UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 807 
Contribution from the Bureau of Entomology 
L. O. HOWARD, Chief 
jlW^fl. 
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 
Description 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 (Bruchus ruflmcmus Boh.). The practi- 
cal impossibility 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," p. 22. 
132902°— 19— Bull. 807 1 
