PREFACE. 



The native birds are one of our nation's most valu- 

 able assets. Destroy them, and in a comparatively 

 few years the insects will have multiplied to such an 

 extent that trees will be denuded of their foliage, 

 plants will cease to thrive and crops cannot be raised. 

 This is not fancy but plain facts. Look at the little 

 Chickadee on the side of this page. She was photo- 



fraphed while entering a bird box, with about twenty- 

 ve plant lice to feed her seven young; about two hun- 

 dred times a day, either she or her mate, made trips 

 with similar loads to feed the growing youngsters. 



It has been found, by observation and dissection, 

 that a Cuckoo consumes daily from 50 to 400 cater- 

 pillars or their equivalent, while a Chickadee will eat 

 from 200 to 500 insects, or up to 4000 insect or worm 

 eggs. 100 insects a day is a conservative estimate of 

 the quantity consumed by each individual insectiv- 



