316 AGRICULTURE 



leases farmers have robbed the soil of its nitrogen, phos- 

 phorus and potassium. Farms located within a hundred 

 miles of the great eastern and southern markets have re- 

 cently been bought for from ten dollars to twenty dollars 

 an acre, when middle western land is selling for one hun- 

 dred dollars to two hundred seventy-five dollars an acre. 

 Much of this eastern and southern land was originally as 

 good as the western, and would be worth a great deal more 

 per acre if it had been properly farmed to conserve its 

 fertility and serve more fully the farm as factory or busi- 

 ness institution. 



There are three principal methods of maintaining the 

 fertility of the soil or increasing its fertility when it has 

 run down. These are: (1) manuring, either with barn- 

 yard manure or by plowing under such plants as clover, 

 alfalfa, cow-peas, or some other green crop; (2) using 

 commercial fertilisers; (3) rotation of crops and diversi- 

 fication. 



2. Barnyard Manure as a Fertiliser 



One of the best evidences of careful farming and good 

 management is a well kept and well used manure heap. 

 Manure should no more be wasted than any other farm 

 product. The annual waste of manures in the United States 

 is equal to our entire wheat crop. 



The value of barnyard manure. Barnyard manure is 

 rich in all three of the elements in which the soil is likely 

 to run short nitrogen, phosphorus and potassium. It has 

 been estimated by experts that if animals are kept in stalls 

 or pens throughout the year, given a reasonable amount of 

 litter for bedding and all the manure saved, the annual value 

 of the manure from each animal will be: horses or mules, 

 twenty-seven dollars ; cattle, twenty dollars ; hogs, eight 

 dollars ; sheep, two dollars. Differently stated, the value of 



