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TWENTY-NINTH FRUIT-GROWERS' CONVENTION. 



toward better and more uniform distribution of the material at a less 

 cost than is usually the case. Time does not permit us to enter into 

 the detail of these experiments in this paper. They will appear in full 

 in the series of bulletins soon to be published by the Experiment 

 Station. 



All we will attempt now to say is that work with platforms built 

 upon the spray wagon which permits of an economical and thorough 

 distribution of the material from above has proved such an improve- 

 ment over the present methods in this State that it should lead to a 

 very general adoption of the method in the future, as is the practice in 

 many parts of the East. That the use of power outfits is in the long 

 run more economical and undoubtedly more satisfactory than that of 

 hand outfits in well-grown orchards we consider as also amply proven 

 in our experiments. 



As for the most satisfactory nozzle to use, our experiments seem to 

 indicate that early in the season a rather coarser spray is to be desired 

 than is the case later on in the year. A nozzle, therefore, that would 

 be satisfactory for the first two sprayings would have to be replaced by 

 one throwing a more finely divided and fog-like spray in subsequent 

 operations. This is a very complicated subject, however, and will be 

 thoroughly discussed in a bulletin about to be issued by the Experiment 

 Station. 



Arsenicals Used. — In the greater number of our spraying experiments 

 during the past season the arsenical poisons were used, and in no case 

 were satisfactory results obtained from the use of other materials, many 

 of which were experimented with. It will not be necessary to give 

 details of our work with these other materials in this paper. Of the 

 arsenicals, the paris green is the best known and was most extensively 

 used in these experiments. The reason for the very large use of this 

 arsenical is primarily the fact that it is easily obtained and its purity 

 or impurity can be readily determined by analysis under the law govern- 

 ing its sale in California. All of the paris green tested and used by us 

 this season was well below the limit of four per cent free arsenious oxid 

 allowed by this law, and its physical condition was,* generally speaking, 

 good. In our spraying experiments the paris green was always applied 

 in combination with lime, on account of the liability of burning the 

 leaves under those climatic conditions. The amount of lime used per 

 pound of the green varied on different orchards from four to twenty 

 pounds, and on all but one orchard the milk of lime, well strained, Avas 

 used. In the case of this one orchard clear lime water was used, and 

 while very satisfactory results were obtained such a method of procedure 

 can not be recommended until further experiments along the same line 

 have been made. At least fifty per cent of the orchards of Monterey 

 and Santa Cruz counties were sprayed with some combination of lime 



