THE MONTIITA' BULT.ETIN. 21 



Wilson in the Biennial Crop Pest and Horticultural Report, 1911 and 

 1912, of the Oregon Agricultural College Experiment Station, Cor- 

 vallis, Oregon, reported good results against the eggs of the purple 

 apple aphis and green apple aphis with Black Leaf 40, 1 to 900, and 

 Black Leaf 40, 1 to 900 combined with commercial Lime-Sulphur 1 to 

 10, but did not obtain good results from the use of Lime-Sulphur alone. 

 He also recommends a 15 per cent Kerosene Emulsion, but in each case 

 his recommendations were mainly against the stem mothers, and were 

 not true egg treatments. 



Davidson, Bulletin No. 100, LTnited States Department of Agri- 

 cultiire, reports success against the eggs of the walnut aphides with 

 connuercial Lime-Sulphur diluted 1 to 8 to 1 to 11; also, good work 

 from Crude Oil Emulsion 8 to 12 per cent, using the heavier grades of 

 oil, and from Yel-Ros (a miseible oil from a high gravity oil), 1 to 25. 



Entomologists from the eastern states disagree as to the efficiency 

 of controlling the apple aphides by a treatment for the eggs during the 

 dormant season, and the majority of them have had inferior results. 



Plan of Work. A number of Newtown Pippin trees from the 

 nursin-y fi-oui one to two years old were planted in a straight row in 

 the early spi-ing at distances of about five feet. As mentioned before, 

 these ti'ees were covered with the eggs of the green and ])urple apple 

 aphides, and majority being those of the former species. The appli- 

 cations were made February 28, 1914, a .Myers foot ]uimp being 

 used, and as much pressui'e obtained as was possible, care being exer- 

 cised to cover every tree thoroughly. 



Materials Used. It Avas planned to use various miseible oils and 

 homemade oil emulsions from high gravity oils extending down to 

 low gravity products; also, Lime-Sulphur solutions, nicotine com- 

 pounds, and all these by themselves and in combination with nicotine. 

 Unfortunately, no homemade Lime-Sulphur solution was • used and 

 none of the nicotine compounds were used by themselves on account 

 of their giving better spreading ([ualities and penetration when in 

 combination with a soap solution or a w^^ak oil ennilsion. The pro- 

 portions used for making oil ennilsions will vary somewhat, depending 

 upon the kind of soap aiul oil em])loyed. 



4—14911 



