UNITED STATES DEPARTMENT OF AGRICULTURE 



BULLETIN No. 901 i 



Contribution from the Bureau of Entomology 

 L. O. HOWARD, Chief 



s&f<&3i. 



Washington, D. C. 



PROFESSIONAL PAPER 



December 13, 1920 



GRAPEVINE FLEA-BEETLES. 



By DWIGHT ISELY, 



Scientific Assistant, Deciduous- Fruit Insect Investigations. 



CONTENTS. 



Introduction 1 



History 2 



The grapevine flea-beetle 4 



Description of stages 4 



Distribution 6 



Food plants 6 



Habits 7 



Life history 7 



The lesser grapevine flea-beetle 11 



Description of stages 11 



The lesser grapevine flea-beetle — Continued. 



Distribution 13 



Food plants 13 



Habits 13 



Life history 14 



Economicimportance 20 



Predatory enemies 22 



Methods of control 23 



General summary 24 



Literature cited 26 



INTRODUCTION. 



The grapevine flea-beetle (Altica chalybea 111.) is a grape pest 

 which, in the period of its most destructive activity in early spring, 

 eats out the swelling buds, causing severe injury in restricted locali- 

 ties. It is one of the best known and most widely distributed of the 

 insect enemies of the grape. No other is the source of so many com- 

 plaints to the Bureau of Entomology, and American entomological 

 literature is full of references to it. In general its life history is well 

 known, yet, in spite of this, occasional discrepancies occur in ac- 

 counts of its life history that have never been reconciled with the 

 usually recorded observations. These discrepancies are usually 

 disposed of by attributing them to the variation of individual beetles. 



A study of the life history of the grapevine flea-beetle was under- 

 taken by the writer during the season of 1916 for the purpose of 

 comparison with that of a smaller flea-beetle also attacking grape. 

 A close similarity between the smaller beetle and the typical species 

 was noted, but the differences, particularly in seasonal history and 

 habits, were so well marked and so constant that the writer was 



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