INSPECTION OF COMMERCIAL FERTILIZERS 

 (b) Tonnage of Unmixed Fertilizing Materials. 



The method of exjiressing grades in mixed fertilizers adoptetl in 1929 is followed 

 in this publication. It consists in stating the nitrogen guarantee, followed by 

 the ammonia equivalent in parentheses, available phosphoric acid, and potash. 

 The status of the method of expressing fertilizer grade among members of the 

 industry is about the same as last season. The question is still being agitated, 

 and when all members are ready to adopt the system the ammonia statement 

 will be deletetl. 



A study of the tonnage table for mixed fertilizers shows that the three grades 

 having the largest tonnage are 4.11 (5)-8-7, 3.29 (4)-8-4, and 4.11 (5)-3-5. 

 These three grades also had the largest tonnage during 1929. 



In the following table the ten most popular grades are listed in tlie order of 

 the largest tonnage. To effect a comparison and to illustrate how the selection 

 of fertilizer fluctuates from year to year, a similar list is given for 1929. 



The most radical changes noted in the tonnage of these ten grades are the 

 promotion of the 5.76 (7j-3-7 grade from ninth to sixth place, the 4.11 (5)-10-5 

 from twentieth to seventh, and the 4.11 (5)-r2-4 from twenty-third to tenth, 

 and the demotion of the .5.76 (7)-6-5 from seventh to fifteenth. 



Double and multiple strength mixtures totaled 1,667 tons, which is about 

 twice the amount recorded for 1929. 



Of the total tonnage of fertilizer sold, 64.4 per cent was mixetl and 35.6 per 

 cent unmixed materials and pulverized manures. The proportion of unmixed 

 materials was larger by 2 per cent than during 1929. 



