1905.] DISCUSSION. 139 



If he was a potato grower, however, he would not hesitate to 

 use this method of combating the fungus, believing that it 

 would pay in the long run. Spraying with the bordeaux mix- 

 ture should begin about the middle of July and at least three 

 applications of two to three barrels per acre should be given. 

 The second application might be given about the first of August 

 and the third after the middle of that month. One, however, 

 must use his judgment as to the exact time and the number 

 of applications, as these depend upon the weather. The proper 

 thing is to have the foliage well covered with the mixture 

 when the blight weather comes on. When needed, paris green 

 — one-half pound, to the barrel — may be added to the mix- 

 ture to fight the potato bug, and there is no danger of burning 

 the foliage. There is considerable work about spraying large 

 fields and it necessitates a convenient and good water supply. 

 The geared sprayers that pump out the mixture as the horse 

 carries the apparatus along are rather unsatisfactory for use 

 with bordeaux mixture, since they do not sufficiently drench all 

 parts of the foliage even when driven over the same rows a 

 second time from the opposite direction. A barrel pump car- 

 ried on a one-horse cart — one that can straddle two rows of 

 potatoes — with one man to pump and drive and two to follow 

 on foot, each with a sixteen to twenty-foot hose pxovided with 

 a single nozzle and spraying two or three rows as he goes, is 

 the most efficient way of spraying a field, but it takes time and 

 labor and lots of the mixture. 



: DISCUSSION. 



The Secretary. You will notice Dr. Clinton is the only 

 speaker on our programme who has ever spoken before at a 

 midwinter meeting. I happened to be at Dr. Clinton's labora- 

 tory in October and found he was at work upon a scientific 

 investigation of the diseases of the potato in Connecticut. I 

 thought it was too important a subject to be neglected, there- 

 fore he was asked to speak on this subject before you today. 

 There are two questions I would like to ask him. The first is 

 in regard to the selection of seed. If I understood him cor- 

 rectly he recommends selecting seeds from the plants before 



