THE GRAPE ROOT-WORM 



WITH ESPECIAL REFERENCE TO INVESTIGATIONS 

 IN THE ERIE GRAPE BELT PROM 1907 TO 1909. 



INTRODUCTION. 



During the past decade the insect Fidia viticida Walsh (PL I), 

 a chrysomehd beetle known to the vineyardists of the Lake Erie 

 Valley as the '^ grape root- worm" beetle, which in the larval stage 

 feeds upon the roots of the grapevine, has become by far the most 

 destructive insect pest attacking the grape in that region. 



The following pages present the extent and findings of an investi- 

 gation conducted at North East, Pa., during the seasons of 1907, 

 1908, and 1909. These investigations were undertaken in order to 

 make a thorough study of the life history and habits of this insect, 

 to conduct experiments with a view to its control, and to make field 

 experiments to demonstrate the practical commercial value of those 

 methods giving greatest promise of effective results. 



Since the grape root-worm is a grape pest of long standing, a brief 

 resume of its history is given, both from the standpoint of entomolog- 

 ical classification and from that of the development of remedial 

 measures for its control. 



Its origin, distribution, and food plants are considered, brief de- 

 scriptions of allied beetles and of those beetles found upon grape- 

 vines likely to be mistaken for the grape root-worm are given, 

 and also a description of the character of the injury to the vine 

 wrought by the insect and the extent of its destructiveness. 



The technical descriptions of the different ages of the insect are 

 followed by a presentation of life-history studies involving many 

 careful experiments with numerous individuals. These studies were 

 undertaken to determine the length of the stages and the time at 

 which the different changes occur. This work was conducted for 

 three consecutive years with a view to determine the effect, in the 

 development of the insect, of seasonal variations due to varying 

 climatic conditions, and it has been productive of very interesting 

 results which have an important bearing on the time of application 

 of remedies. Soil conditions and altitude of vineyards are also con- 

 sidered in this same relation. 



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