120 Bulletin 223. 



to such packing or sorting spots. Care should be taken to collect 

 and bury or burn all such "trimmings" from the grape clusters. 

 It will repay the slight extra expense many times over. 



Destroying sumac and other supposed food-plants. — That part of a 

 vineyard nearest woodlands, or perhaps a lot of sumac, is oftentimes 

 more infested by the grape-berry moth. And as the insect was sup- 

 posed to breed in sumac seed-bunches and on various other plants, 

 some have considered the destruction of such plants a helpful reme- 

 dial measure. But we have shown in discussing the food-plants of 

 this insect, that it now seems quite probable that it feeds exclusively 

 on grapes. Undoubtedly a large clump of sumac or other plants, 

 or an old brush-grown fence, near a vineyard, would afford a conveni- 

 ent place for a pile of grape leaves to accumulate, and thus might 

 afford the insect better hibernating quarters. The removal of such 

 useless plants or unsightly fences near vineyards is always advisable, 

 but it may help but little in reducing the numbers of the grape-berry 

 moth. 



Poison sprays are effective. — About nine years ago, the use of a 

 poison spray was suggested for combating this insect.* It was said 

 to be practicable only against the first brood, which was supposed to 

 develop on the green parts of the vine, and here the results would be 

 doubtful, for the insect was more than likely to breed on a great 

 variety of foUage, and thus spraying would not afford much protec- 

 tion. By 1898, however, the vineyardists of northern Ohio, who were 

 then fighting the grape root-worm, had found that they were control- 

 ling the grape-berry moth by spraying with poisons early in the 

 season, soon after the grapes had set, when the first brood of cater- 

 pillars work on the outside. f 



The vineyardists in Chautauqua county who co-operated with us 

 in the experiments in picking off and destroying the infested green 

 berries in August, also sprayed infested parts of their vineyards in 

 1903, and during the past season with the arsenate of lead. In one 

 case the poison was applied at the rate of 10 and 12 pounds in 100 

 gallons of water, the first appHcation being made just before the 

 blossoms opened, a second appHcation just after the petals of the 

 blossoms fell, and a third when the berries were about the size of 

 small peas. The vineyardist reported that these applications gave 

 almost absolute protection from the insect during the rest of the 

 season. Another grower who sprayed a little later this season with 

 "Disparene" at the rate of eight pounds in 90 gallons of Bordeaux 



* Marlatt in Yearbook of the U. S. Dept. of Agriculture for 1895, p. 404. 

 t Webster in Rept. Ohio Hort. Soc, for 1898, p. 3. 



