BLUE GROSBEAK VS. GRAIN. ' • 79 



Vegetable Food. 



The proper valuation of the vegetable elements of a bird's food 

 is of great importance, since upon this point largely depends the 

 attitude of the agriculturist toward the bird. The main question 

 is, Does the blue grosbeak appropriate an undue amount of the prod- 

 uct of field, orchard, and garden crops? 



Vegetable substances consumed by the blue grosbeak and consti- 

 tuting 32.4 percent of its food may be classified as follows: Grain, 

 14.25 percent; weed seed, 18.05 percent; fruit, 0.06 percent; and 

 miscellaneous. 0.04 percent. 



FBUIT. 



From present information it appears that cultivated fruits are not 

 molested by the blue grosbeak. All writers agree that the little 

 fruit eaten is wild, a conclusion supported by the results of the present 

 examination. Only two birds, both young, had eaten fruit of any 

 kind, and in each" case it consisted of a few bits of blackberry, un- 

 doubtedly wild. 



GRAIN. 



Grain constitutes 14.25 percent of the food of the birds examined. 

 Wheat was eaten by 6 of the total number, and amounts to 8.33 per- 

 cent of the entire subsistence. Corn was eaten by 4 birds and is 4.87 

 percent of the food, while oats, which form 1.05 percent, were con- 

 sumed by only 2 of the 51 birds. Probably all this grain was ob- 

 tained from cultivated crops. 



One grosbeak, collected in a wheat field in June, had eaten enough 

 of the milky cereal to make up 40 percent of it? stomach contents. 

 Three others from the same region in the same and the succeeding 

 two months had devoured wheat, which shows that this grain is 

 relished even in the riper stages. 



Apparently the com in the stomachs also came from the standing 

 crop, and while the blue grosbeak seems too small to be an active 

 depredator of such a well-protected grain, yet with its powerful beak 

 there is no doubt that it can as readily shear through the enveloping 

 husks as crack the kernels themselves. Referring to this latter point, 

 Wilson says of a captive bird : " I fed it on Indian com, which it 

 seemed to prefer, easily breaking with its powerful bill the hardest 

 grains." Notwithstanding this the bird does little damage. At all 

 events, no complaints of injury have been made. 



There is testimony, however, that the bird does some mischief in 

 oat fields. Doctor Fisher, of the* Biological Survey, has seen fiocks 

 feeding upon this cereal in Nebraska and in California, and the same 

 habit has been observed in Virginia. In general this occurs late in 

 summer.' After the nesting season blue grosbeaks change their 

 18848— Bull. 32—08 6 



