Dried Blood

Categories: COMMERCIAL SOURCES OF PLANT-FOOD

There is no more satisfactory source of organic nitrogen

than dried blood of high grade. The best blood, red in color, contains

nearly as much nitrogen as nitrate of soda, running from 13 to 15 per

cent. The nitrogen is not as quickly available as that in the nitrate,

but is more so than that in any other form of organic nitrogen. One

would rarely go amiss in the purchase of dried blood as a carrier of

nitrogen if the rice were relatively as low as in the case of nitrate

of soda, but he should not let any prejudice in favor of animal origin

of fertilizers lead him to pay an excessive price per pound for the

nitrogen contained in it. Such a prejudice has caused the nitrogen in a

good red blood to sell for one half more per pound than in nitrate of

soda, and it is not a good purchase on that basis.



The lower grades of dried blood on the market contain as low as 6 per

cent of nitrogen, and the animal refuse put into it gives it a content

of a few per cent of phosphoric acid. This black blood is very variable

in composition, and should always be accompanied by a guaranteed

analysis.