Dirt: The Erosion of Civilizations - Kootenay Local Agricultural Society

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important was the mix of silt, sand, and clay. Based on bulk chemistry,
Whitney had a point. But Hilgard knew that not everything in a soil was
available to plants.
In 1901 Whitney was appointed chief of the U.S. Department of Agriculture’s
Bureau of Soils. The new bureau launched a massive national soil
and land survey, published detailed soil survey maps for use by farmers,
and exuded confidence in the nation’s dirt, believing that all soils contained
enough inorganic elements to grow any crop. “The soil is the one
indestructible, immutable asset that the Nation possesses. It is the one
resource that cannot be exhausted; that cannot be used up.” 4 Outraged, an
aging Hilgard complained about the lack of geologic and chemical information
in the new bureau’s surveys.
Several years before, in 1903, Whitney had published a USDA bulletin
arguing that all soils contained strikingly similar nutrient solutions saturated
in relatively insoluble minerals. According to Whitney, soil fertility
simply depended on cultural methods used to grow food rather than the
native ability of the soil to support plant growth. Soil fertility was virtually
limitless. An incensed Hilgard devoted his waning years to battling the
politically connected Whitney’s growing influence.
A year before he published the controversial bulletin, Whitney had hired
Franklin King to head a new Division of Soil Management. A graduate of
Cornell University, King had been appointed in 1888 by the University of
Wisconsin to be the country’s first professor of agricultural physics at the
age of forty. Considered the father of soil physics in the United States,
King had also studied soil fertility.
King’s stay in Washington was short. In his new post, King studied relations
between bulk soil composition, the levels of plant nutrients in soil
solutions, and crop yields. He found that the amount of nutrients in soil
solutions differed from amounts suggested by total chemical analysis of
soil samples but correlated with crop yields—conclusions at odds with
those published by his new boss. Refusing to endorse King’s results, Whitney
forced him to resign from the bureau and return to academia where he
would be less of a nuisance.
While Hilgard and Whitney feuded in academic journals, a new concept
evolved of soils as ecological systems influenced by geology, chemistry,
meteorology, and biology. In particular, recognition of the biological basis
for nitrogen fixation helped lay the foundation for the modern concept of
the soil as the frontier between geology and biology. Within a century of
their discovery, nitrogen, phosphorus, and potassium were recognized to
dirty business