Dirt: The Erosion of Civilizations - Kootenay Local Agricultural Society

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less, he experimented with agricultural chemistry while running the farm.
After investigating the influence of manure and plant nutrients on crop
growth, Lawes employed chemist Joseph Henry Gilbert to test whether
Liebig’s mineral nutrients would keep fields fertile longer than untreated
fields. Within a decade it was clear that nitrogen and phosphorus could
boost crop yields to match, or even exceed, those from well-manured
fields.
An enterprising friend aroused Lawes’s curiosity and commercial
instincts by asking whether he knew of any profitable use for industrial
waste consisting of a mix of animal ashes and bone. Turning waste into
gold was the perfect challenge for a frustrated chemist. Natural mineral
phosphates are virtually insoluble, and therefore have little immediate
value as fertilizer—it takes far too long for the phosphorus to weather out
and become usable by plants. But treating rock phosphate with sulfuric
acid produced water-soluble phosphates immediately accessible to plants.
Lawes patented his technique for making superphosphate fertilizer
enriched with nitrogen and potassium and set up a factory on the Thames
River in 1843. The dramatic effect of Lawes’s product on crop yields meant
that by the end of the century Britain was producing a million tons of
superphosphate a year.
Bankrolled by substantial profits, Lawes split his time between London
and Rothamsted, where he used his estate as a grand experiment to investigate
how crops drew nutrition from the air, water, and soil. Lawes oversaw
systematic field experiments on the effects of different fertilizers and
agricultural practices on crop yields. Not only was nitrogen necessary for
plant growth, but liberal additions of inorganic nitrogen-based fertilizer
greatly increased harvests. He saw his work as fundamental to understanding
the basis for scientific agriculture. His peers agreed, electing
Lawes a fellow of the Royal Society in 1854, and awarding him a royal
medal in 1867. By the end of the century, Rothamsted was the model for
government-sponsored research stations spreading a new agrochemical
gospel.
Now a farmer just had to mix the right chemicals into the dirt, add
seeds, and stand back to watch the crops grow. Faith in the power of chemicals
to catalyze plant growth replaced agricultural husbandry and made
both crop rotations and the idea of adapting agricultural methods to the
land seem quaint. As the agrochemical revolution overturned practices and
traditions developed and refined over thousands of years, large-scale agrochemistry
became conventional farming, and traditional practices became
dirty business