118 



These minerals were also applied to another series of pots receiving 

 no nitrogen. 



Mustard was planted July 5 and harvested August 13. The fol- 

 lowing table gives the yield per pot in green mustard, dry matter, and 

 nitrogen : ♦ 



Yield of mustard in pots fertilized ivith different forms of nitrogen. 





Green 

 Mustard. 



Dry 

 Matter. 



Nitrogen. 





Grams. 



Grams. 



Grams. 



Minerals, no nitrogen 



1,164.0 



124.5 



3 



304 



Green alfalfa 



1,504.0 



147.8 



4 



519 



Stable manure 



1,606.0 



154.9 



5 



277 



Sulphate of ammonia and minerals 



1,627.5 



148.2 



5 



.362 



Comparing the amount of green mustard produced on the nitrogen 

 pots with that on the pots receiving no nitrogen, there is found an in- 

 crease of 463.5 gm., for sulphate of ammonia, 442 gm., for stable 

 manure, and 340 gm., for 'green manure. This is equivalent to saying 

 that the nitrogen of stable manure was 95 per cent, and that of young 

 alfalfa 73 per cent, as effective as that of sulphate of ammonia. 



Comparing the amount of nitrogen in the mustard growing on the 

 nitrogen pots with that on the pots receiving no nitrogen, we find an 

 excess of 2.058 gm for sulphate of ammonia, 1.973 gm. for stable 

 manure, and 1.215 gm. for green manure 



Comparing this excess with the amount of nitrogen applied (4.1168 

 gm. to each pot) it appears that 50 per cent, of the nitrogen in sulphate 

 of ammonia, 48 per cent of that in stable manure, and 30 per cent of 

 that in green alfalfa was utilized by mustard in its six weeks of 

 growth. 



The nitrogen of stable manure was more immediately available in 

 the author's experiments than in those of previous investigators, a fact 

 which he ascribes to his having used the manure with its full compli- 

 ment of urine as soon as it came from the animal. — (J. Kuhn, abstract 

 in Experiment Station Record.) 



