92 THE GRAPE ROOT- WORM. 



There is little danger that young vines will become reinfested dur- 

 ing the first season, since there is a very limited amount of cane or 

 stem upon which the beetle can deposit its eggs. By the second sum- 

 mer, however, the area upon which eggs may be deposited is somewhat 

 increased, and we have discovered occasional egg clusters of this insect 

 under the loose bark of the short stem of 1 -year-planted vines and 

 have also found a few larvae at their roots late in summer, indicating 

 that permanent infestation may take place early in the life of the vine- 

 yard. Hence it may be necessary to spray some vineyards from the 

 time of planting. 



Generally it is during the third season's growth of the vines, when 

 the cane is trained to the trellis, that serious permanent infestation, 

 by means of egg deposition by the beetle, takes place. The larvae, 

 hatching from these eggs are especially injurious to these young vines, 

 which possess but a limited root system compared with that of an old- 

 established producing vine. It is the opinion of the writers that the 

 first year or two of fruit production of young vines exposed to infesta- 

 tion is the most critical period of their existence, and especial care 

 should be taken during that period to prevent infestation by the 

 beetles. This can be accomplished by following the suggestions made 

 on pages 89-90, giving directions for the destruction of the beetles. 



When vines in a producing vineyard have been badly injured by 

 this pest, such vines may frequently be renovated by cutting them 

 back to the ground, so that the limited vitality of the injured vine 

 may be devoted entirely to the making of vegetative growth. A 

 heavy application of fertilizer should be made, consisting either of 

 barnyard manure or a commercial fertilizer containing a high per- 

 centage of nitrogen. The vines should be thoroughly sprayed at the 

 time the beetles make their appearance and thorough cultivation of 

 the soil should be maintained throughout the season. The grapevine 

 possesses remarkable recuperative power and, as the results tabulated 

 in this paper, under the heading of field experiments, indicate, 

 responds bounteously to careful and generous treatment. 



