11 



work, covering 12 or 15 acres per day, using an insufficient amount of 

 spray. With the spraying machinery in common use 7 to 8 acres per 

 day is about all that may be covered with the desired thoroughness, 

 and about 125 gallons of spray mixture should be applied per acre. 

 In spraying for the grape root-worm, the poison should always be 

 applied in Bordeaux mixture, which is used in the control of fungous 

 diseases, as elsewhere considered in this bulletin. The several arsenical 

 poisons which may be used are discussed on pages 26 and 27. 



Destruction of beetles by jarring. — Doctor Felt has made extensive 

 practical tests of jarring the beetles from the vines and catching 

 them on sheets or special forms of catchers run under the plants or 

 along the rows, and considers this to be an effective plan of con- 

 trolling the pest, the jarring of the vines causing many of the 

 beetles to fall in their efforts to escape detection. A sheet of canvas 

 placed on the ground beneath the vines will serve to catch the beetles, 

 but where work of this kind is done on a large scale special apparatus 

 must be provided. There is room for considerable ingenuity in con- 

 structing catchers that will suit individual conditions. Concerning 

 the value of jarring. Doctor Felt says:'* "Our experience with col- 

 lectors has demonstrated the practicability of catching the beetles, 

 and we recommend this operation for all badly infested sections, and 

 that the collecting be begun as soon as the beetles appear on the vines 

 in any numbers, say where there are 12 or 15 on one. The operation 

 should then be repeated at intervals of 5 to 7 days till the vines have 

 been gone over two, three, or four times, depending somewhat on the 

 number of insects which are captured. It will be foimd that it is much 

 easier to catch the beetles on warm days, when it should be done, than 

 in cool weather." 



Destruction of pupae by cultivation. — "V^Qiile the grape root-worm 

 may be present in well cultivated vineyards, it is much less 

 destructive than in vineyards which receive indifferent cultivation or 

 total neglect. It has long been known that much good may be done 

 in controlling insects which live underground by breaking open their 

 pupal cells and crushing or otherwise killing the helpless pupae. 

 The importance of this work in the destruction of pupse of the grape 

 root-worm was first pointed out by Professor Slingerland in his 

 studies of this pest in the Chautauqua grape belt, and subsequent 

 experiments, confirmed by practical experience, have shown that this 

 is a very important method of reducing the numbers of insects. After 

 the larvae have become full grown the great majority pupate but 2 or 

 3 inches below the surface of the soil, and mostly within a radius of 

 IJ or 2 feet from the base of the vine. In this stage the insects are 

 quite helpless, and are killed in large numbers by a thorough breaking 

 up of the soil around the base of the plants. As stated, the insect will 

 be in the pupal stage in maximum numbers just before the period of 

 blooming of the vines, and the cultivating should be done at this time. 

 In the Ohio, Pennsylvania, and New York grape districts this will be 

 about the middle of June, the time varying somewhat according to the 

 character of the season and of the soil. The details of this work are 

 very important and require explanation. 



With the last cultivation in the fall the earth should be thrown to 

 the vines on each side, forming a ridge along the row. The following 



a Bui. 19, Office State Ent. of N. Y., p. 37 (1903). 

 284 



