242 



Feeds and Feeding. 



have in tankage, bone meal, and muriate of potash, all of which 

 are standards in their class among commercial fertilizers. Animal 

 manures not only supply plant food, but also benefit the soil by fur- 

 nishing humus, increasing its moisture-holding power, improving 

 the mechanical condition, and favoring bacterial and chemical 

 action. Such being true, it is usually safe to value animal manures 

 on equal terms with commercial fertilizers, based on the content of 

 nitrogen, phosphoric acid, and potash at the market price of these 

 constituents. 



377. Fertilizing constituents of plant and animal products. Table 

 III of the Appendix shows the amount of nitrogen, phosphoric acid, 

 and potash contained in the various feeding stuffs. From this table 

 and Table V the following examples are taken showing the fertil- 

 izing constituents in various plant and animal products : 



Fertilizing constituents in 1,000 Ibs. of various plant and animal products. 



From the table we learn that 1,000 Ibs. of wheat straw contains 

 5.0 Ibs. of nitrogen, while the same weight of timothy hay carries 

 nearly twice as much, or 9.4 Ibs. Clover hay is much richer than 

 timothy hay in nitrogen and especially in potash, tho poorer in phos- 

 phoric acid. Wheat bran contains much more nitrogen, phosphoric 

 acid, and potash than does the wheat grain. This is because the 

 starchy part of the grain, which constitutes most of the flour, holds 

 but little fertility, while the outside portion of the grain, which goes 

 into the bran, contains much of the nitrogen and ash. 



The value of farm manures depends primarily and principally on 

 the character of the food from which they originate, for the animal 

 merely works over the food given to it, appropriating for the forma- 



