6 The Bulletin. 



They are, especially the nitrate of soda, ready to be taken up by plants, 

 and are therefore quick-acting forms of ammonia. It is mainly the 

 ammonia from nitrate of soda and sulphate of ammonia that will be 

 designated under the heading of water-soluble ammonia. 



Organic Ammonia. — The ammonia in cotton-seed meal, dried blood, 

 tankage, fish scrap, and so on, is included under this heading. These 

 materials are insoluble in water, and before they can feed plants they 

 must decay and have their ammonia changed, by the aid of the bacteria 

 of the soil, to nitrates, similar to nitrate of soda. 



They are valuable then as plant food in proportion to their content 

 of ammonia, and the rapidity with which they decay in the soil, or 

 rather the rate of decay, will determine the quickness of their action as 

 fertilizers. With short season, quick-growing crops, quickness of action 

 is an important consideration, but with crops occupying the land during 

 the greater portion or all of the growing season, it is better to have 

 a fertilizer that will become available more slowly, so as to feed the 

 plant till maturity. Cotton-seed meal and dried blood decompose fairly 

 rapidly, but will last the greater portion, if not all, of the growing 

 season in this State. While cotton seed and tankage will last longer 

 than meal and blood, none of these act so quickly, or give out so soon, 

 as nitrate of soda and sulphate of ammonia. 



Total Ammonia is made up of the water-soluble and organic; it is 

 the sum of these two. 



The farmer should suit, as far as possible, the kind of ammonia to 

 his different crops, and a study of the forms of ammonia as given in 

 the tables of analyses will help him to do this. 



VALUATIONS. 



To have a basis for comparing the values of different fertilizer mate- 

 rials and fertilizers, it is necessary to assign prices to the three valuable 

 constituents of fertilizers — ammonia, phosphoric acid, and potash. 

 These figures, expressing relative value per ton, are not intended to rep- 

 resent crop-producing power, or agricultural value, but are estimates 

 of the commercial value of ammonia, phosphoric acid, and potash in the 

 materials supplying them. These values are only approximate (as the 

 costs of fertilizing materials are liable to change, as other commercial 

 products are), but they are believed to fairly represent the cost of mak- 

 ing and putting fertilizers on the market. They are based on a careful 

 examination of trade conditions, wholesale and retail, and upon quota- 

 tions of manufacturers. 



Relative value per ton, or the figures showing this, represents the 

 prices on board the cars at the factory, in retail lots of five tons or less, 

 for cash. 



To make a complete fertilizer the factories have to mix together in 

 proper proportions materials containing ammonia, phosphoric acid, and 

 potash. This costs something. For this reason it is thought well to 



