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Mr. Webster presented the following paper : 



THREE YEARS' STUDY OF AN OUTBREAK OF THE CHINCH BUG 



IN OHIO. 



By F. M. Webster, Wooster, Ohio. 



As compared with Illinois and the States west of the Mississippi and 

 north of the Arkansas rivers, Ohio had, until 1895, never witnessed an 

 outbreak of chinch bug. As a consequence, almost the only farmers 

 who had any acquaintance whatever with the pest were snch as had 

 had experience with it in the States above mentioned, few others being- 

 able to recognize it when it appeared in their fields. There had been a 

 slight attack in extreme southern Ohio in 1873, and a more severe one, 

 located more centrally, in 1887 and 1888, but even in these cases the 

 ravages were not so very severe, except locally. In traveling about 

 over the State I have frequently observed it in limited numbers and 

 learned of its previous occurrence in various localities in noticeable 

 though not in destructive numbers from people who could only describe 

 them as " being present at harvest time and among corn at the time of 

 cutting and curing the fodder, and having the odor of bedbugs/' It 

 was therefore with little concern that in the summer of 1891 I noted 

 them in limited numbers over the area indicated in fig. 1 by horizontal 

 lines, and much more abundant where these are crossed by oblique lines. 

 There did not appear to be any special danger, as the threatened out- 

 break would probably have failed to materialize had the spring of 1895 

 been one during which there was an average rainfall. But the season 

 of 1895 proved a very dry one, and I fully expected trouble from some- 

 where, but up to June 25 no complaints were received from farmers, 

 and I came to the conclusion that Ohio was certainly not a locality at 

 all congenial to chinch bugs. Within two weeks, however, that opinion 

 was entirely reversed, and hundreds of farmers appeared to discover 

 the pest on about the same dates, and a perfect deluge of letters came 

 pouring in, but, strangely enough, very few of them came from within 

 the area where the pest had been observed the previous year, and 

 consequently where they might apparently be the most confidently 

 expected. In fig. 2 the area of attack and the relative severity 

 are indicated as in map 1, and it will be observed that in one county 

 only, Wyandot, was the attack as severe as during the precediug year, 

 while over a considerable portion of the area where bugs were observed 

 in limited numbers in 1891 we had no complaints of their appearance 

 at all in 1895. Attention is here called to the isolated localities of 

 occurrence that year, as these will prove of especial interest when we 

 come to study the outbreak of the year 1896, besides indicating locali- 

 ties where we distributed Sjxyrotrichum. The autumn of 1895 was very 

 dry, and almost the entire fall brood of chinch bugs must have gone into 

 winter quarters in a healthy condition. The spring of 1890 opened with 



