47 
every year. It is a fact of common observation that it is the neglected 
farm, vineyard, or orchard filled with weeds or wild growth which is 
certain to be stocked with all the principal insect enemies; and, on the 
other hand, thorough and constant culture, with the removal and 
burning of prunings, stubble, and other waste, the collection and de- 
struction of fallen and diseased fruit, and the practice, where possible, 
of fall plowing to disturb the hibernating quarters of field insects, 
will almost certainly be accompanied by comparative immunity from 
insect pests. 
The vigor and healthfulness of plant growth has also much to do 
with freedom from insect injury. Strong, healthy plants seem to have 
a native power of resistance which renders them, in a measure, dis- 
tasteful to most insects, or at least able to throw off or withstand their 
attacks. A plant already weakened from any cause, however, seems 
to be especially sought after, is almost sure to be the first affected, 
and furnishes a starting point for general infestation. Anything, 
therefore, which aids good culture in keeping plants strong and 
vigorous, such as the judicious use of fertilizers, will materially 
assist In preventing injury. 
The constant cropping of large areas of land year after year to 
the same staple is largely responsible for the excessive loss from in- 
sects in this country as compared with European countries, because 
this practice furnishes the best possible conditions for the multiplica- 
tion of the enemies of such crops. A most valuable cultural means, 
therefore, is a system of rotation of crops which will prevent the 
gradual yearly increase of the enemies of any particular staple by 
the substitution every year or two of other cultures not subject to the 
attacks of the insect enemies of the first. 
With such insects as the Hessian fly, the squash borers, and many 
others which have regular times of appearance, much can be done 
by the planting of early or late varieties or by deferring seeding 
so as to avoid the periods of excessive danger. Wherever possible, 
varieties should be selected which experience has shown to be re- 
sistant to insect attack. Familiar illustrations of such resistant va- 
rieties in all classes of cultivated plants will occur to every practical 
man, and a better instance of the benefit to be derived from taking 
advantage of this knowledge can not be given than the almost uni- 
versal adoption of resistant American vines as stocks for the regenera- 
tion of the vineyards of France destroyed by the phylloxera and for 
the similarly affected vineyards of European grapes in California. 
In the case of stored-grain pests, particularly the Angoumois moth, 
or so-called “ fly weevil,” the chief danger in the South occurs while 
the grain is standing in shock or stack, after harvesting, during which 
period the insects have easy access to it. This source of infestation 
may be avoided by thrashing grain promptly after harvesting and 
storing it in bulk. This will prevent injury to more than the sur- 
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