April. "09] JOURNAL OP ECONOMIC ENTOMOLOGY 137 



2. Method of Spraying. — Further experiments have but confirmed 

 our previous assertion that in New England a drenching spray, as ad- 

 vised by some western entomologists, is of no value as far as driving 

 the spray into the calyx is concerned. The reason is not far to seek 

 if the apples are studied. Professor Slingerland^ has recently shown 

 that the calyces of apples may be closed before the stamen bars are 

 sufficiently shrivelled to allow the spray to penetrate to the lower 

 calyx cavity. ]\Iany careful examinations of Baldwin apples have 

 shown this to be absolutely true of that variety under our climate. 

 All of our experiments have been made on the Baldwin, as it is prac- 

 tically the only commercial variety in Northern New England. Our 

 heavy spraying was done this year with Bordeaux nozzles at an angle, 

 at 100 to 120 lbs. pressure, with a gas sprayer, and yet we were unable 

 to find the slightest of spray in the lower calyx cup. 



Where the calyx lobes remain open long enough to permit spray- 

 ing between them after the stamen bars commence to shrivel, there 

 can be no doubt that it is the desirable time to spray and that the spray 

 should be shot into the lower calyx cavity, but that such a spraying is 

 so all-efficient as recently claimed seems hardly to be demonstrated 

 by the evidence submitted. There are also striking differences in 

 the methods used to reach the lower calyx cavity by the chief advo- 

 cates of its use. In his first publication^ Ball tells us that a barrel 

 pump giving 85 pounds pressure enabled him to place the poison in the 

 lower calyx, and later' he states that a pressure of 85 to 120 pounds is 

 correct. But Melander* insists that 150 to 200 pounds pressure is 

 necessary and scouts the idea that satisfactory work can be done with 

 85 pounds pressure, referring to the work of Doyd in Illinois.'' 



The value of driving the spray into the lower cahrK cup was first 

 suggested by Ball in 1904. In Bulletin 95 of the Utah Station he de- 

 scribes the method used and in the summary states : 



' ' To get the best results from early sprays they must be applied in 

 the form of fine drops driven with force straight into the bottom of 

 the calyx cups." No experiments are recorded, however, in which 

 this method is compared with an ordinary mist spray thoroughly ap- 

 plied. Nor has he later described any experiments to prove the su- 

 perior value of such a method of spraying. The value of such spray- 

 ing seems to be based on the belief that most of the young larvee are 



"Journal of Economic Entomolog.v. 1 :352. 

 •Bulletin .95. Utah Agr. Exp. Sta. 

 'Bulletin 67. Bureau of Entomology, p. 63. 

 'Popular Bulletins. 5. Wash. Agr. Exp. Sta., p. 

 'Bulletin 114. 111. Agr. Exp. Sta. 



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