VI. Entomology. 75 



oils. The proprietary article, known as " Scalecide,'" was selected 

 for this test. One hundred and twenty gallons of it was purchased 

 for use in this orchard and in making a similar test on a smaller 

 scale in another section of the State. The infested orchard consisted 

 of 600 six-year-old pear trees, and two or three hundred large plum 

 and peach trees. Not all of the trees were infested with the scale, 

 but 200 or more or them were encrusted with it in many places. It 

 was decided to make the first application early in October before the 

 leaves were off. About half of the trees were sprayed at this time 

 with Scalecide, at the rate of one gallon of the oil in 125^ gallons 

 of water, after some prelimnary tests on a few trees with different 

 strengths of the material had been made. An examination a little 

 later showed that 90;^ or more of the scales had been killed, and 

 while some of the leaves were burned, apparently no injury had been 

 done to the fruit buds or bark. The whole orchard was again 

 sprayed in November after the leaves had dropped with the oil, 

 at the rate of one gallon in fifteen gallons of water. A third appli- 

 cation was made early in the spring before growth began with the 

 insecticide at the same strength as in the second application. The 

 work was most thoroughly done under the eye of the owner with 

 a gasoline engine sprayer, carrying a pressure of 125 pounds. The 

 orchard was watched with interest during the past summer, and it 

 was soon evident that most, if not all of the scales, had been killed. 

 So confident did the owner become that he finally offered one dollar 

 each for every living scale found upon the treated trees. I examined 

 the trees carefully two or three times during- the summer and in 

 September, and other entomologists and horticulturists did the same. 

 Although every effort was made to find living scales, the owner 

 reports that no one claimed any dollars. It is a curious and inter- 

 esting fact, that the scales all came off from the bark of the Japan 

 plum trees, whereas large numbers of the dead scales remained on 

 the pear trees during the season. These results are certainly remark- 

 able, carried on as they were as a business proposition, by a fruit- 

 grower himself. I fully realized that the experiment was in good 

 hands, and that my directions would be faithfully and thoroughly 

 carried out. The success of this experiment is due, I think, to the 

 thoroughness with which the material was applied, the pressure that 

 was used, and the number of applications. I believe it is practically 

 impossible to kill all the scales with one application of any insec- 

 ticide yet recommended for this pest, and I believe this is the 

 explanation of many of the reported unsatisfactory results for spray- 



