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CIRCULAR No. 241 



LI R c 



'oberRi9£2 C E 



UNITED STATES DEPARTMENT OF AfrR^UL^URE 9 

 WASHINGTON, D. C. f _ ( 



LEAF HOPPERS INJURIOUS TO = CEREAL: 

 FORAGE CROPS 



By Herbert Osborn, Collaborator, Division of Cereal and Forage Insects, 

 Bureau of Entomology 



CONTENTS 



Page 



Introduction 1 



Nature and extent of injury 2 



Crops affected 4 



General habits of leaf hoppers 4 



Hibernation 5 



Life history in general 5 



Kelation to environment 6 



Natural enemies 7 



Birds 7 



Spiders 8 



Insects 9 



Remedial measures 10 



Cultural methods 10 



Burning dry grass 11 



Capturing the insects in hopperdozers or tar 



pans 12 



Page 



Remedial measures— Continued. 



Spraying ._ 12 



The more important species of leaf hoppers af- 

 fecting grain and forage crops 13 



The yellow-headed leaf hopper 13 



The tenderfoot leaf hopper 15 



The inimical leaf hopper 1 18 



The black-faced leaf hopper 21 



The striate leaf hopper 22 



Say's leaf hopper ___ 24 



The destructive leaf hopper. 

 The irrorate leaf hopper, . 

 The 6-spotted leaf hopper. 

 The potato leaf hopper. . . 

 The clover leaf hopper. 



26 

 28 

 29 

 31 

 32 

 Literature cited 33 



INTRODUCTION 



The leaf-hopper enemies of cereal and forage crops have not been 

 accorded the same notice that some other groups have received, but 

 there is good reason to assume that the losses they occasion, espe- 

 cially in meadows and pastures, are so considerable that they de- 

 serve much greater attention than they have been given. 



In early publications, including a report to the Division of Ento- 

 mology in 1890 {lJf-Y and a paper by Osborn and Ball (21), a number 

 of species occurring in the central part of Iowa were treated with 

 reports of some experimental studies in control. The most complete 

 discussion of the group, however, is contained in a publication issued 

 by the Bureau of Entomology in 1912 (19), from which consider- 

 able portions of this circular are taken and condensed, in which 

 the writer brought together the results of studies in the group and 

 especially the details of an extensive survey under the auspices of 

 the bureau during 1909 and 1910. In this circular much new in- 

 formation is made available regarding the life histories of these 

 insects, the conditions under which they thrive, and the best methods 

 that have been devised for curbing their numbers and activity. 



There are frequently so many species involved in the injury that 

 there has been a tendency, even among entomologists, to consign 

 them all to a limbo of undetermined species whose habits, life his- 

 tories, and food relations were unknown. 



Italic numbers in parentheses refer to Literature Cited, p. 33. 

 129811 — 32—1 



