27 



about 54.4 per cent, of the total nitrogen was present in mineral forms and 

 45.6 per cent, in organic forms. It was found that .38 per cent, of the organic 

 nitrogen used was water soluble and 1.07 per cent, was water insoluble. Of 

 this latter, .60 per cent, was found active and .47 per cent, inactive by labora- 

 tory methods. The percentage activity of the total nitrogen was about 85 

 per cent,, of the total organic nitrogen 67.6 per cent., and of the water insoluble 

 organic nitrogen 56 per cent. 



Brands of Mixed Fertilizer showing Inferior Forms of Nitrogen. 

 — Ten out of a total of 108 brands of complete fertilizers and 3 out of a total 

 of 151 brands of ammoniated superphosphates, besides 1 brand of partially 

 dried peat or humus and 7 brands of pulverized sheep manure, were found to 

 contain organic nitrogen of questionable quality, and are indicated in the 

 tables of analyses by the word " inferior " in the column headed " Quality of 

 water insoluble organic nitrogen." 



The following table gives a detailed report of the studies on brands of 

 complete fertilizers and ammoniated superphosphates which have shown the 

 presence of inferior forms of organic nitrogen. Although the list is somewhat 

 smaller than last season, it may not indicate a much better showing, for the 

 reason that fewer brands have been offered to the trade. If it were deemed 

 advisable by any manufacturer to use a couple of hundred pounds of peat or 

 other low-grade organic substance in order to insure a proper mechanical con- 

 dition, there would be no objection to such a practice, provided the nitrogen 

 which it carried was not included in the guarantee and a proper notation of 

 its use was included in the printed label on the package. The following brands 

 were reported in 1917 as containing organic nitrogen of inferior quality, in 

 fact some of these brands have for years borne this criticism: Armour's 1-8-2, 

 Carter's Worm Eradicating Fertilizer, Mapes Potato Manure, Mapes Corn 

 Manure, and Essex Grain, Grass and Potato Fertilizer. 



The fact that certain brands of mixed goods appear in the table year after 

 year, showing evidences of the presence of inferior forms of organic nitrogen, 

 would indicate that at least some fertilizer manufacturers were not paying 

 sufficient attention to the manufacture of their base goods mixtures. Most 

 of the fertilizer products containing nitrogen of low availability may be so 

 treated as to make them sufficiently available to pass inspection by the well- 

 known laboratory methods. Many of the largest fertilizer companies oblige 

 their chemists to follow up this nitrogen availability work very closely, and 

 are constantly improving their processes of treatment of the lower grade 

 materials, with the result that a brand is very seldom discovered which shows 

 the presence of a sufficient percentage of inferior organic nitrogen to cause 



