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ing of the Experiment IStatioa section and convey the resolution of this association 

 to meet with them at 4. Carried. The association then adjourned until 2.30. 



AFTERNOON SESSION. 



The meeting was called to order at 2.50. 



Mr. Cook offered the following resolution : 



''Resolved, That a committee be appointed to act in connection with the Associa- 

 tion of Agricultural Colleges and Experiment Stations." 



After some discussion the resolution was adopted. 



Mr. Howard moved that a committee of three, with the president as chairman, 

 should be appointed to report to the section of Experiment Stations at 4, and also to 

 attend the discussion of amendments to the constitution of the general association in 

 order to explain the status of the Association of Official Economic Entomologists. 



The topic, " How far shall we recommend patent insecticides and machinery," was 

 announced for discussion. Messrs. Cook, Lugger, Bruuer, Forbes, Riley, and Lintner 

 discussed this topic at some length, the joint opinion being embodied in the follow- 

 ing resolutiouj which was offered by Mr. Cook and adopted by the association : 



"Resolved, That in our opinion we, as officers of the Experiment Stations, should be 

 slow to recommend even by mention any patent insecticide until by analysis and test 

 we find it worthy of recommendation." 



The general opinion seemed to be that in case a patent insecticide proved to be 

 thoroughly efficacious and sufficiently cheap there should be no hesitation in recom- 

 mending it. 



Mr. Gillette read a paper entitled "Spraying Points," in which he gave certain 

 conclusions which he seemed to have reached by recent experiment. He stated that 

 white arsenic freshly mixed with cold water did less damage to foliage than Paris 

 green, while Loudon purple brought about greater damage than Paris green. Ar- 

 senic, however, prepared by boiling, produced a more injurious effect than either of the 

 other substances, which would indicate that it is the arsenic in solution that is to be 

 feared. 



Mr. Marlatt called attention to the fact that the different sides of the same tree, 

 according to sun exposure, and difference in the ages of trees, tend to produce different 

 results from spraying. The matter was discussed at some length by Messrs. Riley, 

 Lintner, Cook, and Gillette. 



Mr. Gillette read a paper entitled " Codling Moth Experiments," in which he gave 

 the results reached at the Iowa Experiment Station the jiast season by using a dry ap- 

 plication of Paris green in plaster, in the proportion of 1 of the poison to lUO of the 

 plaster ; an application of carbolized plaster prepared by thoroughly mixing 1 pint 

 of the crude acid in 100 pounds of plaster, and an application of London purple in 

 water in the proportion of 1 pound of the poison to 128 gallons of water. By esti- 

 mating the protection in the usual manner it was found that the Paris green and 

 plaster application saved 94 percent., the carbolized plaster 34 i^er cent., and the 

 London purple 68 per cent, of the fruit that would have been wormy in the absence oi 

 any treatment. 



Mr. Gillette then called attention to the fact that nothing like correct results could 

 be expected by figuring out the protection in the ordinary manner except in northern 

 latitudes where the insect is single brooded. The results obtained would be too small. 

 In order to get accurate results the two broods must be kept separate, otherwise the 

 results will be greatly vitiated by the great number of eggs that will be laid upon 

 the sprayed trees by moths flying in from the checks and also by the smaller number 

 of eggs that will be laid on the checks because of the great number of larv* of the 

 first brood cftestroyed upon the treated trees in their vicinity.* 



* This paper will appear in Bulletin No. 7 of the Iowa Agricultural Experiment 

 Station. 



