260 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 4 



cent of the scale were killed. The clump sprayed with 20 per cent 

 kerosene emulsion showed, on an average, about 75 per cent killed. 

 The clump sprayed with 30 per cent showed an average of about 90 

 per cent killed. None of the plants showed any injury whatsoever 

 from the application of the spray mixture. It was, therefore, deter- 

 mined to spray additional clumps. On July 29 seven additional clumps, 

 together with those originally sprayed, were sprayed with 30 per cent 

 kerosene emulsion. This was repeated on August 11. On both dates 

 the sun shone brightly all the time the spraying was going on and it 

 was exceptionally hot, even for that season of the year. These clumps 

 were examined on March 4 and it was found that about 95 per cent 

 of the scale were killed on the clumps which had received two spraying 

 with 30 per cent kerosene emulsion. The results were no better than 

 this on the clump which had received one spraying of 15 per cent 

 kerosene emulsion and two sprayings with 30 per cent kerosene emul- 

 sion. The clump which had received one spraying with 20 per cent 

 and two sprayings with 30 per cent showed about 98 per cent of the 

 scale killed. The clump which had received three sprajdngs with 30 

 per cent kerosene emulsion seemed to be j^ractically free from scale 

 and although it received no subsequent sprayings it remained free 

 from scale, and was one of the most beautiful clumps on the lawn when 

 last inspected on September 9, 1910. 



On March 4 a new series of experiments was started. Six sections 

 of the main part of the hedge, measuring about thirty feet each, were 

 sprayed with the following mixture: Commercial lime-sulphur, 1 to 10 

 and 1 to 15. Scalecide, 1 to 10 and 1 to 15. Kerosene emulsion, 

 40 per cent and 60 per cent oil. These sections were examined on 

 June 3, when it was found that none of the hedge had been injured 

 by any of the mixture. Arranged according to their relative effec- 

 tiveness they would rank about as follows: Scalecide, 1 to 10; kerosene 

 emulsion; 60 per cent, scalecide, 1 to 15; kerosene emulsion, 40 per 

 cent, Ume-sulphur, 1 to 10; Hme-sulphur 1 to 15. 



On June 3 additional sections of the hedge were sprayed. Half of 

 each of the blocks sprayed with scalecide on March 4 were sprayed 

 with scalecide, 1 to 35. In addition ninety feet, which had not been 

 previously sprayed, was gone over with scalecide 1 to 35 and sixty 

 feet with scalecide, 1 to 25. Half of each of the sections which had 

 been sprayed with lime-sulphur on March 4 were sprayed with lime- 

 sulphur, 1 to 30. In addition two blocks of 150 feet each were sprayed 

 with commercial Hme-sulphur at 1 to 20 and 1 to 30. Half of each of 

 the blocks which had been sprayed with kerosene emulsion on March 

 4 were sprayed with 30 per cent kerosene emulsion. In addition fifty 

 feet of the unsprayed portion was sprayed with 30 per cent kerosene 



