22 BULLETIN 42, U. S. DEPARTMENT OF AGRICULTURE. 



EFFECT OF MANGANESE SULPHATE ON CORN. 



Six years' results have been secured with corn. The manganese 

 was applied in the spring of 1907, before the planting of corn. The 

 ground, as in the other test, was thoroughly prepared, and the crop 

 was cultivated throughout the growing season. Manganese sulphate 

 was applied each year at the rate of 50 pounds per acre. 



Table XIII gives the yields of stover and grain for the manganese 

 and the check plots. The first column gives the year of growth, the 

 second and third the yields for the manganese plot. The fourth and 

 fifth columns give the yields for the untreated plot. The results have 

 been calculated to pounds per acre of stover and bushels per acre of 

 shelled corn. In making the calculations from pounds per square 

 rod to bushels per acre, 56 pounds was taken as the weight of a bushel 

 of shelled corn. These results are given in columns 6, 7, 8, and 9. 

 The last two columns give the increase or decrease of stover and 

 grain per acre on the manganese plot. 



Table XIII. — Effect of manganese sulphate on corn grown on soil treated six successive 



years. 





Yield per square rod. 



Calculated yield per acre. 



Year. 



Manganese 

 sulphate. 



Untreated. 



Manganese 

 sulphate. 



Untreated. 



Increase or 



decrease of 



manganese plot. 





Stover. 



Grain. 



Stover. 



Grain. 



Stover. 



Grain. 



Stover. 



Grain. 



Stover. 



Grain. 



1907 



1908 



1909 



1910 



1911 



1912 



Pounds. 

 65 

 21 

 19 

 27 

 25 

 17 



Pounds. 

 14 



18 

 6 

 8 

 7 

 3 



Pounds. 

 57 

 26 

 27 

 39 

 30 

 34 



Pounds. 



21 



25 



7 



14 

 14 

 16 



Pounds. 

 10,400 

 3,360 

 3,040 

 4,320 

 4,000 

 2,720 



Bushels. 

 40 

 51 

 17 

 23 

 20 

 9 



Pounds. 

 9,120 

 4,160 

 4,320 

 6,240 

 4,800 

 5,440 



Bushels. 

 60 

 71 

 20 

 40 

 40 

 46 



Pounds. 

 +1,280 



- 800 

 -1,280 

 -1,920 



- 800 

 -2, 720 



Bushels. 

 -20 

 -20 

 - 3 

 -17 

 -20 

 -37 



The only increase from manganese noted was in 1907, when there 

 was an increase of 1,280 pounds of stover per acre. However, there 

 was a decrease in grain. The effect of the manganese sulphate was 

 to decrease the yield of both stover and grain in the following five 

 years. In 1907 the decrease in grain was 20 bushels per acre. In 

 1908 stover was decreased 800 pounds per acre and the grain 20 

 bushels per acre. In 1909 the stover was decreased 1,280 pounds 

 and the grain 3 bushels per acre. In 1910 the decrease of stover was 

 1,920 pounds and the grain 17 bushels. In 1911 the decrease of 

 stover was 800 pounds and the grain 20 bushels. In 1912 the de- 

 crease of stover was 2,720 pounds and the grain 37 bushels per acre. 



EFFECT OF MANGANESE SULPHATE ON COWPEAS. 



As with the corn plots, the manganese sulphate was applied to the 

 cowpea plots beginning in the spring of 1907. Six years' results have 

 been secured. Manganese sulphate was applied each year at the 

 rate of 50 pounds per acre before planting. 



