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ern Illinois has suffered for the last three years, have been de- 

 livered first, each year, upon the fields of winter wheat, no spring 

 grain but oats being raised in that entire region; and our recent 

 observations in Northern Illinois, where winter wheat has lately 

 been introduced again to some extent, show that there likewise 

 this lias suffered scarcely less, in several instances, than spring 

 wheat beside it. It is probable, however, that where both varie- 

 ties are raised, the spring wheat will usually be worst attacked; 

 but certainly if only winter wheat is grown, this will afford every 

 necessary opportunity for the multiplication of the chinch bug. 



4. The iemporary abandonment of corn in regions where small 

 grains are the principal crop. This expedient was suggested by 

 observations made in the wheat regions of Washington county, 

 where nature made for us, in 1886, an experiment on a large scale, 

 showing the result of a lack of food for the midsummer brood of 

 the chinch bug. The few corn fields in that region being early 

 destroyed by insects and drouth, the breeding of the bugs was cut 

 short in the corn, and the adults were forced to desert the fields 

 in midsummer. Most of them consequently flew to the woods and 

 lived principally, during the remainder of the season, upon certain 

 woodland grasses. The number of the hibernating generation was 

 thus cut down, and those surviving passed the winter almost 

 wholly in the woodlands, with the consequence that fields at some 

 distance from woods were nearly or quite free from attack the 

 following sirring. A general burning of the woods and thickets at 

 the proper season, as recommended under another head, would 

 probably have almost wholly protected this entire region. 



5. Culture of crops not affected by the chinch bug. The most 

 important of these are clover, buckwheat, potatoes, turnips, and 

 the root crops generally ; flax, hemp, beans, castor beans, melons, 

 strawberries, and all the fruits. Oats and the common meadow 

 grasses are usually less damaged than wheat, rye, barley, Hun- 

 garian, and millet. 



6. Heavy fertilization, both of the ground before planting, and 

 of the surface where the crop is attacked. This method takes 

 effect both by supporting the plant under the drain of insect in- 

 jury, and by causing a more luxuriant and thicker growth of 

 vegetation, which shades the ground and renders it moist, thus 

 supplying conditions unfavorable to the multiplication of the chinch 

 bug. It is, by many, supposed that the bugs prefer an unthrifty 

 vegetation to one in vigorous growth, but this is certainly not in- 

 variably the case. Fields of corn, side by side, one fertilized and 

 the other not, are often equally infested by this insect, the con- 

 spicuous difference in condition being due wholly to the greater 

 resisting power of the stimulated plants. This practice has like- 

 wise the advantage of forcing the development of the crop, thus 

 pushing it out of the way of early injury. . X 



An experiment recently conducted for me by Mr. Samuel Bart- 

 ley, of Edgewood, bears on the utility of this method. A plot of 



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