In fifteen to thirty years, if nothing is applied to the land, the 

 yield decreases greatly. The secret of success is to keep up the 

 fertility of the land by farm manures and phosphates. 



Kraal or stable manure is a cheap and excellent source of plant 

 food, as it contains nitrogen, phosphates, potash, and lime. In the 

 soil, however, the nitrogen and potash are in excess of the phosphates, 

 and this is unfortunately the case also in the farm manures. These, 

 therefore, give best results when reinforced with phosphates : 2(10 lb. of 

 superpliosphates to 2 tons of manure for an acre is a good mixture. In 

 areas of high rainfall more manure can be used. If too much manure 

 is used, it supplies too much nitrogen, producing very leafy plants, 

 which " burn up " in a drought, i.e. suffer from lack of moisture, 

 because they use more than an unmanured plant by reason of their 

 extra leaf growth. Phosphates alone as superphosphates or bone meal 

 or a mixture of the two do not cause a " burning up," but 

 develop good strong roots, which help the plant to withstand the 

 drought, and still produce grain. A mixture of 50 lb. of bone nieal 

 and 150 lb. of superphosphates is a good mixture per acre. 



The maize grower is not advised to buy complete fertilizers, but 

 rather to make use of phosphates and farm manures. Where he 

 cannot get farm manures, then " green manuring " should be 

 practised. This consists of ploughing under any green crop and allow- 

 ing it to decompose in the soil. In the drier maize areas it is better 

 to feed oft this crop, usually a legume, or cut it for hay. Then plant 

 the land with maize the next year, and give a 200-lb. dressing of 

 phosphate per acre. 



Another important subject is crop rotation. It has been proved 

 time and time again that it is very bad to grow the same crop year 

 after year on the same soil. A crop rotation lessens insect pests, and as 

 different plants feed at different depths it helps to bring up the 

 available or soluble plant foods from the various layers of the soil. 

 A crop rotation should always include a legume, and some of the 

 crops should get phosphates. A rotation suitable for high veld and 

 middle veld areas is teff', cowpeas, and maize. The phosphates are 

 applied only to the maize. The cowpeas and teff are cut for hay. 

 The cowpeas give a dry-land hay equal to lucerne hay in feeding 

 value. Any suitable summer crop maj- be substituted for teff. 



Lime is cheap, but it does not pay to apply it to mealies, as they 

 grow veil on sour soil. 



Unless the land is ploughed and harrowed well, and the crop 

 kept nice and clean, fertilizers will not help much. But if this is 

 done much better results and heavier cobs will result than where 

 phosphates and a little manure have not been used or where legumes 

 have not been planted in the rotation. 



