UNITED STATES DEPARTMENT OF AGRICULTURE 



h BULLETIN No. 807 



Contribution from the Bureau of Entomology 

 L. O. HOWARD, Chief 



Washington, D. C. 



PROFESSIONAL PAPER 



January 27, 1920 



THE BROAD-BEAN WEEVIL. 



By Roy E. Campbell, 

 Scientific Assistant, Truck Crop Insect Investigations. 



CONTENTS. 



Page. 



Introduction 1 



Doscription 2 



■Synonymy 3 



Records of occurrence in California^ 3 



Distribution in California 4 



Spread in California 4 



Dissemination 4 



Nature of damage 5 



Extent of damage 6 



Life history 8 



Seasonal history 11 



Page. 



Germination tests of infested seeds. 13 



Natural enemies 14 



Control measures 15 



Dry heat 15 



Fumigation 16 



Holding over seed 17 



Late planting 18 



Recommendations 21 



Summary 21 



Literature cited 22 



INTRODUCTION. 



The growing of broad or horse beans in California during the last 

 few years has been seriously handicapped everywhere by the presence 

 of the broad-bean weevil {Bt'uchus ru^mcmus Boh.). The practi- 

 cal impossibilit}' of growing uninfested beans caused the early aban- 

 donment of a considerable acreage. The greatest abandonment, how- 

 ever, followed the ruling, according to the Federal Food and Drugs 

 Act, that weevil-infested broad beans are adulterated food, and that 

 their shipment was prohibited in interstate commerce. 



The Bureau of Chemistry first ruled that beans infested " to any 

 material extent " could not be shipped (4) ,^ but later changed the rul- 

 ing to allow shipment to any lot which contained " not more than 

 15 per cent of wormy or weevil-infested beans" (5). The 15 per 

 cent limit is tentative only. Acting under this ruling, a shipment 

 of broad beans from a San Francisco broker was seized in New 

 York, after having been found to be over 25 per cent infested. The 

 broker was tried for violating the Food and Drugs Act, convicted 



1 Numbers in parentheses refer to "Literature cited, 

 132902°— 19— Bull. 807 1 



p. 22. 



