32 



FLAX CULTURE AND PREPARATION 



that can be readily absorbed by the growing plants. Such 

 fertilizers are usually classified, nitrogenous, phosphatic, and 

 potassic. 



Nitrate of soda a Chili deposit contains over 90 per cent, 

 of sodium nitrate. Pure nitrate contains from 15 to 16 per 

 cent, of nitrogen and is a highly soluble substance which is 

 frequently used as a top dressing for growing crops and after 

 dung and potassic manures. 



Phosphatic and potassic manures are chiefly derived from 

 bones, dried blood and other animal fertilizers. Their action 

 is slow, but when dissolved with sulphuric acid, they are 

 reduced into a more active condition and are more readily 

 absorbed by the plants. Bones thus dissolved are denominated 

 acid superphosphates. 



Basic Slag, containing 15 to 18 per cent, of phosphoric acid 

 and 50 to 60 per cent, of lime, is most suitable for sour and 

 peaty soils and those deficient in lime or rich in organic matter. 



Seaweed contains large quantities of lime and small 

 quantities of potash and phosphoric acid. 



31. Properties of Artificial Manures. The additional artifi- 

 cial manures and some of their properties will be found useful 

 classified as follows in terms per cent. 



A flax crop is usually grown without any added manure. 

 Many flax growers of long experience and considerable repute 

 have declared that they never manure the land when preparing 

 it for a crop of flax ; their arguments re same are chiefly 



