SO 



ference of percentage of potash in the stems from the two plats is 

 great, although the differences between the percentages of nitrogen, 

 and likewise of phosphoric acid, contained in the same parts of the 

 plants from the two plats, become very small towards maturity. It 

 must be borne in mind that in soy bean cake the amount of potash 

 is about 25 % of the quantity of nitrogen. Thus the rice plant 

 could have absorbed a much greater amount of potash from plat A 

 than from plat B, though the plants from the former plat gave a 

 little poorer yield of grain, (v. Table 34 and 15) It is clear from 

 Tables, 32, 33 and 34, that the actual amounts of nitrogen and of 

 phosphoric acid absorbed by the rice plants of these two plats are 

 about the same, but that potash is present in a greater quantity in 

 the entire plant that in grown on plat A- Therefore the potash 

 contained in the soy bean cake may influence the growth of the rice 

 plant, when the soil, as in this experiment, is fertilized at the rate 

 of 34.00 Ibs. of potash per acre ; however, the phosphoric acid, of 

 which there is only a small s mount in soy bean caks, does not exert 

 so much influence as potash, when 68.00 Ibs. of phosphoric acid per 

 acre is applied. 



It is very important, as regards fertilizer application, to know 

 that such a surplus amount af potash in the rice plant's body hind- 

 ers the proper growth of the craps. In the spring of 1915, another 

 experiment was carried out, with a view to ascertaining, (i), the 

 effects of potash fertilizer on the yield of rice and, (2), the potash 

 content in the plant's body at various stages of growth. The soil 

 selected for the experiment was in a nearly exhausted field, on which 

 rice crops had been cultivated eight times in succession, without any 

 fertilizer being applied. This soil showed a slight acidity when 

 treated with a solution of neutral salts. Each plat was fertilized 

 with ammonium sulphate, superphosphate and ^potassium carbonate, 

 containing respectively nitrogen, phosphoric acid and potash at the 

 following rates per acre : 



