May 31, 2003

THE PILGRIM'S PROGRESS

The Force That Drives the Flower: What is it about fecundity that so appalls? Is it that with nature's bounty goes a crushing waste that threatens our own cheap lives? (Annie Dillard, November 1973, The Atlantic Monthly)
The growth pressure of plants can do an impressive variety of tricks. Bamboo can grow three feet in twenty-four hours, an accomplishment that is capitalized upon, legendarily, in that exquisite Asian torture in which a victim is strapped to a mesh bunk a mere foot above a bed of healthy bamboo plants whose woodlike tips have been sharpened. For the first eight hours he is fine, if jittery; then he starts turning into a colander, by degrees.

Down at the root end of things, blind growth reaches astonishing proportions. So far as I know, only one real experiment has ever been performed to determine the extent and rate of root growth, and when you read the figures, you see why. I have run into various accounts of this experiment, and the only thing they don't reveal is how many lab assistants were blinded for life.

The experimenters studied a single grass plant, winter rye. They let it grow in a greenhouse for four months; then they gingerly spirited away the soil--under microscopes, I imagine--and counted and measured all the roots and root hairs. In four months the plant had set forth 378 miles of roots--that's about three miles a day--in 14 million distinct roots. This is mighty impressive, but when they get down to the root hairs, I boggle completely. In those same four months the rye plant created 14 billion root hairs, and those little things placed end to end just about wouldn't quit. In a single cubic inch of soil, the length of the root hairs totaled 6000 miles.

Other plants use water power to heave the rock earth around as though they were merely shrugging off a silken cape. Rutherford Platt tells about a larch tree whose root had cleft a one-and-a-half-ton boulder and hoisted it a foot into the air. Everyone knows how a sycamore root will buckle a sidewalk, a mushroom will shatter a cement basement floor. But when the first real measurements of this awesome pressure were taken, nobody could believe the figures.

Rutherford Platt tells the story in The Great American Forest, one of the most interesting books ever written:

In 1875, a Massachusetts farmer, curious about the growing power of expanding apples, melons, and squashes, harnessed a squash to a weight-lifting device which had a dial like a grocer's scale to indicate the pressure exerted by the expanding fruit. As the days passed, he kept piling on counterbalancing weight; he could hardly believe his eyes when he saw his vegetables quietly exerting a lifting force of 5 thousand pounds per square inch. When nobody believed him, he set up exhibits of harnessed squashes and invited the public to come and see. The Annual Report of the Massachusetts Board of Agriculture, 1875, reported: "Many thousands of men, women, and children of all classes of society visited it. Mr. Penlow watched it day and night, making hourly observations; Professor Parker was moved to write a poem about it; Professor Seelye declared that he positively stood in awe of it."

All this is very jolly. Unless perhaps I were strapped down above a stand of growing, sharpened bamboo, I am unlikely to feel the faintest queasiness either about the growth pressure of plants or their fecundity. Even when the plants get in the way of human "culture," I don't mind. When I read how many thousands of dollars a city like New York has to spend to keep underground water pipes free of ailanthus, ginko, and sycamore roots, I cannot help but give a little cheer. After all, water pipes are almost always an excellent source of water. In a town where resourcefulness and beating the system are highly prized, these primitive trees can fight city hall and win.

Magazines like The Atlantic, the New Yorker, The Nation, New Republic, TIME, and others, that have been publishing for decades and longer, have so much great material in their archives, it's too bad they don't post more of it. Posted by Orrin Judd at May 31, 2003 11:41 PM
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