well to leave the stubble unusually high to
insure a rapid spread of the fire. Burn refuse from the
threshing-machine, since this often harbors many larvae or pupae. Follow
the burning by deep plowing, because the burning cannot reach the
insects that are in the base of the plants. Delay the fall planting
until time for heavy frosts.

=The Potato Beetle; Tobacco Worm.= The potato beetle, tobacco worm,
etc., are too well known to need description. Suffice it to say that no
good farmer will neglect to protect his crop from any pest that
threatens it.

The increase, owing to various causes, of insects, of fungi, of
bacterial diseases, makes a study of these pests, of their origin, and
of their prevention a necessary part of a successful farmer's training.
Tillage alone will no longer render orchard, vineyard, and garden
fruitful. Protection from every form of plant enemies must be added to
tillage.

[Illustration: FIG. 170. SPRAYING THE ORCHARD
One way of increasing the yield of fruit]

In dealing with plants, as with human beings, the great object should be
not the cure but the prevention of disease. If disease can be prevented,
it is far too costly to wait for it to develop and then to attempt its
cure. Men of science are studying the new forms of diseases and new
insects as fast as they appear. These men are finding ways of fighting
old and new enemies. Young people who expect to farm should early learn
to follow their advice.

=EXERCISE=

How does the squash bug resemble the plant louse? Is this a true
bug? Gather some eggs and watch the development of the insects in a
breeding-cage. Estimate the damage done to some crops by the
flea-beetle. What is the best method of prevention?

[Illustration: FIG. 171. AN APPLE TREE SHOWING PROPER CARE]

Do you know the large moth that is the mother of the tobacco worm?
You may often see her visiting the blossoms of the Jimson weed.
Some tobacco-growers cultivate a few of these weeds in a tobacco
field. In the blossom they place a little cobalt or "fly-stone" and
sirup. When the tobacco-worm moth visits this flower and sips the
poisoned nectar, she will of course lay no more troublesome eggs.

SECTION XXXIV. THE COTTON-BOLL WEEVIL

So far as known, the cotton-boll weevil, an insect which is a native of
the tropics, crossed the Rio Grande River into Texas in 1891 and 1892.
It settled in the cotton fields aro