76 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 12 



condition. In southern California we used cottonseed oil soap, that is 

 the first boiling. 



The human nature of this whole problem from the farmer's stand- 

 point is the fact that if he can avoid actually having to mix something,, 

 weigh something or measure something, he is going to get out of it 

 regardless of a lot of other factors. Tell a man to cook something that 

 may take only five minutes of his time and if he can get out of that by 

 doing something easier, even if the other thing may not be as effective^ 

 it is human nature for him to do the other thing. You and I do it. 

 We can all shine our own shoes, but generally we get somebody else tO' 

 do it, and pay for the work. 



I have sometimes wished that somebody would write an article on 

 commercial recommendations and their bearing on biological recom- 

 mendations. I think that, perhaps, would solve the problem. Very 

 often in the laboratory something will happen that out in the field will 

 not, and I think the difference of opinion regarding dilutions comes un- 

 der that heading. In other words, a certain nicotine content will kill 

 the pest, say, aphis, if that aphis is thoroughly covered with it. Now^ 

 then, it becomes a problem, whether to be more thorough in your work 

 or try to cover up the sins of negligence by increased strength. I mean 

 the sins of negligence on the part of the grower. 



I wish some of those that have had experience within the past year 

 would tell the grower to do the work thoroughly or try to cover it up by 

 using a stronger dilution. I understand that in actual tests Professor 

 Headlee found that a dilution of Black Leaf 40 of one to eight hundred 

 would kill aphis in the laboratorj^ It seems to be thoroughness versus 

 strength and you and I as thinking men are going to differ on some 

 items. Here is a chance for each man to decide what he is going to do, 

 to choose thoroughness or by increased strength to hide the lack of it. 



In additional discussion of the soap problem: it has generally been 

 understood that arsenates and soaps should not be mixed. The reason 

 is that in some places many of us have actually seen cases of injury. 

 Now it is the one case of injury that establishes the rule; it is not the- 

 thousand cases of no injury. 



The more recent development I know only from conversation with 

 several entomologists, — and that is, that such a combination is now 

 considered safe. That is all I know about it. It is on good authority. 

 It may be that the arsenates have been standardized better than they 

 were before. But up to fifteen months ago the status was that though 

 there is only one chance in a hundred that there will be any injury fol- 

 lowing such a combination, because of that one chance, we have al- 

 ways been advised not to use it. However, that is superseded by the- 

 later announcement that arsenates and soaps can be mixed. 



