Dirt: The Erosion of Civilizations - Kootenay Local Agricultural Society

the introduction of clover and other nitrogen-fixing plants into crop rotations
in the eighteenth and early nineteenth centuries. Crop yields at the
start of the eighteenth century were not all that much greater than medieval
levels, implying that increased agricultural production came largely from
expanding the area cultivated rather than improved agricultural methods.
Wheat yields had risen by just a bushel and a half over medieval yields of
ten to twelve bushels per acre. Yet by 1810 yields had almost doubled. By
1860 they had reached twenty-five to twenty-eight bushels an acre.
Increasing labor needed to harvest an acre of crops implies that crop
yields rose over time. The number of person days required to harvest an
acre of wheat increased from about two around 1600 to two and a half by
the early 1700s, and then to just over three in 1860. Overall crop yields
increased by two and a half times in the six hundred years from 1200 to
1800. So despite increasing yields, the tenfold population increase primarily
reflected expansion of the area under cultivation.
During the same period about a quarter of England’s cultivated land was
transformed from open, common fields to fenced estates. By the end of the
eighteenth century, common fields had almost disappeared from the English
landscape. Loss of the common lands meant the difference between
independence and destitution for rural households that had always kept a
cow on the commons. Dispossessed, landless peasants with no work depended
on public relief for food. Seeing the economic effects of the transformation
of the English countryside, Board of Agriculture secretary
Arthur Young came to see land enclosure as a dangerous trend destroying
rural self-sufficiency. But enclosing and privatizing the last vestiges of communal
property conveniently pushed a new class of landless peasants to
seek jobs just as laborers were needed in Britain’s industrializing cities.
By the early nineteenth century, British farms had developed into a
mixed system of fields and pastures. A roughly equal emphasis on cultivation
and animal husbandry provided for constant enrichment of the soil
with large quantities of manure, and cover crops of clover and legumes.
English population growth mirrored increases in agricultural production
from after the Black Death to the Industrial Revolution. Between 1750
and 1850, England’s cereal production and population both doubled. Did
a growing human population drive up demand for agricultural products?
Or did increased agricultural production enable faster population growth?
Regardless of how we view the causality, the two rose in tandem.
Nonetheless, as the population grew, the European diet declined. With
almost all of the available land in cultivation, Europeans increasingly sur-
let them eat colonies 99