Notes. 295 



The Irrigated Wheat Soils of Zeerust. 



At the request ui tlie Marion Agricultural and vStockbreeders' 

 Society, Mr. Hall, the Research Chemist at the School of Agriculture 

 and Experiment Station, Potchefstroom, went to Zeerust towards the 

 end of 1920 to investigate the diminishing yields of the wheat lands 

 from the standpoint of soil fertility. The result of th(> investigation 

 lias now been published in Bulletin No. 5, 1922, " Some Transvaal 

 Soils."* The three nmin soil types investigated were : (1) A red loam, 

 (2) a grey, highly calcareous loam (" as-grond "), and (o) a dark 

 brown to black calcareous clay loam (black turf). 



The red loam which changed from a sandy and stoney loam to a 

 clay loam, showed tlie worst nitrification of the three types. It was 

 also the poorest in organic inatter, water holding capacity and total 

 nitrogen. Like the other types it also was deficient in phosphates. 

 There was, however, sufficiency of lime and potash. The grey, highly 

 calcareous loam (" as-grond ") is a striking soil comjjosed of 50 to 

 96 per cent, carbonate of lime. It is easily worked, has a good water- 

 holding capacity, and is economical of water. It is well sui)i)licd 

 with nitrogen and potash, but deficient in phosphates. A coni];lete 

 fertilizer experiment with potatoes on this soil type was also carried 

 out. The experiment shows strikingly the value of phosphate witli 

 manure for potato production. The black t\irf is well supplied in 

 organic matter and lime, but is very deficient in phosphates and 

 l)otash. All these soils show fairly good nitrifying powers, especially 

 the grey calcareous loam, which even in the third foot samples showed 

 good nitrification. These soils liave been cropped continuously jor the 

 last 60 years, and to-day. despite heavy dressings of farju manure, 

 produce wheat which gives a good yield of straw, but little grain. 



The addition of k'raal and stable manure to soils well supplied 

 with nitrogen and potash but deficient in phosphates, is ajjf to pro- 

 duce crops of this nature, as the manure is most tieficient in the same 

 ingredient that the ;;oil lacks, viz., phosphates. Farmers are advised 

 not to discontinue the use of manure, but to reinforce it with phos- 

 phates. The use of 200 lb. per acre per annum of superphosphate is 

 advocated. 



The bulletin also refers to the satisfying results obtained by a 

 Zeerust fariror, who followed Mr. Hall's advice. Farmers are advised 

 also where nr.iiitire is unobtainable ic. grow summer legumes, and to 

 try potash as well as ]ihos])hates on the black turf soil along the 

 watercourses. 



Soils of the Eastern Tra-nsvaal Low Veld. 



The same bulletin (No. 5, 1922) refeircd to above, contains an 

 account of Mr. Hall's soil investigations in the Eastern Transvaal 

 low veld. This part of tlie country is being rapidly taken up by a 

 fine type of settler, and many inquiries concerning the needs of the 

 soils and the fertilization of semi-tropical crops are received. Last 

 year Mr. Hall spent seveial weeks in the Barberton district holding 

 meetings, visiting farms and studying the main soil types, which 

 appear to be chiefly of granitic origin and mainly (a) a grey, coarse, 

 sandy loam, and (h) a red loam, which changes in some i)hases to a 

 sandv loam, and in others to a (da\ev loam. 



* Obtainal)le on application to this oftiee. Price ;-id. prepaid. 



