246 CHAPTER XIV 



where 20 to 25 per cent, of the rainfall occurs during winter, 

 wheat is only fairly successfully grown on dry-lands. How- 

 ever, the area to wheat there is diminishing, summer crops, 

 chiefly maize, ta.king its place. In the south and south-eastern 

 coastal area, where nearlj' 40 per cent, of the rainfall falls in 

 winter, rust is very bad, and the crop is an uncertain one. 

 In fact this area is spoken of as the " Kust Belt." 



In the Karroo area, where the rainfall is below 15 inches, 

 wheat free from rust and of very good quality is grown 

 under irrigation schemes, i.e., permanent irrigation dams, 

 saaidam irrigation, and torrential flooding. 



Soils. — Wheat will do better than the other cereals on 

 heavy soils ; however, generally speaking, loams and clay loams 

 are the best. It requires the plant-food of the soil to be more 

 available than do maize or oats. If green manures or barn- 

 yard manures are used they must reach a more thorough state 

 of decomposition to produce a good effect on the wheat crop 

 than in the case of the former two crops. Moreover, since 

 wheat is very sensitive to soil conditions, it requires a more 

 thoroughly pulverised and compact seed-bed than maize, oats 

 or rye. It prefers a neutral soil, being less resistant to alkali 

 than barley, mangels, cotton or sorghums, and does not do so 

 well on acid soils as rye, potatoes, buckwheat, soybeans and 

 cowpeas. 



Fertilisers. — In most countries nitrogenous fertilisers 

 are the chief fertilisers applied to wheat. In South Africa the 

 application of nitrogenous fertilisers is not so urgently neces- 

 sary. In the south-west Cape area sodium nitrate or guano 

 are used with good results. Elsewhere this can be supplied 

 sufficiently by the use of leguminous green manures. 



Phosphatic fertilisers are needed on most soils in South 

 Africa, and if judiciously used will give profitable results, 

 especially where the land has received a green manure pre- 

 viously. Present prices are abnormally high and fertilisers 

 should be used with caution. 



Each of the applications given below will prove highly 

 beneficial to the crop : — 



300 lbs. bone meal, plus 100 lbs. of blood meal, if no 

 green-ma.nuring has taken place, or 



300 lbs. guano alone, or 



200 lbs. superphosphate, or 



200 lbs. to 300 lbs. basic slag, according to the acidity of 

 the soil. 



