7 s THE RELATION OF SPARROWS TO AGRICULTURE. 
was crammed lull of the seeds of crab-grass. The much smaller con- 
Bumpl ion of ragweed, amarant h, Lamb's-quarters, and polygonum than 
on the pari of tree, white-throated, and song sparrows is probably due 
to the smaller and less powerful digestive organs of the chipping 
sparrow. 
No small service is rendered in destroying weed seed, but the utility 
of the species is manifested most strikingly in its animal food, three- 
fourths of which consists of noxious insects, principally caterpillars, 
weevils, grasshoppers, and Leaf-beetles. Of the 38 percent of animal 
matter, weevils constitute 6 percent; leaf-beetles, - percent; other 
Coleoptera, including predaceous ground-beetles, dung beetles, click- 
beetles, and .May-beetles, collectively, 3 percent; caterpillars, 9 per- 
cent; grasshoppers, LO percent; and miscellaneous animal matter, 
consisting of leaf-hoppers, I rue bugs, ants, spiders, and parasil ic wasps, 
8 percent. The maximum monthly average of weevils, 16 percent, 
is attained in May. In June, when 1)3 percent of the food is com- 
posed of insects, grasshoppers form 36 percent, caterpillars 25 per- 
cent, and leaf-beetles 6 percent. 
On the one side only 1 percent of the food consists of useful insects 
(predaceous beetles and parasitic wasps), while more than 25 percent 
is made up of insect pests; and on the other side, grain composes only 
4 percent, in contrast to w r eed seed, which constitutes 40 percent. 
These figures clearly show the good service rendered to agriculture. 
The food habits of this sparrow will receive further consideration 
in connection with those of the next species — the field sparrow. 
FIELD SPARROW. 
(Spizella putriUa and Spizella p. arenacea.) 
The field sparrow (see fig. 16) summers in the northern half of the 
United States east of the Rock}' Mountains and in southern Canada, 
and winters in the Southern States. 
It can perhaps best be distinguished from the many small species 
of ground-colored birds by its reddish beak. It is thoroughly com- 
monplace in appearance, and in habits is much shyer than the chip- 
ping and song sparrows, which may be called dooryard birds. Often 
seen in the same weed patch with these sparrows, it is nevertheless. 
as its name indicates, a lover of open lands. Here it builds its nest. 
generally among some small briers, and during the season rears two 
to three broods Of three or four each. Its food habits are very simi- 
lar to those of the chipping sparrow, as would naturally b<' expected; 
since both belong to the same genus. Forbush has found it preying 
on plant lice, tent caterpillars, cankerworms, and the caterpillars of 
the brown-tail moth.' 
M.i>s. Crop Bept., I'.ull. :;. pp. 38 86, July, 1900, 
