Monday, February 13, 2006

1491, Post 3 of 4: Primeval Woodland or Managed Garden?

kw: book reviews, nonfiction, history, western hemisphere

When I was twelve or so, I was walking in a forested area in late Summer. I began to notice apples on the ground, then cherries. I looked up, and there was fruit everywhere. Not on every tree, but on many, particularly a number of old, gnarly trees. It didn't take long to figure out that this piece of now-public land was once a farmer's informal orchard: half a dozen apple trees, some cherry trees, and I found a stand of small plums.

Visitors from temperate areas (mainly Europe and North America) who visit the tropics often remark that life must be easy, you can pick fruits and other foods almost anywhere. Contrary to my childhood experience, though, very few consider that they might be in ancient orchards. As it happens, writes Charles C. Mann in 1491, the poster child of tropical forests, the Amazon "jungle," is actually at least one-ninth "'anthropogenic'—directly or indirectly created by humans."

The tropics are rich, no doubt. In "unmanaged" forest, about 20 percent of the plants bear edible fruit. But over large, widespread areas, fully half the plants are sources of food. It is likely that many of the "20-percenter" forests were once managed, but have been fallow since the epidemics of 500 years ago.

And what of the great American grasslands, the Western steppes and Mideastern tall grass prairies? Or the large open areas in the "impenetrable" forests of the East? Early reports tell of the Indians' use of fire, to prepare agricultural land, to create charcoal for enriching fields, for managing the species that would grow, and for keeping the forest open for travel. The open, cathedral-like forests once seen from Pennsylvania (Penn's Woods...except they weren't his) to Minnesota and south to Kentucky were burned yearly by their earlier inhabitants. By the late 1500s, the cathedral-like aspect had pretty much vanished, and white homesteaders cut down and burned off the now-impenetrable forest for farmland.

If a forest burns every year, the grasses, forbs, and shrubs of the understory burn and char, and the trees are little affected. It is only when the understory gets overgrown that fire can endanger trees. If you want to turn a meadow in Pennsylvania into forest, as quickly as possible, first let it burn over in Autumn. In the Spring, scatter acorns and seeds of elm, ash, maple, and other trees. Then wait a few years until you have a few hundred 15- to 25-foot hardwood trees per acre and burn it, again in Autumn. If a lightning strike starts a fire before that, let it burn. Either way, many of the trees will survive. Thereafter, burn the underbrush yearly. You'll have a nice, open forest with dense shade within a decade or so. Thereafter, the "ceiling" will rise by a few feet per decade until it tops out at 50-60 feet.

Further west, the central North American grasslands are a product of fire. The Corn Belt was once covered with "buffalo grass," that fed browsing prey. Prior to 1492, there were comparatively few bison; their population explosion in the 1700s was a symptom of environmental collapse once the "burners" died off and the plants changed. The resulting Sioux and other bison-hunting cultures were no more than a century old when Custer was lured to his death in Montana. Rather, the older culture mixed grain growing with the hunting of pronghorn and deer, and perhaps were taking steps to domesticate the larger Whitetail deer, much as the Lapps domesticated Caribou to create Reindeer. We'll never know.

I live in Delaware. In some of the State parks, there are hardwood trees 18 to 24 inches in diameter and forty feet tall, and in wetter areas, 40-inch sycamores sixty feet tall. A little inquiry determines that none of these trees is a century old. An oak that died in a bit of forest near my home, which was two feet in diameter (at breast height, where trees are properly measured), died of root fungus and was felled. Its stump has sixty growth rings. My house is 62 years old, so that tree was planted or first sprouted two years after my development was built. In my yard I have two oaks and a maple, all about 18 inches in diameter, that are 44 years old, which I know because my neighbor told me the year she saw them planted.

Some of the former farms in northern Delaware were farmed, abandoned, farmed again...four cycles since the 1600s. Today large trees grow on those lands, but you can see old walls running through. The upshot is, not having visited the Pacific northwest, I've never seen "virgin" forest...but what I have seen looks pretty good to me.

The author concludes in one section, "Until Columbus, Indians were a keystone species in most of the hemisphere. Annually burning undergrowth, clearing and replanting forests, building canals and raising fields, hunting bison and netting salmon, growing maize, manioc, and the Eastern Agricultural Complex, Native Americans have been managing their environment for thousands of years."

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