1907- ] DISCUSSION. 167 



Secretary Browx. That is one of the points that I would 

 like to know myself. The circular intimates that the firm pre- 

 paring this preparation propose to send a gentleman to show 

 the work. I did not know but Dr. Jenkins, or some one con- 

 nected with one of our Experiment Stations was familiar with 

 the subject, and that is why I brought it up. 



Mr. Platt. Mr. Chairman, I have not used sulphate of 

 iron for killing weeds, but I have used common salt. In the 

 case of Canada thistles, where they were almost extinct by 

 extreme cultivation, by following it up for two or three seasons 

 they can be cleared out. The salt will be better in such cases 

 as that. 



Mr. Phelps. So far as I know, I have not heard of any 

 experience with sulphate of iron used in the way that the Sec- 

 retary referred to, but in some places they have recommended 

 for use sulphate of copper for spraying on to grain in order 

 to kill mustard. Some plants are much more susceptible to 

 that kind of a product than others, and it has been demon- 

 strated, I think, that the mustard plant is one of that variety, 

 and can be killed by spraying upon the foliage a weak solution 

 of sulphate of copper. In England they are more thorough 

 in their methods with regard to grain growing than we are 

 in this country perhaps. They have to spray quite extensively 

 with sulphate of copper for the destruction of mustard and 

 thistles. 



The President. It won't hurt the grain? 



Mr. Phelps. No. The grain is not injured at all if they 

 use the right strength. 



The Secretary suggested a while ago that the speaker of 

 the afternoon was rather late, and if there is time I would like 

 to refer to the subject which was up this afternoon. It may 

 not be one that is w^orth killing time over, but it may be one 

 worthy of a little further exemplification, and that is the 

 question of securing chemicals, and mixing fertilizers upon our 

 farms. That is a question of considerable importance, espe- 

 cially to those who use these mixtures in considerable quanti- 

 ties. For about eight years I have been buying from fifteen 



