SOURCES OF FERTILIZING MATERIALS 53 



Vegetation tests'; that is, tests which show the actual amounts of nitrogen 

 that plants can obtain from nitrogenous products of different kinds, when 

 grown under known and controlled conditions. The results so far obtained, 

 while only serving as a guide, indicate that when nitrate is rated at 100 per 

 cent, blood and cotton seed meal are about 70 per cent., dried and ground 

 fish and hoof meal 65 per cent., bone and tankage 60 per cent., and leather, 

 ground horn and wool waste as low as 2 per cent, to as high as 30 per cent. 

 These figures furnish a fair basis for comparing the different materials, when 

 used for the same purpose. If, for example, the increased yield of oats due 

 to the application of nitrate of soda is 1,000 pounds, the yield from blood 

 and cotton seed meal would be 700 pounds, the yield from dried ground fish 

 and hoof meal would be 650 pounds, from bone and tankage 600 pounds, and 

 from leather, ground horn and wool waste from 20 to 300 pounds." As re- 

 gards the last we are of the opinion that the increase would be nearer nothing 

 at all. 



While these figures may be useful, we would suggest that the cultivator 

 cannot depend upon the same results in practice for the varying conditions 

 under which the plant food is applied, and the atmospheric condition -after 

 the application, might easily make the soluble nitrate the least productive. 

 The practice of all good cultivators is to use the nitrate to some extent in a 

 complete fertilizer mixture, but to place the main reliance for nitrogen for 

 the crop upon the organic forms, since all of the nitrate of soda that is not 

 used at once is rapidly lost to the soil and plants, and the cultivator who de- 

 pends for nitrogen on the nitrate alone will often be disappointed in the 

 result. 



In a number of experiments made at different Stations it has been shown 

 that sulphate of ammonia, in a mixed fertilizer with the muriate of potash, 

 acts as a plant poison. In fact, in certain conditions of the soil, it seems that 

 sulphate of ammonia is about as likely to do harm to the crop as to benefit it. 

 Even when the sulphate of ammonia is simply mixed with stable manure it 

 has given decidedly injurious effects. When mixed with the muriate of 

 potash there is a combination of the chemicals and the chloride of ammonia 

 is formed, which is injurious to vegetation. Another source of organic nitro- 

 gen which is available to the farmers in some localities, is the sea weed which 

 accumulates on the sea beach after storms, and which is largely used by the 

 farmers near the ocean. The sea weeds decay rapidly and furnish large per- 

 centages of nitrogen and potash, but are lacking in phosphoric acid. They 

 are so rich in potash that some authorities rank them among potassic manures, 

 and when mixed with a due percentage of phosphates they furnish a fairly 

 complete fertilizer. One great advantage in the use of sea weeds is the fact 



