THE PRINCIPAL INSECT ENEMIES OF GROWING WHEAT. 
INTRODUCTION. 
There are numerous insects, the number running into the hundreds, 
which feed on and injure growing wheat. Most of these insects are 
of rare or chance occurrence, and have no economic importance what- 
ever, although the fact that they are found on wheat often leads the 
farmer to be curious about them or unnecessarily arouses his fears. 
The great proportion of the losses to wheat fields which is charge- 
able to insects is due to the attacks of less than half a dozen species. 
These, in the order of their importance, are the chinch bug, the Hes- 
sian fly, the wheat midge, and the grain plant louse. Of second-rate 
importance are such insects as the wheat strawworms, the wheat bulb 
worm, army worms, cutworms, and various sawflies. Then there fol- 
lows a great horde of insects of minor importance which need not be 
considered in this connection. This is leaving out of consideration the 
locusts, or grasshoppers, including the Rocky Mountain, or migratory 
species, which occasionally injure wheat, but such injury is unusual 
and as a rule limited to migrations of locusts from one section to 
another, which are of infrequent occurrence nowadays, at least in the 
principal winter wheat growing regions, and have never been note- 
worthy except in the western districts. 
The reason for the excessive damage by the various grain pests noted 
in this country is not hard to discover. Our system of growing the 
same grain crops over vast areas year after year furnishes at once the 
very best conditions for the multiplication of the insect enemies of 
such crops. In addition to this is the fact that America, with its long, 
hot summers, presents the most favorable conditions for the multipli- 
cation of most insects. These two reasons undoubtedly account for 
the far greater losses experienced in this country as compared with 
Europe, the summers of which are very cool and short. Furthermore, 
in Europe farming is on a much more intensive scale. The holdings 
are small and carefully inspected, and any insect outbreak is promptly 
taken hold of, and in addition to this a regular system of rotation of 
crops is often practiced. 
The losses occasioned by the insects mentioned above exhibit a wide 
range in different years, due as a rule to favorable or unfavorable cli- 
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