58 FERTILITY AND FERTILIZER HINTS 



Nitrate of Soda. — This is a white or yellow or pink crystalline 

 salt. The nitrogen in nitrate of soda is in a form that can be 

 used by plants without undergoing any change. Nitrate of soda 

 is the highest in point of availability of any of the nitrogenous 

 fertilizer materials. It induces roots to grow deep. The ni- 

 trate diffuses into the subsoil and the plants send down their roots 

 for it. This is indeed of great benefit because it enables the plant 

 to better stand dry spells and it increases the area of plant food 

 supply. 



It is found in extensive deposits on the west coast of Chile 

 and is often called Chile saltpeter. The entire deposits are found 

 in layers sometimes 6 feet thick, about 2 to 10 feet below the 

 surface, and are blasted out and treated to rid the product of 

 impurities.* 



Composition and Properties. — Nitrate of soda contains 15 to 

 16 per cent, nitrogen and the average product found on the 

 American market contains 15.3 per cent, nitrogen. It is very 

 soluble in water and therefore it should be supplied in small 

 quantities frequently to prevent losing it by leaching. It should 

 be kept in dry storage as it absorbs water and is liable to liquefy 

 It is hard to distribute evenly on the soil unless it is mixed with 

 earth or some other material. On account of its caustic action 

 it should be applied around the plants and not on them as it 

 spots green vegetation. It should be kept away from live-stock 

 as it is poisonous. Acid phosphates when damp should not be 

 mixed with nitrate of soda as nitrogen is lost. The acid attacks 

 the nitrate of soda liberating the nitrogen.* 



The utilization of nitrogen from the air by artificially uniting 

 and fixing it with other elements to form compounds that could 

 compete with the other nitrogenous fertilizer materials has at- 

 tracted the attention of chemists and investigators for many years. 

 It seems that at last the problem has been solved and it is now 

 only a matter of a short time when the present modes of manu- 

 facturing artificial nitrogen compounds will be so perfected that 

 we will not be forced to worry about the future supply of this 

 important element. There are two of these artificial nitrogenous 



