476 MINNESOTA STATE HORTICULTURAL SOCIETY. 



spray conveniently, and in such places a dust spray would be very 

 convenient and very beneficial, provided we can do as good work 

 with it as with a liquid spray. 



Prof. Green: I never experimented much with dust spray, but 

 this summer I carried on a considerable experiment to test the value 

 of dust spray as compared with liquid spray in applying it to potato 

 vines, and I got the best results from liquid spray. That experiment 

 is in bulletin form and should be out the beginning of the year. It 

 gives results of the treatment of potato vines for blight by applying 

 Bordeaux mixture, and we have obtained most excellent results. For 

 preventing the work of the potato bug I have had as good results 

 with the dust spray as with anything I have ever used. We used 

 air slaked lime and Paris green, and I like it better than anything I 

 have ever used for potato bugs. I do not like gypsum. A cheap 

 grade of flour is better yet. 



Mr. Yahnke : Where do you get your lime ? 



Prof. Green : I always prepare it myself. 



Mr. Yahnke: I believe that is where the mistake is made that 

 the gentleman I referred to spoke of, we do not make good dust. 

 He said he used the best lime obtainable and slaked it himself and 

 was very careful not to burn it. I am speaking now of Bordeaux 

 mixture. He said that was the principal reason why so many failed. 

 I am only telling you now what the gentleman told me, I am not 

 speaking of my own knowledge. 



Mr. H. J. Baldwin : I wonder if any one has ever found trouble 

 from Paris green poisoning the men who applied it. I had one man 

 pretty nearly killed. He said the poisonous dust got into his system. 



Prof. Washburn : If one gets a great deal of Paris green in the 

 lungs it will do some injury. 



Prof. Green : I was one of two boys who applied Paris green and 

 lime on twenty acres of potatoes when I worked for Gregory, the 

 seedsman. It was put on in dust form, and it did not hurt me, and 

 it did not hurt the other fellow, and it seemed to me as though we 

 were at it all summer. Anyway, I am still alive. 



Prof. Washburn : It does good work with the potato bug. It 

 kills the bug, but does not injure the vine. If you use arsenate of 

 lead you will find it better than Paris green. 



Prof. Green : The advantage with me has been that it was 

 necessary to send out only one man to put it on. We had to send 

 out two with the liquid spray. It is an advantage to take out a bag 

 of flour and mix it yourself. 



Mr. Yahnke : What proportion of flour do you use ? 



Prof. Green : About i lb. of Paris green to 35 lbs. of flour. 



Prof. Washburn : I think you can use i lb. to 50 of flour. 



Prof. Green : I use i lb. to 100 of air slaked lime. 



Mr. C. W. Spickerman: How do you use it? 



Prof. Green : With a bag of cheese cloth and a little box. 



