Pkoceedings of Seventeenth Normal Institute 12.J 



Cyanamid is us(3d very extensively in commercial fertilizers, 

 some three hundred fertilizer factories employing it more or less 

 in their mixtures. 



3. Cost. The estimated first cost of producing cyanamid 

 nitrogen is said to be about 10 cents a pound, but, by the time it 

 reaches the farmer, its cost is probably about the same as that of 

 nitrate and ammonia nitrogen. 



4. Availability. Calcium cyanamid has about the same avail- 

 ability as that of ammonia nitrogen, when compared for the 

 period of a growing season. This would be expected from the 

 fact that when cyanamid is applied to soils, its nitrogen changes 

 into ammonia. Calcium cyanamid itself is not used as food by 

 plants, but first undergoes change into ammonia and then changes 

 more or less to nitrate. 



5. Effects of use of cyanamid. The main product of decompo- 

 sition of calcium cyanamid left in the soil is calcium carbonate. 

 Under some conditions, calcium cyanamid forms in the soil a com- 

 pound called dicyanamid, which has a poisonous effect upon 

 plants. It has been claimed that calcium cyanamid as now put 

 on the market is not liable to undergo this injurious fonn of 

 change. 



6. Advantages. The following claims are made by the manu- 

 facturers for calcium cyanamid : It is quick and progressive in 

 action, has a soil duration of nearly three months, is not washed 

 away by rains, neutralizes free acids, prevents the rotting of 

 bags, is odorless, does not lose nitrogen, can be stored indefinitely 

 without trouble, and is of advantage in damp mixtures. 



CALCIUM NITEATE 



1. Composition. Calcium nitrate, commonly known commer- 

 cially as lime nitrate, is another compound, the nitrogen of which 

 is furnished by means of atmosj^heric nitrogen. This is compara- 

 tively new. Its agricultural use has been largely confined to 

 Europe, only small quantities coming to America before the war, 

 and none since. This material is a mixture of calcium nitrate 

 and other substances, chiefly lime. Pure calcium nitrate con- 

 tains 17 per cent of nitrogen, but the commercial lime nitrate 

 contains only 12 to 14 per cent. 



