EXPERIMENT STATTOX TU^TXETINS. 395 



A study of the above table shows, first, tliat the average retail price of 

 tlie higher grade formulas was lower, in every case, than the computed 

 value, and second, the average retail price of the lower grade formulas 

 ( those that contain one per cent or less of ammonia with a corresponding- 

 Iv low percentage of i)otash) is higher than the comjjuted value. The dif- 

 ference varies from 1^1.09 in the 1-12-1 formula to -f 10.20 in the i/o-S-l for- 

 nuila. The average difference is considerable and it is evident that in buy 

 ing these low grade formulas the farmer i)ays the fertilizer comi»anies for 

 a service that is of no value. This sei-vice may be accounted for by the 

 filler that would be required to dilute the higher grades or to the cost of 

 handling a larger amount of low grade ammoniate or potash material. 

 Furthermore in the lower grade fertilizer the overhead expense, or cost 

 of nianufacture exclusive of materials, freight, etc., constitutes a larger 

 ])ercentage of the selling price than in the liigher grade fertilizers, all of 

 which accounts for the higher unit cost of the plant-food. 



Once more we wish to call attention to the fact that the computed values 

 given in this table do not necessarily represent the true market valiu's but 

 in comparison with the retail prices they demonstrate that the low grade 

 fertilizers are the most expensive. Also we make no recommendation as 

 to the type of fertilizer one should use, this depends upon many factors 

 which cannot be discussed here but having determined upon the tyi)e of 

 fertilizer, be it acid phosphate or a complete fertilizer, the foregoing data 

 demonstrate the advisability of buying the higher grade formulas. Fur- 

 thermore the aiialytical results published in the following pages show that 

 the higher grade complete fertilizers, as a general rule, carry a better 

 quality of ammoniate or, in other words, the nitrogen in the higher grade 

 complete fertilizers would, in general, be more readily available than the 

 nitrogen of the low grade fertilizers. 



Tn connection with the foregoing discussion it is interesting to note that 

 a movement is on foot among the manufacturers to reduce the number of 

 fertilizer brands and eliminate all those with less than 14 per cent of 

 available plant-food. 



