25 



From this summary and from the table of analyses it is shown that out of 

 a total of 159 registered brands of ammoniated superphosphates analyzed, 34 

 (21 per cent of the total number) fell below the minimum guarantee in one 

 element; none of the brands were deficient in both elements. Twenty-one 

 brands were found deficient in nitrogen, and 12 in phosphoric acid. Only 

 3 brands showed a serious commercial shortage. This is a much better show- 

 ing than during the preceding year, when 14 brands showed a shortage between 

 50 cents and $3 per ton. 



The brands of ammoniated superphosphates showing commercial shortages 

 of over $1 per ton during the season are as follows, overruns being used in all 

 cases to offset shortages : — 



Bowker Fertilizer Co. — Bowker's Stockbridge 5-8 General Crop, No. 772 : 

 nitrogen found, 3.50 per cent, guaranteed, 4.11 per cent; available phosphoric 

 acid found, 9.50 per cent, guaranteed, 8 per cent. It appears that this brand 

 was stock carried over from the previous season. The inspector, however, 

 reported that the storage conditions were satisfactory, and apparently the 

 material had not suffered by being unduly exposed to weather conditions. 



International Agricultural Corporation, Buffalo Fertilizer Works Branch. — 

 Buffalo Top Dresser, Nos. 90, 104, HI, 116, 594: nitrogen found, 5.50 per 

 cent, guaranteed, 5.80 per cent; available phosphoric acid found, 5.71 per 

 cent, guaranteed, 6 per cent. Another sample of this brand also showed a 

 commercial shortage, as will be seen by the following results: sample No. 

 867: nitrogen found, 4.90 per cent, guaranteed, 5.80 per cent; available 

 phosphoric acid found, 6.94 per cent, guaranteed, 6 per cent. 



New England Fertilizer Co. — New England Potato, Corn and Vegetable 

 Fertilizer, No. 930: nitrogen found, 3.82 per cent, guaranteed, 4.11 per cent; 

 available phosphoric acid found, 8.08 per cent, guaranteed, 8 per cent. 



QUALITY OF PLANT FOOD IN MIXED FERTILIZERS. 



Nitrogen in Complete Fertilizers. — A study of the nitrogen used in 

 the mixed complete fertilizers for 1919 shows that the average total nitrogen 

 found was 2.65 per cent, made up of nitrates and ammoniates, 1.35 per cent, 

 and organic nitrogen, 1.30 per cent. According to these figures, 50.9 per cent 

 of the total nitrogen was found present in the form of nitrates and ammoni- 

 ates and 49.1 per cent in organic form. The quality of the organic nitrogen 

 used in these mixtures is indicated by the following averages: water soluble 

 organic, .28 per cent; water insoluble organic, 1.02 per cent, of which .58 per 

 cent was found active and .44 per cent inactive by the laboratory methods. 



