42 



been able to spray their orchards with this substance without injury, 

 many others had not. The reason for this difference was not plain to 

 him, as in some cases, at least, there was reason to believe that the 

 men were equally careful. 



Mr. Webb stated that the results from spraying with the lime, 

 sulphur, and salt wash had varied widely in Delaware. In some cases 

 the results had been excellent. Five hundred 3-year-old trees in fair 

 condition, only moderately infested with the scale, had been thor- 

 oughly sprayed with this wash, so that they were white from top to 

 bottom. Shortly afterwards the trees had been examined very care- 

 fully by Professor Sanderson, who thought that not 25 per cent of the 

 insects had been killed; but in August and September there were but 

 very few living scales to be found. Mr. Webb stated that he had 

 examined the apple trees frequently himself, and was very soon struck 

 with the fact that no young scales could be found. On the other 

 hand, an orchard on the adjoining farm, a year or two older, sprayed 

 by the same men and under apparently similar conditions, showed 

 very poor results. At no time during the season were the trees at all 

 free from the young, crawling scales, and by the middle of the sum- 

 mer a great many of the trees had been ruined. On the whole, very 

 little benefit seems to have come from the treatment. Mr. Webb 

 thought there was undoubtedly an explanation of the difference in 

 results, but was not able to account for the difference himself. Mr. 

 Webb mentioned other cases where orchards of from 500 to 1,200 

 trees had been sprayed, though the work had not been done very 

 thoroughly, but he considered the results excellent in view of the fact 

 that the work had been done so poorly. Considerable crude oil and 

 some refined oil had been used in Delaware on peaches and plums as 

 well as on apples and pears, and there had been absolutel} T no injury, 

 unless, as mentioned by Mr. Alwood, the attempt had been made to 

 kill the trees. With some pumps, making a mechanical mixture of 

 oil and water, the mixing had not been well done, some trees showing 

 just a trace of oil and others were covered with a thick coat. Yet no 

 injury had resulted from such treatment, so that the majority of fruit 

 growers are rather inclined to use the oil. 



Good results had also been secured by the use of the soap emulsion, 

 which was used to a considerable extent, and, all things considered, 

 he thought probably this had given best results. The refined kerosene 

 had been used almost exclusively in making this soap emulsion, but 

 very little of the crude oil being used. In one instance, where 25 per 

 cent emulsion had been sprayed on plum trees just before the buds 

 had opened, there had been no injury, and a full crop of fruit had 

 been borne by the trees the following year. This same orchard had 

 been treated in the spring of 1902 with approximately 33 per cent of 

 kerosene emulsion with very excellent results, although the treatment 



