520 ANNUAL, REPORT OF THE Off. Doc. 



HOME-MADE SOLUBLE OILS. 



By Pbof. H. a. Surface, Economic Zoologist, Harrisburg, Pa. 



Concermng this subject of Mr. Atkinson's orchard over near Am- 

 bler, I want to say that although he made the statement that the 

 lime and sulphur wash had failed to control the scale, I have hun- 

 dreds of letters from all over the State, saying that lime and sul- 

 phur is absolutely the best remedy to free trees from scale. After 

 he made that statement, I went to see him about it, and he practi- 

 cally gave me a conference during most of the afternoon, and he 

 finally said that he probably made his statement too strong; the 

 men who were sent out to spray his orchard did not do the work 

 properly; only one side of the tree was sprayed, and they really did 

 not spray at all, only put a little of the mixture on the trees. He 

 told me that while he considered his orchard had not been saved by 

 the one application of lime and sulphur wash, had he published what 

 he knew of the use of commercial oils, it would have been five times 

 worse, as his trees (especially pear) were at one time stunted and 

 absolutely permanently ruined by the use of oils. 



Now, I am to talk to you on the subject of ''Home-Made Soluble 

 Oils," but I am in a position where I can yet scarcely speak positively 

 on the subject from personal experience^ and don't wish to mislead 

 any one. There are two bulletins on this subject, one published in 

 Delaware, and one in Connecticut. The Experiment Station at 

 Storrs, Conn., published a bulletin on this, after experimenting in 

 this direction, but what I am going to say to you is based on our 

 experiments by one of my assistants, Mr. F. L. Hartzell, who has 

 experimented with the making and use of this material, and on what 

 I have learned by studying the subject. 



So far as we know now, many of the so-called "soluble oils" put on 

 the market under various high-sounding names can be made at 

 home at less than one-half the cost you can buy them in any case 

 oft'ered, and there is less of the danger element. The danger with 

 most of these commercial oils is that if they are strong enough to do 

 the work of killing the San Jos^ Scale they are liable to damage 

 the tree, and again, these oils are not fungicides. Then, again, there 

 is the high price. Now, some of the chemists and entomologists of 

 the different states decided to see whether they could not make a 

 soluble oil that would be cheaper and better, and between them the 

 following formula has been prepared. 



You make first the emulsifier. Oil treated with this emulsifier has 

 the advantage over the crude petroleum alone in that when we are 

 going to use it we can dilute it with w^ater to the amount we want 

 to put on the tree. First, let me state to my correspondents that I 

 am going to work this out myself, and publish it in my Bulletin, so 

 they need not take only my present word for it; now, this is the 

 emulsifier: 



