552 ANNUAL REPORT OF THE Off. Doc. 



PKOF. SURFACE.— Not to great extent. If I spray my trees I 

 do not believe it is possible to wipe it out entirely, but if we can 

 control it so as to produce first class fruit, in spite of its existence, 

 we shall be as successful in commercial fruit growing as though it 

 were exterminated. 



"It is better to spray orchards from one end to the other when 

 only a few trees are actually found infested, and thereby prevent 

 injury, rather than to delay the spraying until the orchards become 

 badly infested by the scale." 



Now I had hoped to give you at this time the results of our tests 

 of different commercial insecticides, but we have not quite finished 

 the study of the field notes on these, although they will be published 

 in our next monthly bulletin. These results, however, are so well 

 expressed in the New York bulletin, which I hold in my hand, that 

 I shall read it to you and give you my sentiments. This is from a 

 summary of a series of extensive experiments with commercial in- 

 secticides, published in Bulletin No. 281, of the Geneva, New York 

 State Experiment Station. It may be obtained free by writing for 

 it. Prof. Parrott, summarizes his experiments and I shall read you 

 less than a page of his conclusions. 



"This bulletin contains the details of a number of experiments 

 with commercial miscible oils to determine their merits for the con- 

 trol of the scale. This work was conducted in three orchards in 

 which 1,368 trees were sprayed with these preparations in various 

 proportions. On the basis of these tests the following conclusions 

 are drawn: 



"Applications of proprietary miscible oils at the rate of one part 

 of oil to twenty or twenty-five parts of water, fail to give uniform 

 results on scale. Trees receiving these treatments usually showed 

 more or less spotting of the fruit and varying infestation of the new 

 growth. 



"Miscible oils in the proportion of one part of oil to ten or fifteen 

 parts of water, while uniformly more destructive to the scale than 

 the weaker preparations, were usually not quite so efficient as the 

 boiled lime-sulphur wash. These stronger applications destroyed 

 large percentages of the scales, being sufficient effective to maintain 

 the thriftiness of the trees and to keep the fruit crop fairly clean. 

 On the basis of these results even the better ones of the miscible 

 oils tested should not be used in weaker mixtures than one part to 

 ten or fifteen parts of water. 



"The miscible oils are commercial insecticides and therefore the 

 orchardist should understand that the reliability of the stock 

 material rests with the compounder. These sprays are simple to 

 prepare for use, and are convenient preparations for the treatment 

 of old trees and small orchards." 



That is where I endorse them specially as they are easily prepared 

 and applied, if a person should not desire to make the homemade 

 insecticide for use in only small quantities. 



"The cost of the miscible oils in the proportions of one part to ten 

 or fifteen parts of water makes their use almost prohibitive for 

 commercial orchardists who desire a safe and comparatively cheap 

 oil spray. Compounds of commercial insecticides should endeavor 

 to produce a reliable miscible oil that i-s cheaper than present 

 brands." 



