UTILITY OF BIRDS IN WOODLANDS. 91 



other insectivorous creatures, without trouble or expense to 

 man, and without appreciable injury to his great woodland 

 interests. 



Birds attain their greatest usefuhiess in the woods, mainly 

 because the conditions there closely approach the natural, 

 and organic nature has an opportunity to adjust her balances 

 without much human interference. Man may be supreme in 

 the garden, field, or orchard, but in the woods nature reigns. 

 There her laws, unhampered, operate for the good of her 

 children. 



THE RELATIONS OF THE BIRD TO THE TREE. 



A mere glance at the economy of the forest shows us a 

 series of interrelations and interdependences existing be- 

 tween the bird and the tree. Mr. Frank M. Chapman thus 

 indicates tersely and clearh' the nature of these relations : — 



Between birds and forests there exist what maj' be termed primeval, 

 economic relations. Certain forest trees 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. Here, then, Ave have an undisturbed set of economic relations : 

 (1) the tree; (2) the insect, which lives in the tree, preys upon it, and 

 may assist in the fertilization of its blossoms ; (3) the bird, which also 

 finds a home in the tree, and, feeding upon insects, prevents their un- 

 due increase. Hence it follows that the existence of each one of these 

 forms of life is dependent upon tlie 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. Consequently, there has been established what is 

 termed "a balance of life," wherein there is the most delicate adjust- 

 ment between the tree, the insect, the bird, and the sum total of the 

 conditions which go to make up their environment. The more trees, 

 the greater the number of insects, and hence an increase not only in 

 food supply for the birds, but an increase in the number of nesting 

 sites. ^ 



Nearly all the wood birds are dependent upon trees. 

 Destroy the trees, and some of the insects might find new 

 food in the crops of the farmer, but the birds lose their home 



• The Economic Value of Birds to the State, by Frank M. Chapman. Sev- 

 enth Annual Report of the Forest, Fish and Game Commission of New York 

 State, 1903, p. 6. 



