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need protection from insect enemies and fungous diseases 

 the following year, in order to store sufficient energy to 

 produce a large crop the next season. The early leaf feed- 

 ers, such as the bud moth, the two case-bearers and canker 

 worms should be kept in check by annual sprayings. Un- 

 fruitfulness, in a measure, may be due to unsuspected 

 injuries by any one of these insects. The production of 

 large crops of high quality fruit necessitates vigorous trees 

 practically free from insect pests and fungous diseases, a 

 condition which can be brought about only by thorough and 

 systematic spraying. 



THE PRESIDENT. We will now welcome all the 

 questions you wish to ask. 



MR. E. M. IVES OF CONNECTICUT. The Doctor has 

 alluded to Black Leaf 40, which perhaps some of us are not 

 using. There has been trouble in combining Black Leaf 40 

 with arsenate of lead, and also in using Bordeaux mixture, 

 if you should use it in that first spraying before the petals 

 open. What suggestions has the Doctor on any experiments 

 that he has made along the line of using another combination 

 with Black Leaf 40 as an insect spray, and also as a fungi- 

 cide ? In other words, a combination of sulphide of iron and 

 zinc arsenate with Black Leaf 40. Have you made any ex- 

 periments with those combinations? This combination 

 spraying is something we have got to get right, and we have 

 evidently got to hit all these different things with the one 

 spraying, and this problem of summer spraying is a pretty 

 serious one ; and just where to hit, and hit right and combine 

 right, is a very intricate problem. 



DR. FELT. I don't know that I can answer you very 

 definitely, except to say that so far as Black Leaf 40 was con- 

 cerned, I understood that it could be used safely with a lime- 

 sulfur wash not with Bordeaux mixture, and that some other 

 tobacco preparations have given trouble. I do not wish to 

 be misconstrued as trying to defend one product more than 

 another, but I have alluded to this one because it seemed to 

 be a moderately standardized material, and the great diffi- 

 culty in the past in recommending a tobacco product has 

 been to get hold of something which you could refer to 

 definitely as containing so much of the actual insecticide. 



