EXPERIMENT STATION REPORT. 593 



somewhat ragged and mottled compared with those that had not 

 been treated. The only other difference was that on most of the 

 sprayed trees the foliage was thinner, indicating injury caused by 

 the applications. 



There were scales on the older leaves of almost all the trees, 

 and large, plump scales on most of the new growth, both sprayed 

 and unsprayed. 



As between the treated trees, the foliage on group 200 to 249 

 (Potassium, sulphide and lime) was a little thinner than normal, 

 a little ragged, and sojnewhat mottled. The foliage on group 

 250 to 301 (Sodium sulphite and lime) was a little ragged, but 

 otherwise nearly normal. The foliage on group 302 to 355 

 ("Con-Sol" .1 to 50) was somewhat mottled and showed a little 

 scalding. The foliage on group 356 to 2,y6 (lime, soda and sul- 

 phur) was a little thin and ragged, but hardly apparent. The 

 foliage on group 377 to 390 ("Con-Sol", i to 40) was well 

 mottled and more ragged than on any of the other groups. 



In the order of apparent effectiveness as against the scale, the 

 materials ranked : Lime, Sulphur and Caustic Soda ; Potassium 

 Sulphide and Lime, with little to choose between them ; "Con. 

 Sol", I to 50; "Con. Sol", I to 40; Sulphide of Soda and Lime. 

 That the "Con. Sol.", i to 40, was apparently less effective than 

 the weaker mixture may be due, in part to the fact that the treat- 

 ment was made later, when the trees were more infested. 



August 1 6th, trees 250 to 301 (Sulphide of Soda and Lime) 

 were sprayed with "Con. Sol", i to 40, as were the test trees 3, 

 9, 12 and 13. Trees 391 to 463 were sprayed for the first time 

 with the same combination. 



September ist, the following instructions were prepared: 



1. Examine the trees as on the previous visit, to determine the relative 

 effectiveness of the mixtures used. 



2. Determine what trees need re-spraying and spray with the "Oon. 

 Sol.," 1 to 40. 



3. Examine the trees sprayed at the last visit and note the effect of the 

 work on the insects and on the trees. 



4. Are there any trees that could be safely allowed to go into the winter 

 without further treatment? 



The replies are as follows: 



1. The mixtures rank in effectiveness: 1, Potassium sulphide and lime; 

 2, "Con. Sol.," 1 to 50; 3, and nearly equal to 2, lime, sulphur and caustic 

 soda; 4, sulphite of soda and lime, resprayed with "Con. Sol.," 1 to 40; 



