UNITED STATES DEPARTMENT OF AGRICULTURE 

 BULLETIN No. 847 



Contribution from the Bureau of Entomology 

 L. O. HOWARD, Chief 



Washington, D. C. 



PROFESSIONAL PAPER 



August 9, 1920 



ROUNDHEADED APPLE-TREE BORER: 



ITS UFE HISTORY AND CONTROL 



By 



FRED E. BROOKS, Entomologist, 

 Deciduous Fruit Insect Investigations 



CONTENTS 



Page 



Introduction . 1 



History 2 



Distribution 2 



Food Plants _. 3 



Distribution as Affected by Native Host 



Plants 4 



Character of Injury 5 



Methods Used in Securing Breeding 



Material and Rearing the Insects . . 6 

 Cages Used for Rearing and Observing 



Borers • 6 



Page 



The Egg and Opposition 7 



The Larva 11 



The Pupa • . . 14 



The Adult 15 



Seasonal Phenomena of the Host Trees 

 as an Index to the Time of Develop- 

 mental Changes of the Insect .... 27 



Natural Enemies 29 



Methods of Control 30 



Summary 39 



Literature Cited 41 



WASHINGTON 



GOVERNMENT PRINTING OFFICE 



1920 



Eb^a 



