The Grape-Berry Moth. 121 



mixture reports very few "wormy" grapes. Dr. Felt also reports 

 50 per cent less fruit damaged by grape-berry moths where arsenate 

 of lead and also a poisoned Bordeaux mixture was applied in 1903 

 for the grape root-worm beetles shortly after blossoming and while 

 the fruit was not larger than a small pea.* 



The above evidence in favor of the effectiveness of a poison spray 

 for the grape-berry moth leads us to strongly advise its use in infested 

 vineyards. Probably any of the standard poison sprays will do 

 effective work, but we like the arsenate of lead best. With this 

 poison there is no danger of injuring any part of the vine; it sticks 

 on longer than other poison sprays; and we have demonstrated its 

 effectiveness against the grape root-worm beetles (Bull. 224) which 

 need to be fought about the same time as the grape-berry moth. 

 Thus with this poison spray, the vineyardist can hit two serious 

 insect enemies at the same time, and by combining the arsenate of 

 lead with Bordeaux mixture, a very effective blow can be dealt to rot 

 and other fungous troubles. 



The poison spray is effective only against the spring brood of 

 caterpillars working in the blossoms and recently-set fruit clusters, 

 where they must work on the outside, and can thus eat the poison. 

 Two applications are advised, at the rate of about four pounds of the 

 arsenate of lead or " Disparene " in 50 gallons of water or Bordeaux 

 mixture. Spray first just before the grape blossoms open in the 

 latter part of June; make a second application just after the petals 

 of the blossoms fall. Doubtless a third application of the poison 

 will pay when the berries are about the size of grape-seeds. Only 

 thorough work wdll pay in spraying vineyards. Aim to cover every 

 fruit cluster and all the foliage with the poison and Bordeaux, thus 

 hitting the grape-berry moth caterpillars and rot fungi on the clusters, 

 and the root-worm beetles and mildews on the leaves. 



European methods. — ^The closely allied grape-berry moth which infests Euro- 

 pean vineyards does not differ in its feeding habits from the American species, 

 so the same remedial measures should prove effective during the growing season. 

 Laborers in Europe are sometimes trained to carefully pick out or crush the 

 first brood of caterpillars working in the blossom clusters. This is practicable in 

 our country when very observant help is obtainable. Hand-picking of infested 

 green grapes later in the season is also much practiced in Europe. 



A spray of soft soap, alcohol, and benzine is strongly recommended in Europe 

 for hitting and killing the caterpillars in their webs among the blossoms in spring. 

 Others report good results with a 3 per cent soap solution. The former would 

 be too expensive a spray for American vineyards, and om* cheaper poison spray 

 is_also very effective against some of the other enemies at the same time. 



As the European insect hibernates in cocoons on the'trimks of the vines and 

 on the trellis posts, it is effectively combated by stripping off the loose bark in 



• *BuU. 72, N. Y. State Museum, p. 31 (1903). 



