322 



EXPEKIMENT STATION EECOED. 



cent for sodium nitrate to 90 per cent for ammonium sulphate is correct in most 

 cases. However, the ammonium sulphate gave better yields in a few instances 

 than the sodium nitrate. From the results of his own experiment on sugar 

 beets, with superphosphate and sodium nitrate as the basal fertilizer, the au- 

 thor found that a fall application of ammonium sulphate gave better yields than 

 "^-a spring application. 



The sokibility of organic forms of nitrogen in fertilizers, J. P. Street 

 (Connecticut State 8ta. Rpt. 1909-10, pt. 5, pp. Ji30-Jili2). — As preliminary to a 

 study of the availability to crops of water-soluble and permanganate-soluble 

 forms of nitrogen, and to devise if possible a laboratory method for determin- 

 ing the agricultural value of organic forms of nitrogen, the ammonia evolved 

 on distillation with magnesia, the water-soluble, and the permanganate-soluble 

 nitrogen were determined in 117 samples of organic nitrogenous materials used 

 in fertilizer mixtures. These included 35 kinds of materials of all grades of 

 a.gricultural value. The average results obtained with the principal materials 

 are given in the following table : 



SoluhilUy of nitrogen of fertilizinn materials. 



Material. 



Num- 

 ber of 

 sam- 

 ples. 



Nitrogen. 



As am- 

 monia. 



As 

 water- 

 soluble 



As per- 



man- 



ganate- 



soluble 



or- 

 ganic. 



As in- 

 soluble 



or- 

 ganic. 



Solubility of or- 

 ganic nitrogen. 



Total. 



Water- 

 insolu- 

 Tile or- 

 ganic. 



Dried blood 



Hoof meal 



Cotton-seed meal. 



Bone 



Pried fish 



Tankage 



Tankage (alleged) 

 Castor pomace. . . 

 Peruvian guano. . 

 Garbage tankage. 



Sheep manure 



Peat 



Tobacco stems . . . 



Per ct. 



11.67 

 15.00 

 7.03 

 3.84 

 7.94 

 5.80 

 5. .57 

 5.24 

 5.40 

 2.54 

 2.42 

 2.89 

 2. .51 



Per ct. 

 0.11 

 .35 



.08 

 .00 

 .67 

 .27 



2.33 

 .08 



1.77 

 .07 

 .39 

 .09 



Per ct. 

 0..32 

 1.19 



.08 

 1.12 

 1.69 

 1.52 

 .65 

 .68 

 1.11 

 .40 

 .38 

 .08 

 .52 



Per ct. 



10.77 



12.78 



5.85 



2.56 



5.07 



3.61 



1.63 



3.95 



2.02 



1.06 



.79 



1.13 



.44 



Per ct. 



0.47 

 .68 

 .42 

 .16 

 .51 

 .40 

 .96 

 .53 

 .28 



1.01 

 .86 



1.59 

 .08 



Per ct. 

 96 

 95 

 94 

 90 

 93 

 93 

 70 

 90 

 92 

 59 

 58 

 43 

 59 



These results indicate that digestion with a 2 per cent neutral solution of 

 potassium permanganate " may offer a means of determining the approximate 

 relative value of the organic nitrogen found in commercial fertilizers." 



The method was applied to 252 samples of mixed fertilizers with the following 

 results : 



SoIuMlity of nitrogen of mixed fertilizers. 



