24 



Average plant food: — 



Mineral nitrogen (per cent), 

 Organic nitrogen (per cent), 



Total nitrogen (per cent), 



Available phosphoric acid (per cent). 

 Potash (per cent), 



Average selling price per ton. 

 Average commercial valuation per ton, 

 Percentage difference. 



Average pound cost of — 

 Mineral nitrogen (cents). 

 Organic nitrogen (cents), 

 Available phosphoric acid (cents). 

 Potash (cents), .... 



Complete Ferti- 

 lize r,s. 



High 

 Analysis. 



1.79 

 1.74 



3.53 



7.80 

 4.12 



Low 



Analysis. 



.94 

 1.26 



7.68 

 2.43 



Ammonl-vted Super- 

 phosphates. 



High 



Analysis. 



2 99 

 1.57 



4.56 

 12 96 



Low 

 Analysis. 



1.22 

 1.84 



3.06 

 8.26 



$68 03 



$53 60 



21 2 



$54 70 



$38 06 



30 4 



$71 73 



$56 26 



21 6 



$57 54 



$39 68 



31 



35.5 

 58.4 

 10 8 

 19 



40 2 

 66 1 

 12 2 

 21.6 



35.7 

 58 6 

 10 8 



40 6 



66.7 

 12 3 



The above table shows that the increase in cost of a pound of mineral nitro- 

 gen has been about 5 cents, of organic nitrogen about 8 cents, of available phos- 

 phoric acid 1.5 cents, and of potash 2.6 cents, when derived from brands which 

 furnished less than 14 per cent of available plant food. If low-analysis mix- 

 tures were used on onions, tobacco and market garden crops, the increase in the 

 cost of the plant food would amount to $15 or SIG per acre. The application of 

 these increased cost figures to the tonnage and average composition of low- 

 analysis complete fertilizers and low-analysis ammoniated superphosphates 

 which were sold in jMassachusetts for the season of 1920 shows that had the 

 Massachusetts farmer bought nothing but high-analysis fertilizers he would 

 have saved over $132,000. 



Following is a statement of the brands of high-analysis and low-analysis 

 fertilizers registered by each company in Massachusetts for the season of 

 1920: — 



W. H. Abbott. 



1 Ammoniated superphosphate. 



