WATER SOILS. 829 



taken from tbe thousands of square miles of uncultivated soil in the 

 Dominion, they do not afford sufficient basis for generalizations regard- 

 ing the average soil fertility of the yet untilled areas of the respective 

 provinces." 



" Our data indicate that good agricultural soils in Canada possess usually between 

 0.25 per cent and 0.5 per cent potash; less than 0.15 per cent in our experience, points 

 to the necessity, or at all events to the value of potassic fertilizers, though with 

 good climatic and soil conditions the limit might be reduced to that suggested by 

 Hilgard. 



" The phosphoric acid in Canadian virgin soils of average fertility lies usually 

 between 0.15 and 0.25 per cent. Some good soils contain from 0.25 to 0.3 per cent, 

 and a few exceed the latter figure. The adequacy or otherwise of phosphoric acid in a 

 soil would appear to depend largely on the accompanying amount of lime. Increased 

 crop production has usually followed the application of phosphatic fertilizers to soils 

 containing less than 0.15 per cent phosphoric acid. 



" Lime ranks next in importance to potash and phosphoric acid in a consideration 

 of the mineral constituents of plant food. Our experience goes to show that clay 

 soils, containing less than 0.5 per cent will have their productiveness increased hy 

 a dressing of lime in one or other of its agricultural forms. Peaty soils and soils 

 generally that are rich in organic matter, are frequently poor in this element. All 

 such have been found to respond to an application of lime, and more particularly so 

 when given in conjunction with potash and phosphoric acid. For these classes of 

 soils, therefore, I deem it advantageous that they should contain at least 1 per cent 

 of lime. 



" Richness in nitrogen may be measured to alarge degree by the organic or humus 

 coutent, though the condition or stage of decomposition of this organic matter is an 

 important factor in determining the nitrogen's availability. The larger number of 

 our good soils contain between 0.1 and 0.2 per cent, though many reach 0.5 per cent 

 and some exceed 1 per cent nitrogen." 



Some investigations on the nitrogenous matter of the soil, 

 A. Pagnotjl (Ann. Set. Agron., 1898, II, No. 1, pp. 97-112). — Previous 

 work by the author is briefly summarized, and an account is given of G 

 series of pot experiments carried out during 1897. The general plan 

 of these experiments was as follows: Nitrogen in 3 forms — nitric, 

 nitrous, and ammoniacal — was determined in the soil at the beginning 

 of the experiment (200 gm. lots being used), various nitrogenous mate- 

 rials were added, and at intervals during periods of from 80 to IIS days 

 determinations of nitrogen in the above forms were again made. 



In the first series a comparison was made between the changes which 

 the organic nitrogen of the soil and that introduced in the form of dried 

 blood aud manure undergoes. In these experiments 7.4 per cent of the 

 original nitrogen in the soil, 59 per cent of the nitrogen of the dried 

 blood, and 48 per cent of the nitrogen of the manure was rendered sol- 

 uble in 80 days, due principally to nitrification. Over 50 per cent of 

 the nitrogen of the dried blood became soluble in 12 days. 



In the second series of experiments the assimilability of nitrogen in 

 ground meat, peanut cake, and sesame cake was compared. Sixty-two 

 per cent of the nitrogen in the meat powder was rendered soluble in 13 

 days, 100 per cent in 116 days; 64 per cent of the nitrogen of the pea- 

 nut cake became soluble in 13 days, 100 per cent in 116 days; and 62 



