixed forest exerts an important and active influence in 

 forming the association of birds belonging to the region ; that certain 

 birds are found there because certain kinds of trees or shrubs are 

 dominant there, living not separately but in association. It is not 

 the single birch tree that constitutes an attraction, but rather the 

 birch as a participant throughout the Adirondack association that 

 makes it effective upon the bird life in the region. For instance, 

 the maple is a powerful agent in influencing bird life in an associa- 

 tion; but I once knew a grove of forty acres of pure maple which 

 did not attract a dozen species of birds in its summer prime. So 

 also an extended area of nearly pure beech woods is almost a solitude 

 in its expression of bird life; yet the beech, like the maple, is an 

 invaluable constituent of the Adirondack forest. 



There seems available only one method of estimating the propor- 

 tional values of the relationships existing between any species of 

 tree and the birds, and that is by a series of careful notes recording 

 such relationships as are observed, and a general summary based on 

 such data. It has been my method in bird study to make note of 

 the kind of tree, shrub, or bush in which any bird under observation 

 showed any activity of importance, either in locating its nest, search- 

 ing for food, or selecting a favorite station for singing. For 

 instance : " Dry Open Woods, July 7. Redstart's nest four feet up 

 in a birch sapling in the periphery of a thick clump of birch saplings." 

 Or : " Burn Lot, July 13. A male Chestnut-sided Warbler was 

 gleaning insect food in a clump of fire cherry saplings and flying 

 away with it, apparently to feed young." It is from multiplied 

 records like these that the deductions and generalizations are made 

 that follow in this report. 



The Birch and the Birds. The white, paper, or canoe birch is 

 found scattered throughout the Adirondack plateau, but tends to 



