1912] The Work of the Dominion Experimental Farms 23 



For our present purpose, therefore, I have selected from our work a 

 number of examples that may be considered typical of the whole and 

 illustrative of the results achieved in the various lines of investigation. 

 They are merely indicative; many others might be cited equally or 

 possibly more important to Canadian agriculture, if time permitted. 

 And I must present them in the briefest possible language. 



The Maintenance and Increase of Soil Fertility. 



This is a problem of fundamental importance, since a productive 

 soil must be considered a sine qua non whether general farming or one of 

 its specialised branches is to be pursued with profit. Our study of 

 Canadian soils has shown many points of difference between those 

 naturally poor and thpse naturally rich, between those which have been 

 exhausted by irrational and wasteful methods and those farmed accord- 

 ing to the dictates of common sense and the teachings of science. 



The richest soils in Canada are the black loams of the great north- 

 western plains, many of which have been shown to contain from 18,000 

 lbs. to 25,000 lbs. of nitrogen, from 4,000 lbs. to 6,000 lbs. of phosphoric 

 acid, and from 10,000 lbs. to 15,000 lbs. of potash, per acre, calculated 

 to a depth of i foot — amounts of these essential elements of plant food 

 far in excess of those ordinarily found in soils of the best quality. This 

 great fertility must, as far as possible, be conserved, maintained, if this 

 national heritage, this valuable asset, is to be handed on as it ought to be, 

 unimpaired for future generations. 



Many of our poorest lands are to be found in the East — the districts 

 first settled. These soils very probably never equalled in richness those 

 of the prairie provinces, but irrational methods have gradually but 

 surely impoverished them. Their fertility must be increased if farming 

 in these districts is to be placed on a profitable basis. 



What is the outstanding difference between these virgin soils of 

 high fertility, of great productiveness, and those worn, exhausted soils? 

 It is that the former are characterised by large percentages of semi- 

 decomposed organic matter (humus) and nitrogen, whereas the latter 

 show but meagre amounts of these constituents. 



Further, we find, save in the semi-arid districts of the far West, that 

 there is distinct relationship between the organic content and that of 

 the nitrogen, that methods which destroy the former reduce the latter, 

 and vice versa. The humus of the soil is Nature's storehouse for its reserve 

 nitrogen, slowly made available for crop use through the agency of bac- 

 terial life under favourable soil and climatic conditions. The important 

 functions of humus — physical, chemical and biological — are only begin- 



