137 



fcults since we have been using the tobacco decoctions. 



MR. BRONSON : What is the weakest strength of lime- 

 sulfur for summer spraying that will prevent the germina- 

 tion of apple scab or kill it after germination ' 



PROF. FARLEY: I couldn't tell you. 



JMR. BRONSON: In other words, we have recommended 

 to us the use of 1 to 40, and a large number of our reports 

 say that burning takes place when used at that strength in 

 eastern Massachusetts for the control of apple scab. "Will 1 

 to 80, for example, be strong enough to prevent germination 

 or kill a very large percentage of the scab spores after they 

 have germinated? 



PROF. FARLEY: I doubt if 1 to 80 wcnild be strong 

 enough. 



MR. BRONSON: So that spraying with 1 to 80 would 

 be so much time and material thrown aAvay? 



PROF. FARLEY: Oh. no; it wouldn't be time and ma- 

 terial thrown away. It would give partial control, Init I 

 doubt if it Avould prevent the germination of the scab 

 spores, in all conditions of development. It might control 

 them to a limited extent, but the cntrol would not be thro- 

 cugh. 



MR. BRONSON: I would like to ask if the college has 

 had reports on that burning,-ahd' whJat the effect of the 1 to 

 40 is as to burning? 



THE PRESIDENT: We have had a great deal of com- 

 plaint that the combination of lime-sulfur and arsenate of 

 lead is troubling the eastern end of the State. I don't know 

 that we have had any reports about 1 to 40 or 1 to 50 alone, 

 but when they get the combination, particularly when thev 

 put in as much arsenate of lead as they have to do in thu 

 eastern part of the State for the gypsy moth, then you do get 

 trouble. I think ^Ir. ]\lann can tell us about that. 



]\IR. MANN: I have always seen trouble when we had 

 that strength of lime-sulfur. Any strength of arsenate we 

 would use would be 5 to 8 pounds to 50 gallons. 



THE PRESIDENT: At Amherst we use 1 to 50; that 



