UNITED STATES DEPARTMENT OF AGRICULTURE 

 BULLETIN No. 805 



Contribution from the Bureau of Entomology 

 L. O. HOWARD, Chief 



Washington, D. C. 



PROFESSIONAL PAPER 



December 15, 1919 



TWO LEAFHOPPERS INJURIOUS TO 

 APPLE NURSERY STOCK 



A. J. ACKERMAN, Scientific Assistant 

 Deciduous Fruit Insect Investigations 



CONTENTS 



Page 



Introduction . 1 



The Apple Leaf hopper ........ 2 



History 2 



Distribution 2 



Food Plants 3 



Character of Injury 4 



Extent of Injury and Influencing 



Factors 5 



Description of Stages 5 



Allied Species 6 



Life History and Habits 7 



Summary of Seasonal History . . 19 



Natural Enemies 20 



Page 



The Rose Leaf hopper 20 



History 20 



Synonymy 21 



Origin and Distribution 21 



Food Plants 21 



Character of Injury 22 



Description of Stages 22 



Life History and Habits ..... 23 



Summary of Seasonal History . . 28 



Natural Enemies 28 



Remedial Measures 29 



Summary 33 



Literature Cited 34 



WASHINGTON 



GOVERNMENT PRINTING OFFICE 



1919 



