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CHINCH BUG OBSERVATIONS IN IOWA IN 1894. 



L?y Hkkhekt Osborx, Ames, Iowa. 



Acting uuder a commission from the Department of Agriculture 

 received from Mr. Howard late in June, I took an extended trip through 

 the State, making careful observations in all localities in which the 

 chinch bug had appeared. I have submitted a full report, giving my 

 field notes in detail. The following matter is extracted from the clos- 

 ing pages of the report : 



To sum up the results of these investigations in as compact form as 

 possible it may be said that the crop first attacked this season was in 

 about 45 per cent of the cases wheat, in about 30 per cent barley, about 

 18 per cent rye, about 20 per cent oats, and 2 per cent corn. The attacks 

 in oats were in most cases where oats had been grown on corn land or 

 were adjacent to shelter for the bugs and where no other grain crop 

 was present, and also it would seem in most cases where oats were 

 planted early so that the bugs were able to commence work in the fields 

 as early as they would have in other grain crops. With regard to the 

 crop which had been on the ground a year before, it was, in the majority 

 of cases, corn where the preceding crop could be determined, about 55 

 per cent corn, about 35 per cent oats, about 7 per cent wheat, and about 

 2 per cent rye. This would indicate that if there is any importance to 

 be placed upon the sequence of crops that the bugs are more likely to 

 infest fields which have been previously in corn stalks. It seems prob- 

 able, however, that this sequence is simply a result of the ordinary 

 sequence of farm crops, wheat very commonly following corn. It would 

 seem by the records in some cases that there was a strong probability 

 that bugs hibernate in corn stalks, and it would seem wise to consider 

 these a probable source of danger. In regard to the method of hiber- 

 nation the record shows that practically in every instance there was 

 some kind of shelter within a very short distance of the infested fields, 

 and the evidence all points toward the movement of the bugs directly 

 from such slielter into adjacent fields, and in many cases without even 

 necessitating the taking to flight In a great majority of cases, 90 per 

 cent or more, the fields were directly adjacent to hedges or thickets or 

 timber belts, and in 75 per cent Osage orange hedges were the most 

 available shelter. In about 13 j)er cent of the cases the evidence showed 

 hibernation in grass or weeds, and in some of these cases there could 

 scarcely be a doubt that the hibernating bugs were protected in a heavy 

 growth of grass or weeds, and that they moved from these directly into 

 the adjacent grain fields. These observations, while of course simply 

 duplicating what has been recognized before, seem to show very forci- 

 bly the importance of destroying the rubbish alongside of the fields, 

 Avhere chinch bugs-have been present, as a means of protection for the 

 following season. If new in any respect it is in that they indicate so 



