No. 6. DEPARTMENT OF AGRICULTURE. 587 



The female deposits the eggs under the loose bark of the vines, 

 usually upon the canes of the previous years' growth. The larvae 

 hatching from these eggs drop to the ground, enter the soil, and 

 feed upon the roots of the vine. It is upon the roots of the vine 

 that this insect does the greatest damage. Unfortunately, however, 

 no i)ractical means have as yet been devised for the destruction of 

 the larvae in the soil. Our investigations indicate that many of the 

 pupae can be destroyed by stirring the soil about the vines. By far 

 the most effective results were obtained, however, by the application 

 of a poison spray consisting of three pounds of arsenate of lead to 

 50 gallons of Bordeaux mixture. The Boideaux m.ixture is not 

 applied as an insecticide but for black rot and other fungus diseases 

 of the grape vine. 



Many acres of vineyards were treated in the course of this in- 

 vestigation and vineyards which had been reduced to a condition 

 of unprofitable crop yield were brought up to a state of profitable 

 production by the control of this pest in the manner just mentioned. 

 The results of this investigation of the gi'ape-root-worm are em- 

 bodied in Bulletin 89, of the Bureau of Entomology, Department of 

 Agriculture, Washington, D. C. 



Other insects in addition to the gi ape-root-worm were found in- 

 festing the vineyards, notably at this time the grape-berry-moth. 

 Polychrosis viteana. This insect is destructive in the larval stage 

 to the fruit and produces what the vineyardist knows as "wormy" 

 grapes. 



Injury by this pest is not general throughout the vineyards of 

 Erie county, nor is it uniformly destructive even in individual vine- 

 yards. Frequently, only a few vines on the ends of rows or, a few 

 rows along one side of a vineyard will be badly infested. The in- 

 festation becoming lighter toward the centre of the block while 

 the opposite side of the vineyard may be almost entirely free of the 

 pest. 



The adult of this pest is a moth similar in appearance to the 

 codling moth, but much smaller. These moths commence to emerge 

 in spring just previous to the blossoming of the grape and deposit 

 eggs on the unopened blossom clusters. The larva hatching from 

 these eggs feed upon the opening blossoms and small berries, spin- 

 ning a silken thread as they travel over the cluster, thus binding to- 

 gether the petals and stamens in a weblike mass which furnishes a 

 retreat and shelter for the ''worm." Where this early infestation 

 is heavy these webs are readily observed. A study of the habits of 

 this insect has shown that probaldy less than 25 per cent, of the 

 first brood eggs are laid on the blossoms clusters since the emerg- 

 ence of the moth spreads over a long period during the spring. 

 After the blossoms have fallen from the clusters the eggs are de- 

 posited on the small berries and the hatching larva feeds upon them. 



While the berries are small a single worm may destroy several 

 of them. Sometimes a larva will attack the stem of the cluster and 

 boring into it will destroy a part of the cluster. Later, as the ber- 

 ries become larger the larva on hatching enters the berry and two 

 or three berries at most furnish sufficient food for its development. 

 When the larva is full grown it leaves the fruit and forms a pupa 

 case upon the leaves of the vine in which it transforms to the moth. 



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