HOW MONEY CROPS FEED. 



The substance o£ plants is largely water and varia- 

 tions of woody fiber, yet these comprise no part of 

 what is commonly understood as plant food. More 

 or less by accident was discovered the value of farm- 

 yard manures and general farm refuse and roughage 

 as a means of increasing the growth of plants. In 

 the course of time, the supply of these manures failed 

 to equal the need, and it became necessary to search 

 for other means of feeding plants. The steps in the 

 search were many, covering years of careful investi- 

 gation, and as a result, we have the established fact 

 that the food of plants consists of three different sub- 

 stances, Nitrogen, potash, and phosphates. 



These words are now popular names, and are used 

 for the convenience of the general public. Nitrate of 

 Soda contains an amount equivalent to about 15 per 

 cent, of Nitrogen, 300 pounds to the ton, and cotton- 

 seed meal, for example, about 6 per cent. More 

 than three pounds of cotton-seed meal are necessary 

 to furnish as much available Nitrogen as one pound 

 of Nitrate of Soda. We value the plant food on the 

 amount of Nitrate Nitrogen it contains, and on this 

 account Nitrate has become a standard name for this 

 element of plant food. In like manner, phosphoric 

 acid and potash are standards, hence the importance 

 of farmers and planters familiarizing themselves with 

 these expressions. We always should think of fer- 



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