52 



Table VII. — The Effect of Nitrogenous Fertilizers on 



the Development of Soluble Manganese, and on 



Plant Growth. -Early Planted Crops Only. 



NO-^ Mn., and Green Weights of 



Sorghum in Grams. 



^\pparently there was an error in this determination. 

 "One pot omitted from average, since it was evidently abnor- 

 mal. 



The soil from plot 4 is a yellow rather hea^y one, 

 inclined to run together and puddle when wet. Ac- 

 cording to the Veitch method, the lime requirement 

 is about 4,000 pounds per acre. In this experiment 

 ammonium sulphate was nitrified but little in the un- 

 limed pot. However, the water soluble manganese re- 

 covered by leaching was nearly ten times as great as 

 from the unfertilized pot. Dried blood was nitrified to 

 some extent, and the soluble manganese recovered was 

 about seven times as great from the untreated pot. The 

 other soil used is of a rather coarse sandy nature and 

 leaches very readily. By the Veitch method, the un- 

 fertilized plot has a lime requirement of about 1200 

 pounds per acre. In this soil ammonium sulphate was 

 not nitrified; and seemed to retard nitrification in the 

 unlimed pots. On the other hand, dried blood was ni- 

 trified to a moderate degree, under the same condi- 

 tions. Both the ammonium sulphate and the dried 

 blood caused a very considerable increase in the solu- 

 ble manganese in the unlimed pots. 



Considering the plant growth, it will be seen that in 

 ])oth soils the addition of ammonium sulphate proved 

 highly detrimental to sorghum in the unlimed pots. 

 In fact, all tlie ])lants died soon after they came up. 

 Without lime, dried blood produced but very little bet- 

 ter growth than did the nntreated soil. From the limed 

 pots, only traces of manganese were recovered; and the 

 growth of sorghum in these was very satisfactory. The 



