Throughout seventy or more centuries civilizations were growing across the world, more people, bigger cities, more metal, bigger ships and wars. This created an always-growing need for more wood, food and fiber. Wood is so important to growing civilizations that it was a war strategy to burn an enemy’s forests — that went on right down to World War II, the Japanese floated big air balloons across the Pacific with incendiary devices to land in the Pacific Northwest forests and start fires. But I digress, back to early civilization.
Large areas of forest are cut as every civilization in history has grown and expanded, people needed wood. This could have been ok, kind of, if that was all that happened. Generally speaking, trees want to grow back where they were. But, after the forests were cut, people brought in sheep, goats and cattle to browse and graze the on the land that had been forested and was too steep for crops. People needed the meat and fiber, they thought it made sense. Big mistake! Sheep, goats and cows eat small trees as well as brush, forbs and grass - the trees never had a chance to grow back. The forests that held the sparse moisture that fell and slowly released it so the streams could feed irrigation systems were gone. Overgrazing destroyed the possibility of trees growing back as well as other plants that protected the soil from erosion. Rains eroded the steep soils into streams, the dirty streams fed into the irrigation systems that watered wheat fields, cotton fields and cities. The irrigation systems filled with silt to the point they could not carry water. Agricultural soils became salty because of the erosion from where forests had been. Crops failed, cities failed.
It took several hundred years, but the empire that produced the agriculture to support the great cities and The Hanging Gardens of Babylon became a desert. A few thousand years later the Romans did the same thing to the land they fought over and controlled.
*NOTICE* Our climate in the American West is dry like the Middle East, eastern Europe and north Africa.
How did all this destruction happen? Basically it happened because the people removed the forests, and they didn’t limit the method or number of domestic animals grazing - a bad combination. Where there is grazing land and no one is responsible for it so anyone and everyone can graze it without restrictions, it makes sense for each livestock owner to own and graze as many animals as possible, and that has happened thousands upon thousands of times throughout the world over the past 7000 years. When all livestock owners do that, eventually, every clump of grass, shrub and tree is grazed and re-grazed until the land is barren of plants. Erosion washes away the fine particles of soil - the ones that hold moisture - what is left is a coarse, gravely soil. Grasses, forbs and trees can’t reestablish themselves, the soil has lost its moisture holding capacity, the result is desertification. That series of events played out time and again through history in the Middle-East, North Africa, and a big chunk of Europe and Asia.
These days there is a name for this scenario, it is called “The Tragedy of the Commons.” This social, economic, political, environmental phenomenon was first described and named by the scientist Garrett Hardin and was published in “Science “ magazine in 1968. In a nut shell, it describes a situation where many livestock owners are grazing some land held in common. The result is, it is to each livestock owner advantage to maximize his heard when the grazing land is owned by everyone - or no one - until every blade of grass is grazed to the point that the resource is dead-and-gone. Everyone’s cattle then die and what do you suppose happens to the livestock owners? The overgrazing caused depletion of land productivity, famine, wars for resources and eventually the fall of the civilization.
Of course “The Tragedy of the Commons” does not mean that grazing domesticated livestock, horses, cows, sheep, goats and hogs is the problem. On well managed land, the prudent livestock owner will graze only the number of animals that the land will support year-after-year and that’s good. The problem comes when nobody owns the land and grass, or it is managed only for short term profits, in those situations the livestock owner will REQUIRE the animals to overgraze the land for their own survival, which, in the end, fails. Given a choice, the animals wouldn’t overgraze their survival grass, sixty million bison used America’s Great Plains for millennia and did just fine, they had choices, they grazed and moved, constantly. Domesticated livestock aren’t given choices about moving.
America, in the 19th and 20th centuries, began recognizing this chain of events and interrupted The Tragedy of the Commons. The “commons” were there, in the form of unregulated, uncontrolled public domain lands, the cows and sheep were certainly there and starting to use the public domain as “commons.” Then we Americans did something very smart, or just fortuitous, in the late 1800’s and early 1900’s our government began setting aside unregulated public domain as National Forests and Natural Resource Lands and said, “Forest Service and Bureau of Land Management, manage these lands so the watersheds are protected and the soils are not destroyed by overgrazing and the erosion that follows”. Smart or lucky, that saved the American West. And it is still working, to do otherwise with these now regulated public lands would begin the process of desertification of the American West.
The grazing resource example Garrett Hardin used in his “The Tragedy of Commons” can be thought of as a metaphor for any-and-all natural resources (like our air that we all pump waste into and our aquifers we all drill wells into) that sustain human civilization. That’s a scary and serious thing to think about. We need to do just that (think about it) because this chain of events has played out in civilizations throughout world history, including North America. The ancient Pueblo People in the American Southwest built communities of sophisticated houses and granaries long before European settlement. Their civilization worked for centuries, then the people apparently abandon many of their cities. One explanation, some Archeologists speculate, is that the people cut the near forests and, even though they didn’t have grazing animals, the forests were not reestablished. Their wood source for cooking, tools and structures became too far for them to transport, their communities died.
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