Custom Search

Monday, July 14, 2008

Trees: When the truth is dug up, theories are sometimes uprooted

In "The Life of Trees: Their "most simple and beautiful oneness" in Books & Culture, Alan Jacobs writes about trees, reminding us of how little we really know about the life forms that surround us:
But perhaps the most interesting fact to be gleaned from these books—and from Richard Preston's The Wild Trees—is this: much of our knowledge about trees is of recent vintage, and there is still a great deal about these creatures that we do not know. Rackham points out that two great storms that swept across Britain in 1987 and 1990 and uprooted thousands of old trees created surprise and consternation in many botanists: all along they had been describing the long taproots that anchored such trees deep in the ground, but the storms revealed that the taproots didn't exist. Even the largest trees can have roots just a couple of feet deep: they extend horizontally vast distances, but the taproots that saplings (especially oaks) send down are soon supplanted. Preston describes the work of Steve Sillett, of Humboldt State University in California, and a small group of other scientists who in the past fifteen years have discovered what really goes on in the canopies of our tallest trees—something which earlier botanists had tried, with limited success, to explore by floating above the forests in balloons. Sillett and company simply climb the trees, risking life and limb every time they do it, and in the process are discovering the phenomenally complex ecosystem flourishing in those heights. Preston, who became a climber himself and joined Sillett on some of his expeditions, found in the crowns of some Eastern trees flying squirrels so unfamiliar with human beings that they allowed him to scratch their heads, and life two hundred feet farther up, in those California redwoods, is even stranger. As one scientist vividly remarked, atop some of the tallest redwoods, with their dense and interlocking multiple crowns, you could put showshoes on and throw a Frisbee around. O brave new world indeed.
And so much of what we know is wrong:

Conservationists," says Rackham, "have a record of trying to play God and rectifying God's mistakes as well as humanity's. Often they make woods fit a predetermined theory (which theory depends on how long ago they were at college) rather than listening to the woods and discovering what each wood has to contribute to conservation as a whole." It's now well-understood that the most catastrophic of these attempt at God-playing was the practice—very common throughout the 20th century, especially in North America and in Brazil, and not yet everywhere rejected—of trying to eradicate forest fires. This overzealousness deprives woodland ecosystems of the vital benefits of occasional burning, and, worse, insures that when fires do start they find so much combustible material that they become superfires, with dire consequences for forests and people alike.
Essentially, if all mature trees are protected from destruction, there will be no habitat for the many life forms that depend on new growth and mid-life forests, to say nothing of clearings. A sound ecology incorporates all stages of life, including rotting logs. Jacobs also notes,

It's interesting to see that people who love trees and know them intimately, as opposed to those who have merely general instincts for conservation, tend not to erect ideological barriers between the human world and "Nature." Rackham's deeply committed but pragmatic and nonideological approach credits woodlands with a remarkable ability to manage themselves, and sees a great deal of wisdom in many of our ancient practices of woodcraft—practices formulated when we couldn't dominate our environment and so had to learn to be stewards of it.
It's a lovely essay; it communicates a love for trees while acknowledging the short-sightedness of the sort of urban environmentalism, where the busybody has, alas, picked "nature" as his target.

I had a run-in with just such folk a decade ago when the maple tree in my front yard was struck by lightning. A huge branch blocked the street for hours. Because it was an old tree, planted too close to the sidewalk and now quite disfigured, the city condemned and removed it. Well! To hear some people, you would think we had murdered the legendary Spirit of the Trees! In fact, a fine young tree now stands in its place, and life goes on, somewhat closer to the ground, -at least for now.

(Note: The image is from Free Fotos.)


Who links to me?