Farmers of Forty Centuries

Farmers of Forty Centuries: Or Permanent Agriculture in China, Korea and Japan, is an invaluable book written in 1911 by soil scientist Franklin Hiram King after he was expelled from the USDA for warning about the impending loss of soil through erosion and loss of soil fertility in American agriculture twenty years before the dust bowl.

Professor King, out of a job, traveled to East Asia to observe how it was that these peoples could farm the same ground for thousands of years without depleting the soils - a key counterpoint to his arguments that soil fertility was finite.

In turn-of-the-century China, Korea and Japan, King found a finely tuned and highly productive system of land-limited and intensive agriculture relying on crop rotation, polyculture, and carefully managed soil fertility including the use of humanure.

He observed that asian agriculture was capable of supporting very high population densities and was correspondingly highly labor intensive.