44 



Journal of Agricultural Research 



Vol. XX, No. i 



whether the combination of the two conditions would induce a typical 

 chlorosis. It was thought that this might be determined experimentally 

 by growing rice on soil to which sodium bicarbonate had been added to 

 render it alkaline and then inducing an increased assimilation of lime by 

 spraving the plants with calcium chlorid and gypsum" In case these 

 treatments should induce a chlorosis identical with that produced by 

 carbonate of lime, spraying with ferrous sulphate should cure it. Accord- 

 ingly, some plants grown in the soil with sodium bicarbonate were 

 sprayed with lime salts alone, with ferrous sulphate alone, and with both 

 lime and iron salts. Plants grown in a soil without sodium bicarbonate 

 were also sprayed as described above in order to check the results. 



The experiment was carried out twice, once in the open, using small 

 brick compartments, and once in the glass house, using pots. Results 

 are given under the heads of experiments V and VI. The sodium bicar- 

 bonate was added in several doses until it became evident that sufficient 

 had been applied to affect growth. More was required for the soil in 

 the open than for that in the glass house, since the former was exposed 

 to leaching. 



Experiment V. — This test was run from November 8, 1913, to Jan- 

 uary 20, 1914. Each plot containing 150 pounds of sandy soil received 

 45 gm. sulphate of ammonia, 30 gm. acid phosphate, and 18 gm. muriate 

 of potash. Thirty rice plants were grown on each plot. The results 

 are given in Table VII. 



Table VII. — Effect of sodium bicarbonate, lime, and iron on Ike growth of rice: 



Experiment V 



Test 

 No. 



Ap- 

 proxi- 

 mate 

 percent- 

 age of 

 sodium 

 bicar- 

 bonate 

 in soil. 



O. 2 

 . 2 



Treatment. 



None 



Sprayed 31 times with 0.5 to 2 per cent solutions 

 of calcium chlorid and gypsum 



Sprayed 31 times with 0.5 to 2 per cent solutions 

 of calcium chlorid and gypsum and 8 times 

 with 0.5 to 1 per cent solutions of ferrous sul- 

 phate 



None 



Sprayed 31 times with 0.5 to 2 per cent solutions 

 of calcium chlorid and gypsum 



Sprayed 31 times with 0.5 to 2 per cent solutions 

 of calcium chlorid and gypsum and 8 times 

 with 0.5 to 1 per cent solutions of ferrous sul- 

 phate 



Sprayed 8 times with 0.5 to 1 per cent solutions 

 of ferrous sulphate. .. . 



" 



Air-dried weight of 

 plants per plot. 



Series 

 A. 



Gm. 

 144 



142 



163 

 IOO 



Series 

 B. 



Gm. 

 156 



152 



166 

 104 



82 



"3 



Aver- 

 age. 



Gm. 



ISO 



147 



165 

 102 



92 



105 

 "3 



