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vicinit}' of Albany. X. Y.. the assertion quoted is too sweeping- in its 

 character. 



This spring' a series of tests were begun with the avowed purpose of 

 learning the best method of controlling the San Jose scale in orchards. 

 During the progress of this work trees were treated with mechanical 

 mixtures of water and kerosene and with crude petroleum in a similar 

 manner, using '20 and 25 per cent of the oils, which were applied Avith 

 a Gould's kero-water sprayer. A few trees were treated with undi- 

 luted kerosene and others with undiluted crude petroleum. A num- 

 ber of trees were treated with whale-oil soaps. Leggett's Anchor 

 brand and Good's caustic potash whale-oil soap No. 8 were each used 

 at the rate of 2i pounds to a gallon of water. A combination of 

 whale-oil soap and crude petroleum was also used on a number of 

 trees, the proportions being 1 pound of the soap to -i gallons of water 

 and to 10 gallons of the soap solution 1 gallon of crude petroleum. 

 A kero-water sprayer was on the ground and it was therefore easier to 

 prepare the soap solution and arrange the apparatus to deliver 10 per 

 cent of crude petroleum. This produced an emulsion as it passed 

 through the nozzle. In addition to these, 12 trees were treated with 

 hydrocyanic acid gas, using from 1 pound of the cyanide to To cubic 

 feet to 1 pound to 150 cubic feet of space. The spraying was mostl}^ 

 done on April 11. though the fumigation was delayed until the lUth 

 to 21st of April, at which time the buds had started some. This work 

 was performed in a mixed orchard of over 100 young pear, peach, plum, 

 and cherry trees, where the San Jose scale had been for about eight 

 3^ears, and the trees presented, therefore, every degree of infestation. 

 Unfortunateh% it was necessary to confine the use of the undiluted ker- 

 osene and crude petroleum to the worst infested trees. It is yet early 

 to pass upon the etfectiveness of these substances as insecticides and, 

 therefore, only the effects on the trees will be considered at this time. 



The spraying with the insecticides occurred just before the buds 

 began to open, and with the exception of the trees treated with undi- 

 luted kerosene or crude petroleum very few or no harmful effects 

 were observed. Examination of the experimental orchard eight days 

 after spraying, showed that as a rule the trees were budding out. 

 Those treated with kerosene gave little indication of the presence of 

 the oil on the bark, while the dark color of those treated with crude 

 petroleum Avas very apparent, a condition Avhich persisted till June 20 

 at least. The whale-oil soaps showed to a considerable extent, the 

 bark of the trees treated Avith Good's l)eing moist, while many of those 

 sprayed Avith Leggett's shoAved a white incrustation. The harmless- 

 ness of a mechanical 20 per cent kerosene emulsion applied at this 

 time is well shown in the cherry tree No. 8, photographed MaA' 12 

 while in full bloom. Tree 15, a Seckel pear, photographed May 11, 

 shows Avell the harmlessness of a mechanical 2o per cent crude petro- 



