Montana State Library 



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MONTANA INSECT PESTS 1941 AND 1 942 

 Twenty-ninth Report of the State Entomologist 



Harlow B. Mills 



INTRODUCTION 



The insect pests which plague the rancher and farmer in Mon- 

 tana present an ever-changing picture. This is true for at least two 

 reasons. First, the pests of importance are likely to change from 

 year to year, the dry years having their more or less typical com- 

 plex of injurious forms, and the wet years reducing some of them 

 and making conditions favorable for a new group; further, new 

 pests are appearing in the State bringing with them new problems. 

 Second, in the light of new research findings better control meth- 

 ods are being developed, both in Montana and outside of the State, 

 which necessitate the constant inspection and revision of the ap- 

 proved methods of control. The control of grasshoppers and Mor- 

 mon crickets is a good example of this. The last decade has seen 

 many advances in our methods of attacking these problems. Sur- 

 vey methods have been developed and refined, bait formulae have 

 been improved and reduced in cost, and the mechanics of mixing 

 and spreading baits have taken great strides forward, largely 

 through the efforts of the United States Bureau of Entomology and 

 Plant Quarantine. 



The main efforts of this office have been directed toward the 

 control of the major pests, either through the administration of 

 field control campaigns, or through the preparation of circulars 

 describing approved methods of insect control. More than 300 

 inquiries on the control of a great variety of harmful animals are 

 received and answered annually. 



During the past year 44 single-page pamphlets, many of them 

 illustrated, were prepared by this office and published by the 

 Montana Extension Service. These circulars, Series A, Nos. 1 to 

 44, are available from County Agents or from the Montana Ex- 

 tension Service, Bozeman, Montana. 



Over a period of years the involved states in cooperation with 

 the Bureau of Entomology and Plant Quarantine have developed 

 a good organization for the large-scale control of regional insects 

 of migratory habits. Control operations in Montana, under the 

 joint direction of the State Entomologist's Office and this Bureau, 



