10 THE GRAPE KOOT-WORM. 



Preceding the discussion of remedial measures a brief summary is 

 given of the conditions in vineyards in the Lake Erie Valley since 

 their invasion by the grape root-worm, dealing with the age and con- 

 dition of vines at the time of its advent, the increase in area of new 

 vineyards, the insect's comparative destructiveness to old and newly 

 planted vines, and the relative responsibility of the pest for the 

 fluctuations of crop yields during the past decade. 



Cultural methods are considered with special reference to the 

 destruction of pupae in the soil. 



In the presentation of the data dealing with poison sprays for the 

 destruction of the beetles, details of experiments are given, first, to 

 show the efficiency of arsenicals as a direct killing agent of the beetles 

 in confinement and also in the open field; second, to show the rela- 

 tive value of arsenate of lead and of arsenite of lime; and, third, 

 to show the cumulative value of poison-spray applications on large 

 vineyard areas, both in crop yield and in vigor of vines as a result 

 of three consecutive years of this treatment. 



Following this experimental data on poison sprays the details are 

 given of field demonstration experiments with two run-down vine- 

 yards, conducted for three consecutive seasons. One, an old vine- 

 yard of about 10 acres, the other a young vineyard of about 5 acres. 

 The condition of each of these vineyards at the time the experiment 

 was undertaken is described and the plan of treatment — covering 

 general vineyard practice, such as pruning back of badly injured 

 vines, fertilizing, cultivation, and spraying with arsenicals — is given, 

 accompanied by the collected data showing the results of this treat- 

 ment in lessening deposition of eggs by the grape root-worm beetles, 

 in the diminution of grape root-worm larvae in the soil about the 

 roots of the vine, in the increase in crop yield, and in the general 

 effect of this combined treatment upon the health and vigor of the 

 vines. 



The remaining pages contain a brief discussion of arsenicals as 

 stomach poisons against the grape root-worm beetles, the desirability 

 of combining them with a fungicide when spraying for this pest, 

 spraying methods and spraying machinery as related to vineyard 

 treatment, and recommendations as to time and manner of making 

 applications. 



HISTORY. 



The first record of the beetle, Fidia viticida, the adult of the grape 

 root-worm, as a pest of economic importance upon grapevines was 

 made by B. D. Walsh in 1866 in the Practical Entomologist (see 

 Bibliography), and it is also to him that we are indebted for the first 

 description of this species of the genus Fidia. Yet as far back as 

 1826 this insect appears in entomological literature under a variety 



