CONTENTS 



Page . 

 Spraying experiments against the grape leafhopper in the Lake Erie Valley 



• in 1911 Fred Johnson. . 1 



Introduction '. - 1 



Treatment of nymphs of the grape leafhopper with contact sprays 1 



Field experiments with tobacco extracts 2 



Vineyard experiments in 1911 3 



Use of combined contact and poison spray 9 



Effect of grape leafhopper control on quality of fruit 10 



Conclusion 12 



The grape-berry moth (Polychrosis viteana Clem.), Fred Johnson and A. G. 



Hammar 15 



Introduction 15 



History 17 



Origin and distribution 18 



Food plants 20 



Occurrence of the grape-berry moth in destructive numbers 21 



Habits of the adult or moth 22 



Habits and character of injury of the larva 23 



Destructiveness of the larva 26 



Other insects whose injury to grape berries resembles that caused by the 



larva of the grape-berry moth 26 



Description 28 



Seasonal history 30 



Life-history studies in 1909 30 



Spring brood of moths 30 



Time of emergence of spring brood of moths 30 



Oviposition of spring-emerging moths in confinement 31 



Length of life of spring brood of moths 32 



First generation _ 32 



Incubation period of first-brood eggs 32 



Length of feeding period of first-brood larvae 33 



Length of pupal stage of first-brood pupae 33 



Time of emergence of first-brood moths 34 



O v r iposition of first-brood moths 35 



Hibernation of first-brood pupae 36 



Length of life cycle of first generation 37 



Second generation 38 



Incubation period of second-brood eggs 38 



Length of feeding period of second-brood larvae 38 



Date second-brood larvae leave fruit 39 



Miscellaneous rearing records for the seasons of 1907 and 1908 11 



Summary of life-history studies of the grape-berry moth 44 



Parasitic enemies 45 



Degree of vineyard infestation in Erie County. Pa. .". . . 49 



