EXPERIMENT STATION BULLETINS. 

 FERTILIZER ANALYSES. 



BY ANDREW J. PATTEN AND DOROTHEA MOXNESS. 



Bulletin No. 2.39. 



The inspection and analyses of the commercial fertilizers offered for 

 sale in Michigan are made under authority of an act of the Legislature, 

 approved March 10, 1885. The full text of the law has been printed 

 in former bulletins, and its salient points alone will be referred to here. 

 It provides that all commercial fertilizers, retailing for more than ten 

 dollars per ton, shall be accompanied by a statement certifying the 

 number of net pounds in the given sack, the brand, name and address 

 of the manufacturer, and a chemical analysis stating the percentages 

 of nitrogen, of potash, soluble in water, of available (soluble or re- 

 verted) phosphoric acid, and the insoluble phosphoric acid. (Sec. 1.) 

 It provides that the manufacturer, importer or agent (the latter only 

 in case the manufacturer fails to comply with the law), shall pay an- 

 nually a license fee of twenty dollars for each brand offered for sale. (Sec. 

 3.) It provides that any person offering unguaranteed or over-guaran- 

 teed goods, shall be subject to a fine. (Sec. 6.) The full text will be 

 furnished on application. 



RESULTS OF INSPECTION. 



A study of the tables of analyses following shows that 58 of the 

 brands are two-tenths of one per cent, or more below their legal guar- 

 antees in one or more constituents. Sixteen are below their legal 

 guarantees in more than one constituent, and 34 fail to furnish a com- 

 mercial equivalent in promised plant food. 



This is a condition of affairs that should not exist. While it is 

 acknowledged that the nature of the materials used in the manufacture 

 of commercial fertilizers is such as to render perfect mixing almost 

 impossible and that consequently some variation from the guarantees 

 should be expected, still it is certainly true that more than 75 per cent 

 should equal in value the amount of plant food promised. 



The larger number of firms selling fertilizers in the State are un- 

 questionably attemptiiig to comply with the requirements of the law in 

 regard to the composition of their fertilizers and are doing so as nearly 

 as can be expected. The analyses show, however, that there are a few 

 firms whose goods are so far jjelow the legal guarantees as to indicate 

 gross carelessness in mixing, or a deliberate attempt to defraud. Many 

 of the brands below their guarantees this year were the offenders last 

 year. The facts are given in the bulletin, and it is for the farmers to 

 decide whether they will any longer buy from firms whose goods habitu- 

 ally fail to furnish an equivalent in value of plant food guaranteed. 



Manufacturers are supposed to know the composition of the materials 

 used in the mixing of their brands and also of the separate brands when 

 offered for sale, and they are at liberty to make any guarantee they 

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