22 



N'o. 1 is satisfactory value at $32.00 per ton, while No. 2, although ofEered at 

 a lower price, is still $6.24 above the actual value. 



Many farmers make the mistake of assuming that a manure of a low price 

 is economical. This, however, is not necessarily the case; indeed, it is usually 

 found that the high-grade manures are in reality the cheaper when valued accord- 

 ing to their composition. 



Unit Values. 



In making a valuation of any fertilizer it should be thoroughly understood 

 that the unit prices for Nitrogen, Phosphoric acid and Potash are based entirely 

 on the market values of the raw fertilizers supplying but one of these plant food 

 elements. These unit values may vary in the different raw fertilizers according 

 to their percentage, composition and price, as follows: — 



Unit Values of Nitbogen. 



% iNitrogen Price Condition 



tPrice or Units of per Unit of or liind of 



Fertilizer per ton. Nitrogen in one ton. Nitrogen. Nitrogen. 



Nitrate of Soda $55 00 15 $3 66 Nitrate 



Sulphate of Ammonia 70 00 19 3 68 Ammonia 



Calcium Cyanamid 48 00 15 3 20 Organic 



Dried Blood Meal 55 00 11 5 00 Organic 



The unit value of organic nitrogen may be obtained from other manures 

 such as Meat Meal and Tankage, which are sold chiefly for their nitrogen content. 

 One per cent, ammonia is equivalent to four-fifths of one per cent, of nitrogen. 

 Thus, if the nitrogen is stated as per cent, of ammonia, to convert to per cent, 

 nitrogen multiply by 4-5, or more accurately .823. 



Unit Values of Soluble oe Available* Phosphoric Acid. 



Price per unit of Conditions 

 tPrice % Phosphoric acid, phosphoric or kind of 



Fertilizer. per ton or units, in one ton. acid. phosphoric acid. 



Superphosphate $16 00 16 $1 00 Acid 



Basic Slag 18 00 12 1 50 Basic or 



Alkali 



Unit Value of Insoluble or Slowly Available Phosphoric Acid. 



A unit value for insoluble phosphate in the organic form can be obtained 

 from the price of bone meal containing 2.5 per cent., or units of nitrogen, and 

 23 per cent, or units of insoluble phosphoric acid, at $30.00 per ton. 2.5 units 

 of nitrogen at the highest unit value (in the organic form) would be $3.68 per 

 unit = $9.20. Subtracting this from $30.00 ($30.00— $9.20) = $20.80 for 23 

 units of Phosphoric acid; = 90 cents per unit of insoluble organic phosphoric acid. 



The market price of Ground Eock Phosphate would establish a unit value 

 for insoluble mineral phosphate which has not been treated with strong acid. 

 Though this kind of phosphate is a popular fertilizer in some places, as yet 

 it is rarely used in Ontario and the price is seldom quoted at present. 



* By available phosphoric acid is meant that which is soluble in water or very weak 

 acid. In the case of a phosphate fertilizer which has been treated with very strong 

 acid the phosphate which remains insoluble is considered of little or no value. 



