SOIL IMPROVEMENT 79 



Choose the commercial fertilizers best and cheapest for soil and 



crop 

 Nitrogen suppliers: 



Guano, nitrate of soda, ammonia salts, cotton-seed meal, dried 



blood and tankage, fish scraps, artificial nitrates 

 Phosphoric 'acid suppliers : 



Guano, bones, phosphate rock 

 Potash suppliers: 



Ashes, kainit, muriate and sulphate of potash * 



Calcium supplier: 



Lime 

 Testing and mixing fertilizers 



