MAINTAINING FERTILITY BY LIVESTOCK 345 



ever, potassium is deficient, potash fertilizers may be used. More- 

 over, scientific grain farming demands that all stalks and straw 

 be returned to the soil. In this manner the draft on the soil supply 

 of potassium is greatly lessened. 



An Ohio Trial in Grain Farming. At the Ohio Station 

 the following system of grain farming has been under test for 

 eight years : 



Year 1 Corn (400 pounds acid phosphate per acre; stalks left on field). 



Year 2 Soybeans for sale as seed (straw returned to the land). 



Year 3 Wheat (300 pounds acid phosphate per acre; straw returned 

 to land, mostly for corn; wheat seeded to clover). 



Year 4 Clover (plowed under for soil improvement, or first crop cut 

 and left on ground and second crop cut for seed). 



This test is on acid soil limed with pulverized limestone. 



This system thus far has resulted in an increase of corn from 



49.6 bushels as the average for the first two years (1910-1911), 

 to 63.5 bushels as an average yield for the seventh and eighth 

 years. The yield of wheat, likewise, was increased from 29.5 to 



32.7 bushels. 



Stock Farming Popular. Stock raising is commonly regarded 

 as the best system of farming. Grain growers are usually advised 

 to become stockmen. It is certain that all farmers cannot be live- 

 stock farmers in the strict sense, because meat and other animal 

 products can never take the place that grains do in human feeding. 



It is generally believed that stock farming is the solution of 

 the soil fertility problem. This, however, is not an established 

 fact. It is true, nevertheless, that crop yields are usually better 

 on stock farms than on grain farms considering the ways in which 

 these two systems of farming are ordinarily carried on. This is 

 because the production of manure in the care of stock has made it 

 possible for the stock farmer to fertilize his land whether he 

 believed in soil enrichment or not. 



Maintaining Fertility by Live-stock Not Probable. Accord- 

 ing to the thirteenth census there is in the United States the eqiva- 

 lent of one animal of the horse or cattle kind 3 to furnish manure 

 for the maintenance of the fertility of 9.07 acres (farm lands, only, 

 considered). One cow at best can, on an average, take care of 

 about two acres a year considering a three-year rotation 

 of corn, grain and clover. Under these conditions soil fertility in a 

 national sense cannot be maintained without the aid of other fertil- 



3 When ten sheep or ten hogs are regarded equivalent to one horse or one 

 cow for fertility maintenance. Ohio Station Bulletin 328 ; 1918, 



