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before we can judge of the requirements. It is my liope tliat some one may 

 take up and study «"irefully tliis question of the differentiation of the phos- 

 phoric acid in upland soils. We Icnow that tlie Germans have done a great amount 

 of work in tliat direction, particularly in connectit>n with the moor soils in 

 northern (Jermany, and I believe then> is a great opening for investigation in 

 that particular line in connection with our upland soils iu the United States. 

 I am ready to be disputed on this point, for perhaps our points of view are 

 not all alike. 



There is another line of investigation tliat I hope sonicluxly will take up. We 

 hear nuich about humic acid, uhuic acid, i-renic acid, and apocrenic acid, and 

 perhaps other acid sul)stances belonging in the same category. It seems to nie 

 somebody ought to take up the study of the organic constituents of soils and 

 give the subject an overhauling. To-day we are obliged iu some respects to 

 cite Mulder when discussing these matters. To be sure, something has been 

 done since his time, but there is apparently yet a great field for work, and I 

 hope there are some here who will take it up. It will do no harm if more than 

 one station undertakes it. I am not one of those who think it is unnecessary to 

 duplicate work. We all recall the case where two men working at the same 

 time in different parts of the country came to the conclusion that each had 

 fcmnd the si)ecitic organism which caused potato " scab," yet later it was found 

 that one was right and the other wrong. Duplication of work is not always 

 by any means a waste of labor. For this reason I hope that no one will hesi- 

 tate to atta<-k these problems because of fear that some one else may be working 

 on them. 



Another (inestiuii that should i)e stu(lit>d is I be following, viz: What is the 

 influence of the materials that we apply to the soil upon the character of the life 

 within itV ,Tust to give ycm an idea of what I have in mind I will say that two 

 or three years ago we had just money enough so that we could hire a man to do 

 a little bacteriological work in the sununer upon the soil of two plats at our 

 station where sulphate of auunonia had been api)lied. One had been limed and 

 the other not. Some plants do not grow as well aTter liming as before, while 

 most varieties of plants grow splendidly where the lime has been applied. 

 Now, it struck me as a splendid plan to inoculate from both the limed and 

 unlimed soil upon both acid and alkaline media ; and as a result we found that 

 when the inoculating material was taken from the luilimed soil many more 

 forms appeared on the acid than on the alkaline media. When jnoculating 

 from the limed soil the reverse was true. In other words, it appeared that the 

 question of whether the lime was there or not had probably exerted a great 

 effect on the amount and kind of both the bacteria and fungi. And I wondered 

 what influence the greater amounts of these organisms and the particular kinds 

 might have upon the growth of agricultural plants. I had hoped at that time 

 that we might get the money from some source to determine these organisms 

 and to study their action and their infhience upon succeeding crops, both upon 

 the limed and unlimed soil. It seems to me that there are many opportunities 

 of this kind upon every experimental farm to study in regard to the influence of 

 specific maniu'es or soil amendments upon the life of the fungi and bacteria of 

 the soil. We have heard much recently concerning soil bacteria and the 

 importance of their study, and it has occurred to me that if they are as 

 important as is sometimes claimed, there ought to be an advantage, aside from 

 symbiotic action in legumes, in inoculating old soils which have been lying 

 neglected for years and to which nothing has been applied in the shape of stable 

 or other manures. One trial of this kind was made last year at our own sta- 

 tion, but without result. One lot of neglected soil was inoculated from a good 

 garden soil, and to the other the same amount of sterilized material from the 



