ll of these observations have been made by field workers from the
Department of Agriculture, and no statement has been made that has not
been proved by the examination of many bird stomachs at different
seasons.

Highest of all in the list come the bluebirds. They are among the most
beautiful of our native birds, with their bright blue coats and soft red
breasts. They are sweet singers, and are among the first to return in
the spring to tell us of the return of summer. In addition to this they
have many good habits and absolutely no bad ones. More than
three-fourths of their food consists of insects,--beetles, grasshoppers
and caterpillars. The remainder is weed seeds and fruit, but there were
no reports of cultivated fruits being eaten by bluebirds. On the
contrary they eat the most undesirable of the wild fruit, chokeberry,
pokeberry, Virginia creeper, bitter-sweet and sumac, as well as large
quantities of ragweed seeds. Other birds are equally useful but none
combines usefulness with so much beauty and sweetness of song.

The tiny wrens are another class of wholly useful birds. Their food
consists almost entirely of insects with a very little grass-seed. They
search every tree, shrub, and vine for caterpillars, spiders and
grasshoppers.

Sparrows are almost equally useful. The tree sparrow, song sparrow,
chipping sparrow, field sparrow and snowbird or junco are all great
weed-seed destroyers. Many of them remain throughout the winter, when
they feed entirely on the seeds of weeds. Each bird eats at least a
quarter of an ounce of seeds per day, and they are often found by
thousands in a region. At least a half dozen varieties of birds are
feeding in the same ratio all over the country, reducing the crop of
next year's weeds. During the summer they turn to a diet composed partly
of insects and here again they help the farmer by eating the weevils,
leaf-beetles, grasshoppers, bugs and wasps that infest his crops.

The various species of swallows rank high as insect-eating birds. The
tree, bank, cliff and barn swallows and the purple martins all eat small
beetles, mosquitoes, flying ants and other high-flying insects, and the
number destroyed is almost beyond our power to imagine.

The most important service performed by swallows, however, is in the
South, where they migrate for the winter. There they feed largely on the
cotton boll-weevil, one of the most destructive of all insects, as we
have seen. The Department