Dirt: The Erosion of Civilizations - Kootenay Local Agricultural Society

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Figure 10. Miniature from an early-sixteenth-century manuscript of the Middle
English poem God Spede ye Plough (original held at the British Museum).
ism. Simkhovitch hypothesized that an individual farmer could not keep
enough cattle to maintain the fertility of his plot, but a village’s livestock
could collectively fertilize the commons enough to slow their degradation.
Simkhovitch believed that the already degraded state of the land made
cooperation the way to survive—a notion contrary to the “tragedy of the
commons” in which collective farming was thought to have caused land
degradation in the first place.
Simkhovitch argued that by failing to maintain their soil, ancient societies
failed themselves. “Go to the ruins of ancient and rich civilizations in
Asia Minor, Northern Africa or elsewhere. Look at the unpeopled valleys,
at the dead and buried cities. ...It is but the story of an abandoned farm
on a gigantic scale. Depleted of humus by constant cropping, land could
no longer reward labor and support life; so the people abandoned it.” 1 The
introduction of alfalfa and clover into European agriculture helped rebuild
soil fertility, Simkhovitch insisted. Noting that there were no hay fields
before the sixteenth and seventeenth centuries, he suggested that enclosure
of common fields allowed converting enough land to pasture to raise the
cattle and sheep needed to manure the land and thereby increase crop
yields.
The conventional explanation for the low crop yields of medieval agriculture
invoked a lack of enough pasture to supply cultivated land with the
manure needed to sustain soil fertility. Until recently, historians generally
considered this to reflect ignorance of the value of manure in maintaining
soil fertility. It now seems as likely that medieval farmers knew that keep-
let them eat colonies