^7° 



MAIZE 



CHAP, after the application of the mixed fertilizer was nearly double 

 • that obtained with the use of superphosphate alone. The 

 total increase was more than i \\ muids per acre in two years, 

 and the net value of the increase due to the use of the mixture 

 was £2 1 6s. 3d. per acre, as against 5s. 4d. per acre gained by 

 the use of superphosphate alone (Watt, R. D., 2). 



The conflicting results obtained with nitrate of soda at 

 Koedoespoort and at Potchefstroom emphasize the fact already 

 alluded to, that different soils require different manures to 



Fig. 127. — Effect of superphosphate and nitrate of soda mixed. 



produce the same crop. They also point to the necessity for 

 extended manurial experiments in different parts of South 

 Africa. 



337. Manganese Compounds. — Experiments conducted in 

 Japan and Italy, and at Woburn, Gronigen, and Uitenhage 

 (Sutkerst, 1 j, have shown that manganese has a beneficial effect 

 on certain crops and especially on maize. Large amounts of 

 manganese salts are injurious to crops, and the manganic salts 

 much more injurious than the manganous, but small amounts 

 (50 to 60 lbs. per acre) are found to improve the crops. 



