CONTROL OF GRAPE-BERRY MOTH. 6 



vines and plowing three successive furrows of soil toward the 

 vines. Thus all leaves and trash in the vineyard are covered with 

 from 3 to 5 inches of soil and ideal winter protection is afforded 

 the hibernating pupae which are in cocoons in the old grape leaves 

 (PL II, fig. 2). In the spring before time for moth emergence this 

 soil is worked away from the vines. In the Sandusky region it is 

 plowed away and in grape sections near Cleveland it is removed 

 with a disk or worked away with a shovel cultivator. This cul- 

 tivation breaks the crust formed in the winter and in many cases 

 turns to the surface the pupa? (PL I, fig. 3) that were plowed under 

 the previous fall. This practice of covering the pupae for the winter 

 and then uncovering them early in the spring protects them from the 

 extreme winter and allows the moths to emerge in the spring. 



Pupae of the berry moth, kept in the insectary yard at Sandusky 

 under conditions similar to those described for the vineyards, lived 

 through the winters of 1916-17 and 1917-18. In the spring of 1917 

 the emergence was 20 per cent and in 1918, after an unusually severe 

 winter, it was 26 per cent. Comparative data are not at hand for 

 the same winters with pupae exposed as they would be in a vineyard 

 plowed before grape harvest and then left until spring. In experi- 

 mental work reported by Isely, 1 however, it was found that subsequent 

 emergence from cocoons left through the winter of 1915-16 

 under exposed conditions in the vineyard was but 5 per cent as com- 

 pared with 30 per cent emergence where the cocoons were covered 

 by 2 inches of earth and then uncovered before time for emergence 

 in the spring. 



Since late plowing away in the spring is objectionable in northern 

 Ohio from a horticultural standpoint, the writers recommend that 

 when cultivation is completed in July the vineyards, whenever pos- 

 sible, be placed in final cultural condition for the winter and then 

 that they be left in that condition until the next spring. The only 

 objection to this practice is the excessive growth of weeds, which in- 

 terferes with harvesting. This can be overcome by seeding a cover 

 crop at the completion of cultivation. 



METHOD OF HARVEST. 



A large part of all the grapes in these sections and practically 

 all of the Catawba variety were formerly sold for wine making. 

 Since no particular packing is required for this market, all sorting 

 is done in the. vineyards by the pickers. AYormy berries are cut or 

 shaken out of the clusters and allowed to fall to the ground and to 

 remain in the vineyard. It appears that any other method of dis- 

 posing of the infested grapes would be more costly in labor than 

 would be warranted now that satisfactory control may be secured 

 by spraying. 



1 Isely, Dwight, op. cit. 



