INDIANA HORTICULTURAL SOCIETY. 313 



sent one man to look over an orchard and sent another without letting 

 the second one know the first one had gone, and neither found any. We 

 have orchards we have not been able to find a scale in since we have 

 treated theru, and where they were badly infested before, and in no case; 

 have we found theTeffect to have been less than the extermination of nine- 

 ty-five per cent, of the scale destroyed. That is what we have done 

 with whale oil soap spray, with experienced men, who were doing the 

 very best that they could, 



Now, what we have done anybody else can do with the same equipm9nt 

 and thoroughly well trained men. In all the work we have done we have 

 used something like twenty tons of whale oil soap, and there has not 

 been a single complaint of any injury to vegetation. The most serious 

 complaint I had was from a lady, I don't know her age, and I do not 

 know whether she was married or not; but she complained that we ruined 

 her poodle by its getting out and getting sprayed. So I can say this much 

 about whale oil soap, that you, yourself, can put it on so that it will be 

 effective, if you know how, or have experienced men to do it. I have 

 told you of its efliciency, and there is one more point I wish to make,, and 

 that is that it will not protect a tree from reinfestation, I do not believe, 

 twenty-four hours ; it offers no protection from reinfestation from adjoining 

 trees or adjoining orchards. 



I desire now to take up the matter of the use of crude petroleum. 1 

 have done some experimental work with it, and there has been careful 

 application of it m.ade by the owners of the orchards, and we are just get- 

 ting some material together that will mean a good deal when we get 

 through with the season. Crude petroleum acts very peculiar in its effect, 

 not only upon the scale, but upon the tree itseif. It is a very easy matter 

 to spray a tree and not hurt it any, and it is a very easy matter to kill 

 the scale, but when you come to combine the two you have got something 

 else; that is where the difiiculty comes. We find it has a very severe 

 effect upon the tree, and anything less than twenty per cent, of ' crude 

 petroleum is ineffective, and anything more than forty per cent, injures 

 the peach trees more or less seriously. We have killed peach trees by 

 using twenty-five per cent, of crude petroleum, and we have sometira s 

 not injured them with fifty per cent., but where the injury is done with 

 twenty-flve per cent, they were very thoroughly sprayed. 



You will be more apt to do inefficient work in windy weather; and you 

 can not do as good work in a high wind as you can with the soap mix- 

 ture. So far as I can see there is no difference in the effect, so far as 

 specific gravity is concerned. We use oil whose specific gravity is 4.3 or 

 44 and we use it down to 34, and I can not see that the trees killed with 

 oil whose specific gravity was 44, was any more than those sprayed with 

 oil whose specific gravity was 34. We have been hoping that there might 

 be a difference in favor of the heavy oil as regards reinfestation, but we 

 got very disappointing observations the other day by finding the young 



