REMEDIAL MEASUKES. 63 



from large vineyardists concerning the undesirability of suspending 

 horse hoeing until so late a date. In 1907 we saw many hundreds 

 of acres of vineyard in the condition shown in Plate V, figure 1, in 

 which cultivation had been suspended to await the development of 

 the pup 86. Under normal conditions this cultivation would have 

 been performed several weeks earlier, and since early and thorough 

 tillage is essential to good vineyard management, it is not well to 

 place entire reliance on this operation to control the pest. Never- 

 theless it is an operation that should be utilized whenever soil and 

 moisture conditions will permit, and these are most favorable in 

 sandy and gravelly soils and in seasons of moderate rainfall during 

 the month of June. The most beneficial results from this operation 

 are obtained by horse hoeing as deeply as possible without scraping 

 the roots, followed by thorough and deep hand hoeing around the 

 crown of the vine, at which point by far the greater number of pupse 

 are to be found. 



During this investigation we have never felt warranted in placing 

 entire dependence upon this method of destroying pupae to control 

 this pest, but have regarded it as a valuable supplementary aid 

 obtained by a slight modification of general vineyard practice at no 

 additional expense to the vineyardist and that other means must be 

 employed to destroy the beetles developing from pupse which escape 

 destruction by this method. Since we were unable to find vineyard- 

 ists with heavily infested vines who were willing to allow us to con- 

 duct an experiment covering several acres for several consecutive 

 se'asons, depending entirely on the destruction of pupae by cultivation, 

 it is impossible to present definite data as to the exact value of this 

 treatment. 



EFFECT OF POISON SPRAYS ON THE BEETLE IN THE FIELD. 



The use of poison sprays against the beetles of the grape root-worm 

 after they have emerged from the soil and commenced to feed upon 

 the foliage of grapevines has been recommended by many ento- 

 mologists since the insect has become of economic importance as a 

 vineyard pest. 



Extensive experiments with arsenicals were made by Webster in 

 Ohio in 1895, and also by Slingerland and Felt in Chautauqua County, 

 N. Y., in a number of field experiments conducted during the seasons 

 from 1902 to 1906. 



Although in many of these experiments the results obtained indi- 

 cated a considerable degree of benefit from the use of arsenical poi- 

 sons, especially in those made by Slingerland from 1904 to 1906, there 

 has always been an element of doubt as to the value of arsenical 

 sprays applied to the vines as a direct and rapid killing agent of the 

 beetles. The inference has been drawn by some experimenters that 



