THE DEVELOPMENT OF SOLUBLE MAN- 

 GANESE IN ACID SOILS AS INFLU- 

 ENCED BY CERTAIN NITRO- 

 GENOUS FERTILIZERS/' 

 By 

 m. j. funchess 

 Associate Agronomist, Alabama Polytechnic Institute 



Introduction 



In the spring of 1913 a scries of plots on the Alabama 

 Experiment Station Farm was devoted to a field study 

 of the rate of nitrification of dried blood, cotton seed 

 meal, and calcium cyanamid. The amount of ferti- 

 lizer applied to the several plots was sufficient to sup- 

 ply seventy-seven pounds of nitrogen per acre. An 

 attempt was made to prevent leaching on small areas 

 of some of these plots by protecting them against rain- 

 fall with covers during the winter of 1915-1916. Dur- 

 ing the period, it was noticed that a brown crust had 

 accumulated under some of the covers on the fertilized 

 plots. Nitrate determinations made on this brown 

 soil crust showed a nitrate content as high as 4959 p. 

 p. m. of nitrates with an average of 2269 p. p. m. as the 

 result of six determinations. 



Soil taken from beneath these covers and used in a 

 pot experiment with corn in the green house, proved 

 to be less productive than unfertilized soil which con- 

 tained only a normal amount of nitrates. In a similar 

 experiment with sorghum as the plant indicator, the 

 plants made little growth and finalh' died oh the high 

 nitrate soil. On the other hand, pots to which lime 

 had been added made a vigorous growth and devel- 

 oped normally. The work suggested that this acid 

 soil, when carrjdng a high nitrate content, contained 

 some substance which was injurious to plants, and 

 that liming reduced or prevented the injury. 



An effort was made to determine the nature of the 

 basic material in the extract of this soil, but lack of 

 time prevented the completion of the work. Enough 

 progress was made, however, to show that the extract 



*The writer Iicreby expresses his appreciation of the faith- 

 ful and elVicitnt assistance rendered by S, A. Wini^ard and F. 

 W. Parker in tlie prosecution of the work here reported. 



