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FEEDS AND FEEDING 



manurial values can be obtained only when the manure is supplemented 

 with a fertilizer supplying phosphoric acid. 



Fertilizing constituents in feeding stuffs and animal products 



The fertility values given in the fourth column mean, for example, 

 that the nitrogen, phosphoric acid, and potash removed from the soil 

 in a ton of oat straw will cost not less than $4.71 if bought in the 

 market in commercial fertilizers. A ton of corn (grain) removes $8.00 

 in fertility, and of wheat, $9.87. Because the legumes usually obtain 

 much of their nitrogen from the air, only a part of the fertility in a 

 ton of clover hay, worth $11.03, may have been taken from the soil. 

 Clover hay is 75 per ct. richer than timothy hay and about 2.3 times as 

 rich as oat straw in fertility. The fertility value of wheat bran is $16.64 

 per ton, while that of the wheat grain is only $9.87. 



Of the feeds listed, tankage has the highest fertility value, $47.22 

 per ton, and cottonseed meal comes next, with a fertility value of $34.51 

 per ton. This explains why these materials, which are such valuable 

 feeds, are often applied directly to the land as fertilizer. Indeed, in 

 1918 about 35 per ct. of the cottonseed meal and 57 per ct. of the high- 

 grade tankage sold in this country was used as fertilizer. Where such 

 protein-rich feeds as cottonseed meal are purchased and fed to live 

 stock on the farm and the manure produced is properly cared for and 

 applied, a double return will be realized a return not only from the 

 feeding value, but also from the manurial value. The manure resulting 

 from each ton of cottonseed meal fed will be worth $23.37, the manurial 



