122 TOBACCO LEAF. 



all the nitrogen from the soil, even when it is supplied 

 in nitrate of soda, which is the most soluble form, 

 because, for one reason, the plant roots do not reach 

 every particle of the soil. Still less can one crop take 

 all the nitrogen from animal, or vegetable, matters, that 

 decompose but slowly in the soil. In any case, there- 

 fore, more or less of the nitrogen contained in the fer- 

 tilizer fails to enter the crop. The tests were made with 

 oats and corn in 147 pots, and resulted for the two years, 

 as follows (Johnson, Britton and Jenkins) : 



AVAILABILITY OF DIFFERENT NITROGENOUS MANURES. 



Column A shows the per cent of the total nitrogen furnished the 

 crops of '94-5 that was available that is, was actually taken up by 

 these crops, the balance of the nitrogen being left in the soil. In Col- 

 umn B, the amount of available nitrogen in nitrate of soda represents 

 100, and the figures beneath show the proportionate availability of 

 nitrogen from the other fertilizers. A B 



Nitrate of soda, 68 100 



Castor pomace, No. 4545, 53 77 



Av. of castor pomace, Nos. 4545 and 4546, 50.5 74 



Cottonseed meal, 49.5 72 



Castor pomace, No. 4546, 48 70 



Linseed meal, 47 69 



Dried blood, 46.5 68 



Dried fish, 45 66 



Dissolved leather, 44.5 64 



Horn and hoof, 42.5 62 



Tankage, 40.5 59 



Steamed leather, 6.5 9 



Roasted leather, 6.5 9 



Raw leather, 1.5 2 



It will be seen that the nitrogen of castor pomace 

 No. 4545 has shown the highest availability of any form 

 of organic nitrogen. The other sample of pomace con- 

 tained more oil, and its nitrogen was not quite as avail- 

 able. Cottonseed meal, linseed meal and dried blood 

 were about equally available, thus scientifically confirm- 

 ing the experience of some of our most careful tobacco 

 growers, who have found linseed meal fully as quick act- 

 ing and effective as a fertilizer as either cottonseed meal 

 or dried blood. Dried fish comes next in order, but it 



