Whether it will pay to use any one or Tu v . e Food for 



, ... . The Kind of Plants 



more fertilizer constituents is a question ^ , 



, , j ... i . Crop an Impor- 



that cannot be answered positively, except Factor in 



by the person who uses them. The relation ^ ( . . ., 



J f . , . , ... . , r Determining the 



of the cost of the fertilizer to the value of A , 



, . , . i i /- j Agricultural 



the increased crop is a variable factor, and, yalue O f tne 



aside from weather conditions, is influenced M: trOffen 

 by the availability of the constituents that 

 is, the proportion that a crop can obtain of the amount ap- 

 plied, the character and composition of the crop grown, and 

 upon the market value of the crop. Because of the facts 

 already pointed out in reference to the constituent Nitrogen, 

 viz., its cost, its variability in usefulness, and its liability to 

 escape in the drains or air, it is of more importance than either 

 of the other two in its bearing upon this point. 



For example, the liberal application of materials con- 

 taining Nitrogen to crops which possess a low market value 

 may result in a maximum production that is, as large an in- 

 crease in yield as it is possible to obtain yet, because the 

 Nitrogen is so expensive, the value of the increased yield may 

 not be equal to the cost of the Nitrogen applied. On the other 

 hand, its application to crops of a high commercial value, 

 though not so completely used and not causing so large a 

 proportionate gain in crop, may result in a large profit, be- 

 cause the cost of the Nitrogen, though considerable, is rela- 

 tively a small item when compared with the increased value 

 of the crop obtained from its use. 



It is shown in the experiments conducted with Nitrate of 

 Soda, on different crops, that in the case of grain and forage 

 crops, which utilized the Nitrate quite as completely as the 

 market garden crops, the increased value of crop, due to 

 Nitrate, does not in any case exceed $14.00 per acre, or a 

 money return at the rate of $8.50 per 100 pounds of Nitrate 

 used, while in the case of the market garden crops the value 

 of the increased yield reaches, in the case of one crop, the 

 high figure of over $263 per acre, or at the rate of about $66 

 per 100 pounds of Nitrate. The Nitrate applied was not 

 better in the one case than in the other, but in the case of the 

 bulky crops the plant required a larger amount of Nitrogen 

 to make a unit of crop than in the case of the market garden 

 group ; besides, it is a crop of low market value dry hay will 

 bring, say, $12 per ton, and a good yield is two tons per acre; 



