Dirt: The Erosion of Civilizations - Kootenay Local Agricultural Society

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mation implied a fundamental change in the landscape. “I infer, from the
rapidity of the denudation caused here by running water after the clearing
or removal of wood, that this country has been always covered with a dense
forest, from the remote time when it first emerged from the sea.” 23 Lyell
saw that clearing the rolling hills for agriculture had altered an age-old balance.
The land was literally falling apart.
One gully in particular attracted Lyell’s attention. Three and a half miles
west of Milledgeville on the road to Macon, it began forming in the 1820s,
when forest clearing exposed the ground to direct assault by the elements.
Monstrous three-foot-deep cracks opened up in the clay-rich soil during
the summer. The cracks gathered rainwater and concentrated erosive
runoff, incising a deep canyon. By Lyell’s visit in 1846, the gully had grown
into a chasm more than fifty feet deep, almost two hundred feet wide, and
three hundred yards long. Similar gullies up to eighty feet deep had consumed
recently cleared fields in Alabama. Lyell considered the rash of gullies
a serious threat to southern agriculture. The soil was washing away
much faster than it could possibly be produced.
Passing through an area of low rolling hills on the road to Montgomery,
Lyell marveled over the stumps of huge fir trees in a recent clearing. Curious
as to how many years it would take to regrow such a forest, he measured
the diameter of stumps and counted their annual growth rings. The
smallest spanned almost two and a half feet in diameter with a hundred
and twenty annual rings; the largest was four feet in diameter and had
three hundred and twenty rings. Lyell was confident that such venerable
trees could never regrow in the altered landscape. “From the time taken to
acquire the above dimensions, we may confidently infer that no such trees
will be seen by posterity, after the clearing of the country, except where
they may happen to be protected for ornamental purposes.” 24 Tobacco,
cotton, and corn were replacing the forest of immense trees that had covered
the landscape for ages. Bare and exposed, the virgin soil bled off the
landscape with every new storm.
In addition to impressive gullies, Lyell ran into families abandoning
their farms and moving to Texas or Arkansas. Passing thousands of people
migrating westward, Lyell reported that those he met kept asking, “Are you
moving?” After showing the eminent geologist some fossils, one elderly
gentleman offered to sell Lyell his entire estate. Lyell pressed him as to why
he was so eager to sell the land he had cleared himself and lived on for
twenty years. The man replied: “I hope to feel more at home in Texas, for
all my old neighbours have gone there.” 25
w estward hoe