BIRDS OF NEW YORK 47 



quantities of food. This is especially true of growing birds which require 

 one-half their own weight of food daily. As the young of our insectivorous 

 birds are being reared while our crops are in the midst of their growth, 

 it is evident that the resultant destruction of insects for food occurs at 

 just the time of year to ' be of most service to the agriculturist. When- 

 ever undue increase of insects begins, birds of the neighboring region invade 

 the infected area and destroy the injurious species before they have become 

 a consuming plague. In sections of the country, however, where nearly 

 all the land is under cultivation and there are few breeding sites for birds, 

 it is impossible for the few remaining birds to hold the insects in check, 

 and thus arises the necessity of spraying on an extensive scale. During 

 the spring of 1898 in the town of Brighton, Monroe county, the author 

 noticed that several orchards were practically defoliated by cankerworms. 

 On visiting orchards to which the scourge was spreading, I observed many 

 species of birds coming from the surrounding country and feeding upon 

 the worms. While seated in a small orchard, thirteen species of birds 

 were noticed in the course of half an hour coming and devouring the worms 

 as fast as they could be swallowed, or gathering mouthfuls and carrying 

 them away to feed their young which were oftentimes at a considerable 

 distance. Species like the Kingbird and Phoebe which rarely prefer cater- 

 pillars as diet, and others like the Bobolink, Red- winged blackbird and 

 Vesper sparrow which are seldom seen feeding in the orchards, were coming 

 and carrying away the worms for their nestlings. Cuckoos, orioles, cat- 

 birds and cedarbirds were noticed among the foliage swallowing the larvae 

 at the rate of fifteen to forty a minute. There seemed to be little inter- 

 ruption of this work even during midday, but in the morning and late 

 afternoon there was a decided increase in the birds visiting the orchard 

 for the cankerworms. There could be no doubt if the birds had been 

 in sufficient number in the immediate vicinity where this plague of cater- 

 pillars started they would have held them in check and prevented the 

 destruction of crop and leaves in several orchards. It is probable that, 

 in nature, worms of this kind rarely increase to such an extent as to defoliate 



