Representative Transvaal Soils. 



725 



Manurial Experiments. — The following- results were obtained in 

 an experiment on Koedoespoort No. 299 witli potatoes in 1908 (1). 

 Sample No. 1154 was representative of the plots: — 



It will be noticed that in every case in which superphosphate was 

 applied an increase in saleable crop of about 2500 lb. was obtained. 

 It is unfortunate that there was no plot manured with superphosphate 

 alone. The indications are that all the increase on these plots was 

 due to the superjihosphate alone, and that the potash and nitrogenous 

 fertilizers applied had little or no effect. Otherwise it would be 

 curious if nitrate of soda, nitrate of potash, and sulphate of potash 

 had almost exactly the .same effect. It will also be noticed that the 

 application of ten tons per acre of stable manure did not give as 

 heavy a crop as the superphosphate mixtures. 



In an experiment on maize on the same farm during' 1910-1912 

 the results were (3): — 



First series : Mixed maize and velvet beans. 



