154 SKiH-D-EBAOS, Food of Nuthatches and Chickadees. LApril 



mile — enough for four ordinary sized orchards — or the average 

 conditions existing in the better part of the State. As the worst 

 period of insect attack is during and after the breeding season, 

 this would allow six birds to each orchard. 



Nineteen Chickadees contained a total of 830 insect forms, a 

 large majority of which were noxious, and the remainder of a 

 doubtful character as regards their value. Thus the Chickadees 

 which it would be possible to secure in a fair sized orchard, a 

 half-dozen, would consume at least 275 forms a day, but probably 

 350 would be a much fairer estimate, as the larvae are quite 

 rapidly digested and many were so finely divided as to render 

 numerous individuals wholly indistinguishable. Now if these birds 

 could be persuaded to nest here and rear their young, which 

 would probably average five in number, 1200 insects would be 

 required per day to feed the young and old birds. Professor 

 Forbush states that 5000 canker-worms will strip a large apple 

 tree. Thus the number of insects eaten would be sufficient to 

 prevent the defoliation of a large tree every four days, and young 

 trees in proportion, with no expense whatever to the farmer for 

 labor or insecticides. Of course these compilations are largely of 

 a speculative character, as unfortunately we have but few experi- 

 ments and little accurate data, but they cannot but be highly 

 suggestive. 



Value of Winter Residence. 



But this fails to take into account the large number of eggs 

 eaten in the winter, from which the larvae, when hatched, might 

 be impqssible to destroy — as shown by the observations of Prof. 

 Forbush cited above. Again, the destruction of adult insects and 

 larvaj during the winter is far more valuable than later, because 

 they are mostly the ones which lay the eggs in the spring and 

 thus keep up the life cycle. There are but few other birds 

 present here in winter to perform this work, and these two birds 

 also secure their food from places where no other birds present 

 at that time of year would search for it. In this they form a 

 well balanced couple, the Nuthatch securing his food from the 

 rough bark of the main trunk while the Chickadee pecks away at 



