ENTOMOLOGY 



The following is a brief summary of the Entomologist's work 

 and the conditions he has found in various parts of the State. More 

 detailed information is given in his annual report. 



European corn borer. The activities of the past season have 

 shown a comparatively slight extension of the territory infested by 

 this insect in the Schenectady area and a material increase in the 

 western section, this latter due in all probability to the fact that 

 there was no time in the fall of 19 19 to determine fully the area 

 then infested, and thus the increase recorded in the Entomologist's 

 report is more apparent than real. 



The developments of the past season have again indicated but 

 one generation for the New York areas, while certain data brought 

 to attention during the past few months suggest that in eastern 

 Massachusetts there may have been but a partial second brood 

 each session instead of the previously supposed two complete gen- 

 erations. This of itself indicates less difference between the infested 

 area in New England and the New York sections than previously 

 had been supposed to exist. 



It is furthermore worthy of note that a very small second generation 

 developed in both the infested areas in New York and in Canada 

 in 1921. 



The discovery in 1920 of the European corn borer in Ontario, 

 Canada, one infestation just east of Buffalo and another centering 

 approximately upon St Thomas, has had a marked influence upon 

 the situation. It has demonstrated, for example, the impossibility 

 of attempting extermination with such extensive and widely dis- 

 tributed infestations. The conditions, climatic and agricultural, in 

 Canada are practically identical with those obtaining in New York 

 State and are of particular interest, because in the vicinity of St 

 Thomas large areas of field corn were seriously damaged, some 

 70 to 90 per cent of the stalks being infested and approximately 50 

 per cent of the ears. The commercial damage in one of the more 

 seriously affected fields was placed at from 20 to 25 per cent. This 

 was produced by one generation and in a section where the insect 

 presumably had not been sufficiently abundant the preceding season 

 to attract general notice. It obviously follows that such conditions 

 may develop in the infested areas in New York State and that with 

 substantially no warning, unless precautions are adopted to prevent 



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