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found. For a number of years the pest has been troublesome in Ohio 

 vineyards, and also more or less locally in the Erie grape belt and in 

 New York State. In 1902, according to Slingerland, it was destruc- 

 tive all through the Chautauqua grape belt, and was equally destruc- 

 tive through a large part of this area during the two succeeding years. 

 At the present time the insect is destructive in individual vineyards 

 here and there throughout the Chautauqua, Erie, and northern Ohio 

 grape districts, causing a loss of many thousands of dollars annually. 

 In some vineyards a loss of from 25 to 50 per cent of the crop is not 

 infrequent, and in occasional instances the destruction of the fruit is 

 practically complete. 



Description and Life History. 



The grape berry moth is small, the wings expanding not quite one- 

 half inch. The general color is purplish brown, the wings with mark- 

 ings as shown in figure 2. Moths appear in the spring from hibernating 

 pupae, beginning about the time the shoots of the grape are pushing 

 out, and continuing to emerge for some weeks. The earlier-appearing 

 individuals deposit their eggs on the blossom clusters, while those com- 

 ing out after the blossoms are shed oviposit on the clusters of young 

 grapes. 



The minute scalelike eggs of the first brood of moths are difficult 

 to find, as at this time they are relatively scarce, but may be readily 

 detected during summer as a glistening or whitish spot on the surface 

 of the berries. The larvae of the first generation feed upon the blos- 

 soms and small berries, webbing them together more or less and 

 producing a more or less ragged bunch of grapes, or the cluster may 

 be almost entirely destroyed. The capabilities of the larvae for injury 

 at this time are thus seen to be much greater than is the case with 

 larvi^ of the later broods, by which individual berries are attacked. 

 The spring brood, however, is usually quite small; evidently there is 

 a heavy mortality of the insect during the preceding fall and winter. 

 About 3 weeks are required for a larva to complete its growth in 

 summer, when it is about three-eighths of an inch in length, slender, 

 light greenish to purplish in color, the head slightly bilobed, greenish 

 above, and brownish in front, the thoracic feet blackish. When 

 ready to pupate the larvae go to the leaves, and a small portion is cut 

 loose, except along one side, and bent over and fastened down with 

 silk. Beneath this a thin, whitish, silken cocoon is spun, and in 3 

 to 4 days the larva changes to a light greenish brown pupa, from 

 which the moth will emerge in some 12 to 14 days. The larva 

 and curious cocoon and pupa are shown in figure 2, considerably 

 enlarged. Moths of the second and later generations deposit their 

 eggs on the developing grape berries, and the resulting larvae bore 

 into these, feeding on the pulp and seeds, the entrance point of the 

 berry being marked by a purplish spot, which renders their detection 

 quite easy. In the Chautauqua and Erie grape belts, and probably 

 in northern Ohio, moths of the second generation will begin coming 

 out and ovipositing about the first week or ten days of July, continu- 

 ing for some weeks, the first and second broods overlapping. By 

 this time the insects will have increased greatly in numbers, and the 

 larvae will be attacking almost exclusively the berries of the grape, 



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