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out injuring the trees. He made some tests with the kero-water pump 

 which were not very satisfactory — that is, the pump would not throw 

 a given percentage constantly — and in the experiments made recently 

 a motor-spray pump had been used. This pump was used largely in 

 the northern section of Ohio and very few trees were injured, but the 

 scale was not held in check. This year the trees were sprayed more 

 thoroughly. Some were over sprayed, and. as a result, at the present 

 time, he estimated that there were probably 10,000 dead trees in that 

 section. This is the principal fruit-growing district, and such a loss 

 means considerable to the growers. The men who applied the spray 

 in this section were growers who have had a great deal of experience 

 in spraying, and certainly would be as careful as hired men. Mr. 

 Burgess related one instance where peach trees were seriously injured 

 by using 25 per cent mechanical mixture of crude petroleum, and 

 called attention to a recent New York bulletin, in which it was stated, 

 from results there indicated, that peach trees sprayed late in the spring 

 were less liable to injury than if sprayed earlier in the season. His 

 experience in northern Ohio was almost opposite. The trees sprayed 

 late in the spring had been injured more than those sprayed earlier, as 

 in January or somewhat later. The fact that so many trees had been 

 killed and injured this year made the scale problem a serious one. 

 The growers were enthusiastic in using the crude petroleum and 

 thought they had found a substance which could be used safely to 

 kill the scale. It seems now that much more care will have to be 

 used in its application, or a safer remedy devised. A good many 

 growers last } T ear thought they had not sprayed sufficiently and this 

 year attempted to spray the trees more thoroughly. On peach trees, 

 a very careful application of crude oil must be made. Attention was 

 called to another point in this connection — that the effect of spraying 

 was different in different years. Some growers had sprayed thor- 

 oughly last year and no injury had resulted to their trees. The same 

 trees had been sprayed this year with considerable injury. The 

 results did not seem to show, one year with another, what results 

 might be expected after spraying. 



Mr. Quaintance remarked that according to his experience in Mary- 

 land there was considerable variation in the effect of both kerosene and 

 crude petroleum in different parts of the State. In western Maryland 

 the kerosene treatment, on the whole, had been found quite satisfac- 

 tory, and 20 per cent kerosene in mechanical mixture was very largely 

 used. On the Eastern Shore, however, the use of kerosene or crude 

 petroleum, even under the most favorable weather conditions, had 

 been reported in numerous cases as giving fatal results to the trees. 

 On the whole, for this territory he was inclined to recommend the use 

 of whale-oil soap. He stated that he had met with much difficulty in 

 the use of the kero-water pump, from the fact that the percentage of 



