98 



THE PURCHASE OF FERTILIZERS. 



Asa rule, farmers are inclined to purchase fertilizers on the ton ba- 

 sis, without sufficient regard to the content or form of the constituents 

 contained in them. The direct value of a fertilizer is determined by 

 the percentage of nitrogen, phosphoric acid, or potash which it con- 

 tains. Hence, i he buying of a fertilizer is virtually the buying of one 

 or more of these constituents. The more concen rated the material or 

 the richer it is in plant food the less will be the expense of handling 

 the constituent desired. 



The following are illustrations of the methods by which brands may 

 be made up, the differences that may exist in the content of actual fer- 

 tilizing constituents, and the causes of variation in ton prices : 



Formula No. 1. 



Nitrate of soda 5001bs., furnishing nitrogen 801bs., or 4 p. ct. 



Boneblack superphosphate l,1001bs., furnishing phosphoric acid 180ibs , or 9 p. ct. 

 Muriate of potash 4001bs., furnishing potash 2001bs.,or 10 p. ct. 



Total 2,0001bs., furnishing total plant food 4601bs. 



Formula No. 2. 



Nitrate of soda 2501bs., furnishing nitrogen......... 401bs., or 2 p. ct. 



Boneblack superphosphate 1,000 lbs., furnishing phosphoric acid 160lbs., or 8 p. cti 



Muriate of potash 801bs., furnishing potash 401bs., or 2 p. ct. 



Makeweight 6701bs. 



Total 2,0001bs., furnishing total plant food 240 lbs. 



Formula No. 1 shows a high-grade product, both in respect to quality 

 of plant food and concentration, while No. 2 is high-grade only in res- 

 pect to quality. In order that the plant food may be contained in 1 

 ton it is necessary to add what is called " make-weight," or a diluent, 

 usually consisting of substances that contain no direct fertilizing value. 



" High-grade mixtures cannot be made from low-grade materials. 

 Low-grade mixtures cannot be made from high-grade materials with- 

 out adding ' make- weight - ' The advantages of high-grade products are 

 concentration and high quality of plant food." 1 



It will be observed that formula No. 1 contains nearly twice as much 

 plant food as No. 2 ; or, in other words, it will require about 2 tons of 

 a fertilizer made according to formula No. 2 to secure the same total 

 amount of plant food as is contained in 1 ton of No. 1. Now, the ma- 

 terial in No. 2 other than the actual plant food is of no direct ferti- 

 lizing value, but the actual cost of the constituents is considerably in- 

 creased, because the expenses of handling, bagging, shipping, and sel- 

 ling are just double what they would be for No. 1. 



It has been shown by continued studies at the New Jersey Experi- 

 ment Station that the charges of the manufacturers and dealers for 

 mixing, bagging, shipping, and other expenses are, on the average, 

 $8.50 per ton ; and also that the average manufactured fertilizer con- 

 tains about 300 pounds of actual fertilizing constituents per ton. A 

 careful study of the fertilizer trade indicates that these conditions are 

 also practically true for other States in which large quantities of com- 

 mercial fertilizers are used. 



Formula No. 1 would contain 460 pounds of actual available fertiliz- 

 (1) First Principles of Agriculture, E. B. Voorhees, p. 109. 



