UNITED STATES DEPARTMENT OF AGRICULTURE 



S^fr*^r*SU 



BULLETIN No. 730 



Contribution from the Bureau of Entomology, 

 L. O. HOWARD, Chief. 



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Washington, D. C. 



PROFESSIONAL PAPERS. 



December 24, 1918 



I. THE GRAPE CURCULIO. 1 



By Fred E. Brooks, 

 Entomologist, Deciduous -Fruit Insect Investigations. 



CONTENTS. 



Page. 



Introduction 1 



Economic history 2 



Synonymy 2 



Common names 2 



Distribution 3 



Food plants 3 



Recent injuries 3 



Resistance of certain grapes to curculio attack . 3 



The life cycle in brief 4 



Description 4 



Habits and activities of the beetles 5 



Activities of the larva? 12 



The pupa period 13 



The beetles in the fall 13 



Natural enemies 13 



Methods of control =■. 15 



Bibliography 16 



INTRODUCTION. 



In many localities in the eastern part of the United States the 

 grape curculio, Craponius inaequalis Say (PI. I, A — D), may be 

 classed as the most destructive insect attacking the grape. From 

 some .cause or causes which are not entirely clear, the insect is 

 markedly local in its occurrence and within the bounds of its general 

 range appears annually in destructive numbers in some localities 

 whereas it remains practically unknown to grape growers in other 

 districts nearby. In places where it is abundant it may be expected 

 to destroy each year from 35 to 100 per cent of fruit on all grapevines 

 that do not receive protection of some kind. 



The adult curculio is small and inconspicuous and a grape grower 

 will frequently lose within a short time an entire crop of fruit, that 

 had promised well, without being able to determine the nature of the 

 enemy that caused the loss. He will know only that the grapes while 



Note. — Acknowledgment is due Mr. C. R. Outright, who was employed temporarily 

 by the Bureau of Entomology to assist with the present investigation. 



i Craponius inaequalis Say; suborder Rhynchophora, family Curculionidae, tribe Ceutorhynchini, 

 subtribe Coeliodes. 



1°— Bull. 730—18 1 



