14 CONTROL SERIES No. 60 



Of the twenty manufacturers listed above, all but five had an overrun in all 

 three elements of plant food. One manufacturer failed to show an average 

 sufficient to meet the guarantees in either nitrogen or potash. Only one manu- 

 facturer failed to supply enough nitrogen to meet the guarantee, although two 

 others showed average overruns in this element of less than one-tenth of one 

 per cent. In available phosphoric acid satisfactory overruns were noted in all 

 but two instances. Three manufacturers failed to supply a sufficient amount 

 of potash to meet the average guarantee and one showed an average overrun 

 of less than one-tenth of one per cent. All of the other manufacturers showed 

 overruns in excess of one-tenth of one per cent. 

 Explanation of Tables of Analyses. 



Guarantee. This column gives the manufacturer's claim or guarantee for 

 the three elements of plant food, nitrogen, available phosphoric acid and potash, 

 in the order stated. When the nitrogen system is finally adopted by all of the 

 manufacturers, the guarantee of a fertilizer will be the same as the grade. 



With few exceptions, wherever the grade of a fertilizer is used as a part of the 

 trade name the order and form express ammonia, available phosphoric acid and 

 potash. One of the exceptions noted is the Eastern States Farmers' Exchange. 

 Their grade expression refers to nitrogen, available phosphoric acid and potash, 

 conforming to the recommendations of both the National Fertilizer Association 

 and the Committee on Definition of Terms and Interpretation of Results on 

 Fertilizers. 



Commercial Shortages. In the table designated "Mixtures showing a com- 

 mercial shortage of $1 or more per ton," the column headed "Approximate 

 commercial valuation per ton " gives the sum of the valuation of each plant food 

 element computed from the analysis by use of the trade values adopted by the 

 Massachusetts Fertilizer Control for 1931, which appear on a preceding page of 

 the bulletin. 



Under the heading "Approximate commercial shortage per ton" is shown the 

 commercial valuation of the deficiencies or tests found below the guarantee after 

 allowance is made for the value of overruns or tests above the guarantee. 



Deficiencies are emphasized by boldface type. 



Mixtures Substantially Complying with the Guarantee. In addition 

 to the analysis of those fertilizers substantially complying with the guarantee, 

 this table includes also those mixtures that are more or less out of balance; that 

 is, having deficiencies in one or more plant food elements, but having overruns 

 which largely offset the value of the deficiencies. Fortunately, only a very few 

 of these were found, and as the analyses are given in sufficient detail so that they 

 may be readily discovered, thay are not placed in a group by themselves as for- 

 merly, when the more abbreviated tables were used. 



"Number of samples" indicates the number of samples included in the com- 

 posite which was analyzed. 



Inferior Nitrogen. The presence of inferior forms of organic nitrogen is indi- 

 cated by footnotes. 



Potash Forms. Wherever tests for chlorine showed a sufficient amount present 

 to unite with all of the potash found, the source of the potash is designated as 

 muriate. Wherever insufficient chlorine was found to account for all of the po- 

 tash it is evident that forms of potash other than muriate were used. In such 

 cases, the figures under the sub-heading "As muriate" do not imply necessarily 

 that muriate of potash was actually added to the mixture, but that chlorine was 

 present, probably from impurities in the fertilizer chemicals, in amounts to ac- 

 count for the percentage of potash indicated. The balance of the potash found 

 is listed under the sub-heading "In forms other than muriate" and may be de- 

 rived from sulfate, nitrate, or carbonate, as the case may be. 



