INSECTS INJURIOUS TO THE GRAPE 



463 



resembling the appearance of injury by the black rot. The 

 berries decay from the work of the larvae and from the entrance 

 of fungous diseases. The insect occurs throughout the United 

 States, but has been particularly injurious in the Chautauqua, 

 N. Y., Erie, Pa., and Northern Ohio grape belts. So far as known 

 the grape is the only food-plant and the species is a native one, 

 though its habits are very similar 

 to a nearly related European 

 species. 



The adult is a little purplish- 

 brown moth, with wings expand- 

 ing not quite one-half inch, and 



FIG. 386. The work of the grape-berry moth; infested cluster and single 

 berry opened to show larva at work enlarged. (After Slingerland.) 



shaded with brownish markings as shown in Fig. 387. The 

 ground color is lilaceous or leaden-blue and the spots are dark 

 brown. 



Life History. The moths appear in the spring as the shoots 

 of the grape are pushing out, and continue to emerge for some 

 weeks. The earlier ones lay their eggs on the blossom clusters, 

 while the later ones deposit them on the young grapes. The 

 minute flat, scale-like eggs are stuck to the surface of the stems 

 or berries, and look like small glistening, whitish spots. The 

 little larvae hatching from them feed on the blossoms and small 

 berries, webbing the clusters together, and might do much more 

 damage than the later generations were it not that they are much 

 fewer in number, there being a great mortality of the insects over 

 winter. The larvse become full grown in about three weeks. 

 The mature larva is about three-eighths inch long, varying in 

 color from dark greenish to dark purplish, with a light-brown 



