NEW YORK STATE MUSEUM 1 7 



carried by water currents or the wind. If this be true, it is quite 

 possible that the earher discovered western New York infestation 

 originated in the same way and may therefore be considerably more 

 recent than the one at St Thomas. This may be the factor which 

 explains the difference between the relatively small injury to corn in 

 the Silver Creek area as compared with the damage under very 

 similar conditions in the vicinity of St Thomas. 



There is another important matter which should be kept in mind. 

 During the fall of 1920 and the spring of 1921 an extensive clean-up 

 campaign centering upon Silver Creek and limited to the more badly 

 infested area was conducted by the federal authorities. This work 

 appears to have had little effect upon the general infestation, since 

 conditions the past season were very nearly the same in the cleaned-up 

 area as upon the adjacent Indian reservation where no work of this 

 character was possible. There is no doubt but that the clean-up 

 work destroyed many borers and materially reduced the infestation 

 as compared to what it might have been if there had been nothing 

 of the kind. There is a possibility that the benefits resulting from 

 this clean up may have been masked as it were by a considerable 

 driftage of moths from other infested areas, possibly from Ontario. 



There was a large increase the past season in the known infested 

 area in Canada, due mostly to the very limited scouting possible in 

 1920. There was also a great increase in the badly infested area 

 about St Thomas, which latter now comprises about 100 square 

 miles and shows much more serious and general injury to early 

 planted corn than the preceding year. There are numerous i-acre 

 to 5-acre lots of early com in that section which have sustained a 

 commercial loss approximating 70 per cent and in a few instances 

 the damage was so severe that no attempt was made to harvest either 

 corn or fodder, the stalks simply being cut, burned and the refuse 

 turned under. A mitigating feature is found in the fact that even 

 in this badly infested area injury to moderately late or late planted 

 corn, sweet, flint or dent was much less and particularly so in the 

 case of the last named. 



There was not serious injury in the infested areas of New York 

 State, although there were a number of fields in western New York 

 where a 50 to 70 per cent stalk infestation could be found. This 

 means appreciable damage in sweet corn, though not serious injury 

 to field corn. There was, however, the same relative variation in the 

 infestation in the New York areas as noted in the Canadian territory 



