37<'> V. KOZAI, M. TOVONAGA AND M. XAGAOKA. 





Experi- 

 mcntnl 



Nitrogen in the ch-y 

 matter of the whole crop. 



Nitrogen 

 in 

 the 



IVlflTlfTfJI 



extractetl 

 from the soil 

 resp. soil and 



manure 



Grms. 





year. 



0^ 



Gnus 



manure. 

 Grms. 



T 11 in '1 Tl 1 1 T/^( I 

 ^ lllllilliiJL l^>- 



1889 



1-435 



3-84 



0 



3-47 





1S90 



1.078 



5.66 



0 



3-89 





1891 



I 130 



5.01 



0 



4.65 





1892 



I.IS2 



367 



0 



3-66 





1893 



'•450 



2.09 



0 



1.72 





1894 



0.989 



6.06 



0 



5-84 



W" illi/iiii" Hit i"r\< I'f^i 1 

 W illKHIL IliLIUj^CIl 



1889 



1.054 



7-54 



0 



7.17 



yy yy 



1S90 



093 7 



7-43 



0 



5.66 



> J J» 



1891 



0.S93 



6.39 



0 



6.03 



J) 



1892 



0 786 



5-09 



0 



4.78 



J J »» 



1893 



0.8S8 



5.32 



0 



4.96 





1S94 



0,852 



6.27 



0 



6.05 



V„- V '11 1 1 'IC It. liuiJlUlC 



1889 



1.096 



13-37 



9 18 



13.00 





1890 



0.943 



12.46 



9.18 



10.69 





1891 



1 .002 



"•93 



9.18 



11-57 





1892 



1,026 



9.69 



8-33 



9-39 





1893 



1 .049 



963 



8.33 



9-37 





1S94 



0 962 



10 10 



8.33 



9.88 



In considering these results, it must be noticed that our soil is 

 very rich in nitrogen, this forming as much as 0.49 ^ of the dry- 

 matter. The high percentage of this nutriment in the plants grown 

 on the unmanured plots clearly proves that the stock of nitrogen in 

 the soil could not to be reduced to the minimum by the successive 

 cultivation of rice during the six years, and that the deficiency of 

 the other nutriments does not cause a greater consumption of it. 

 The percentage of nitrogen in the plants grown on the plots sup- 

 plied with much phosphoric acid and potash but not with nitro- 

 gen was the lowest, since the stock of this nutriment, though pretty 

 large, was not sufficient to secure maximum production of organic 



