U. S. D. A., B. E. Bui. 116, Part H. D . F> L L> i ssue d December 18, 1912. 



PAPERS ON DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 



THE GRAPE-BERRY MOTH. 



(Polychrosis viteana Clem.) 



By Fred Johnson and A. G. Hammar, 



Entomological Assistants. 



INTRODUCTION. 



The grape-berry moth, Polychrosis viteana Clem. (PL IV), is an 

 insect enemy of the grape of long standing in the . vineyards of the 

 Lake Erie Valley. Since the first reports of its serious injury to 

 the grape crop near Hudson, Ohio, in 1868, it has been an almost 

 continual menace to grape production in vineyards located along 

 the shores of Lake Erie from Sandusky in Ohio eastward into 

 Pennsylvania and New York. Most of the data dealing with this 

 insect cover a series of life-history records and field experiments con- 

 ducted during the seasons from 1907 to 1909, inclusive, in connec- 

 tion with the investigations of the grape rootworm and other insect 

 pests of the grapevine which have been carried on at North East, 

 Pa., by the section of the Bureau of Entomology engaged in decid- 

 ciduous fruit insect investigations under the direction of Mr. A. L. 

 Quaintance. 



Before entering into a discussion of the detailed life-history studies 

 and remedial measures, a brief resume of an historical nature is given, 

 showing the attention this insect has received from earlier entomolo- 

 gists. In treating of its origin and distribution it is pointed out that 

 for many years it was confused with the European grape-berry moth, 

 Eudemis botrana Schiff., an insect which is very destructive to the 

 berries of grapes in the vineyards of southern Europe and to which it 

 is closely related and bears a very close resemblance, both in appear- 

 ance and in the manner in which it attacks the grape. 



Earlier entomologists credited the grape-berry moth with having a 

 number of food plants, but the studies of the late Prof. M. V. Slinger- 

 land in 1903 and 1904 indicate that several other species of Polychrosis 

 have been confused with P. viteana, and that the latter feeds and repro- 

 duces only in the berries of grapes, wild and cultivated. His conclu- 

 sions are borne out by the observations made during this investiga- 

 tion, for in no case has this insect been reared from anything but 



blossom clusters and berries of the grape. 



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