UNITED STATES DEPARTMENT OF AGRICULTURE 



f BULLETIN No. 1103 iMf 



s^'^^u 



Washington, D. C. 



July, 1922 



SUMMARY OF INSECT CONDITIONS THROUGH- 

 OUT THE UNITED STATES DURING 1921. 



By J. A. Hyslop, Entomologist in Charge, Insect Pest Survey, 

 Bureau of Entomology. 



CONTENTS. 



Page. 



Introduction 1 



Corn earworm 5 



Hessian fly 9 



Chinch bug 11 



Green bug 15 



Pale westei-n cutworm 19 



Alfalfa weevil 21 



Sorghum webworm 24 



European corn borer 28 



Camphor scale 31 



Page. 



Mexican beau beetle 32 



Sweet-potato weevil 34 



Potato leafhopper 37 



Seed-corn maggot 39 



Cotton boll weevil 42 



Pink boUworm 43 



Japanese beetle 44 



Satin moth 46 



Gipsy moth 48 



Brown-tail moth 50 



INTRODUCTION. 



The object of the insect-pest survey is to collect accurate and de- 

 tailed information on the occurrence, distribution, ecology, and rela- 

 tive clestructiveness of insect pests throughout the United States, and 

 to study this data from month to month and year to year with relation 

 to the several factors that influence insect abundance. The results 

 to be obtained from this undertaking over a series of years are mani- 

 fold; we should be able to throw light on the reasons for the cyclic 

 appearance of certain insect pests, the gradual shift of regions of 

 destructive abundance, the limiting barriers to normal dispersal, the 

 directive influences that determine the paths of insect diffusion, and 

 the relation of climatology, geography, topography, and geology, as 

 well as biological complexes, to insect distribution and abundance. 

 This is the necessary foundation for the next advance step in eco- 

 nomic entomology, entoTnological forecasting. 



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