Cyril G. Hopkins, The Farm That Won't Wear Out
“ More thorough tillage with our improved implements of cultivation is merely "working the land for all that's in it." The use of better seed produces larger crops, but only at the expense of the soil. Even the farm manure is so limited and is spread so thinly with manure-spreaders made for the purpose that it adds but little to the soil in comparison with the crops removed and sold in grain and hay as well as in meat and milk. Clover, as commonly produced and harvested, adds little or no nitrogen to the soil. ”
