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Agricultural Chemistry. 



ditional feeding stuffs. The amount of wheat bran necessary to 

 offset the losses on a farm from which live stock and milk are 

 sold, is shown in the following table. The calculations are based 

 on what a farm of 160 to 200 acres could do. Only potash ana 

 phosphoric acid are considered, as the supply of nitrogen for 

 plant production can be maintained through the growth of legu- 

 minous crops. 



Compensation of Losses on a Farm by Purchase of Wheat Bran. 



The table brings out the fact that 9 tons of wheat bran would 

 offset the losses sustained by the sale of farm animals and milk. 

 Where cream is sold instead of milk, the amount of wheat bran 

 necessary to supply the loss of potash and phosphoric acid in the 

 stock sold would be about 5 tons. 



It must be clear to the student from what has already been 

 said, that losses in fertility are greater in any system of farming. 

 where the crops are sold from the farm than when some form of 

 animal husbandry is followed, especially if no commercial fer- 

 tilizers are purchased. To illustrate this point more fully, the 

 following table adapted from a Minnesota bulletin is given. Four 

 farms, each containing 160 acres, were assumed. On the first 

 nothing but grain was raised and sold. The second was about 

 ''jually divided between grain and stock farming, and the third 

 and fourth were devoted exclusively to stock raising and dairy- 

 ing, respectively. In the last two cases a small amount of the 

 farm produce was exchanged for mill products, which accounts 



