252 



SCIENCE 



[N. S. Vol. XXXVIII. No. 973 



active occupancy of the scientific field and 

 because of the very vital problems with 

 ■which he deals, whereby each one of the 

 natural fields of science must depend upon 

 him for facts as to the construction of 

 matter, has always had a very strong influ- 

 ence upon the formation of all our theories 

 and principles of agriculture, and I think 

 I may not be open to too strong criticism 

 when I say that we have allowed the labo- 

 ratory chemist and the untrained middle- 

 man or field agriculturist who, in the past, 

 has taken his doctrines largely from the 

 assertions of the chemist, to lead us past 

 many of the problems in cereal cropping. 



In this matter of depleted soils and de- 

 teriorated cereal crops, it may be admitted 

 that there are depleted soils — soils too poor 

 to grow pay crops of any one of the cereals, 

 but they are not, in the belief of the writer, 

 located in any of the present great natural 

 wheat- or cereal-growing regions. The 

 great flat prairie lands of this country 

 which are now producing the so-called de- 

 teriorated types, black-pointed, white-bel- 

 lied, piebald wheat with attendant low 

 yields per acre, are not comparable in the 

 difficulties of maintaining fertility with 

 the denuded water-washed hiUs of New 

 England, New Tork, Maryland or Vir- 

 ginia; nor should they be classed with 

 sewage-clogged lands as described by Rus- 

 sel and Hutchinson of the Rothamsted ex- 

 periments. "When I say this for the Amer- 

 ican natural wheat-producing areas, I may 

 say that I have investigated the problem 

 sufficiently to feel certain that the world- 

 wide problem is comparable to our fertile 

 land problem, is, in fact, in large part the 

 same problem. 



Soils may blow away, wash away, or 

 may be sewage-clogged, but these are not, 

 at present, the chief reasons for low yields 

 of wheat, oats and barley in certain nat- 

 urally very fertile lands of "Wisconsin, 



Iowa, Minnesota, the Dakotas and north- 

 west Canada, or indeed, of the old winter 

 wheat lands of southern Ohio or Indiana. 



That you may feel certain of where I 

 stand in the matter, I feel justified in as- 

 serting, from my studies and those of vari- 

 ous assistants who have been aiding me in 

 my investigations of problems of cereal 

 deterioration, that the chemists are now no 

 more nearly accurate in their diagnosis of 

 the chief wheat troubles in these and other 

 natural wheat-cropping areas than they 

 were a generation ago when the most ex- 

 pert among them insisted that the methods 

 of the chemical laboratory would allow 

 them to determine whether water is fit for 

 drinking or not. They could not then tell 

 whether water would or would not produce 

 disease and death. Neither can the chem- 

 ists in their laboratories determine the 

 probable productivity of a particular piece 

 of wheat soil. It seems clear, from the 

 investigations of many men, that chemical 

 analysis is no longer the yard-stick for the 

 measure of the productivity of a soil. 

 Rather must we say that the real measure 

 of the fertility of a soil is the crop which 

 it will produce under a given method of 

 procedure, tillage, drainage, rotation, etc. 



I would remind you that I am not talk- 

 ing against the use of fertility in the grow- 

 ing of crops. I know well the list of essen- 

 tial chemical elements that must be present 

 in a soil in certain reasonable proportions 

 in order that there may be a crop pro- 

 duced. I would remind you, however, that 

 this is not the problem under considera- 

 tion. The problem under consideration is : 

 "Why is it that fertile wheat lands do not 

 produce wheat of reasonably normal qual- 

 ity? Why is it that the yield per acre 

 diminishes rather than increases in spite of 

 present best methods of agriculture ? 



I again assert, the chemists are not more 

 able to tell by chemical analysis of a wheat 



