Opinion: Measuring the Sycamore

PERHAPS it is a search for order, for scale, for the rules of proportion, some impulse to keep track, but human beings seem hard-wired to take measure of the world around them. It’s why we record everything from rainfall and ice melt to temperature and bird arrival dates. It’s also why I found myself one morning, not long ago, in the meadow of my friends Alex and Blair, in Wallkill, N.Y., along with George Profous, a senior forester with the New York State Department of Environmental Conservation. He was there to measure the old sycamore tree.

The landmark tree on this Hudson Valley property had been nominated by a neighbor as a candidate for the Big Tree Register, maintained by the department to “recognize trees of record size and promote an interest in the trees we come in contact with every day.” Possibly, this tree, with its stippled bark of silver, white and cream camouflage, might even be designated a champion, that is, the largest tree of its species in the state.

The New York State Big Tree nomination form requires a series of calculations. Its formula is a point system that computes the sum of the tree’s height in feet, the circumference of its trunk in inches, and one quarter of its average crown spread in feet.

Mr. Profous took from his bag a 50-foot-long logger’s tape measure and wrapped it around the trunk. The tree’s circumference was 21 feet, 8 inches. “How old does that make it?” I wondered aloud, assuming the size of a tree speaks to its age. Turns out it doesn’t; there is little direct corollary between the years a tree has lived and its measurements. Trees grow faster when they are young, and even taking a core sample tells you only the age of the sample. Mr. Profous guessed that it could be 225 years old now, possibly even dating from the 1780s. But the only way to really determine the age of a tree is to cut it down and count the rings.

Next, Mr. Profous hiked through the thicket of barberry up the hill to measure the height of the tree. He used a clinometer, a device that allowed him to determine the height by triangulating, using the tree, his own position and the angle of the distance between them. It was about 67 feet high.

Finally, he measured the width of the crown, a matter of gauging both its widest and narrowest sections, dividing that by two, then multiplying by .25. But the tree was surrounded by a thicket of multiflora rose brambles, so he pretty much eyeballed it, admitting to “giving it the benefit of doubt.” Which is to say, he added the measure of its widest section — 133 feet — to a generous estimate of its narrowest section — another 133 feet. He did the calculation and reached the figure 33.25.

The sum of the tree’s measurements came to 360.25, a respectable result — but insufficient for championship designation. Just across the Hudson River and to the north, another sycamore on the registry, at 117 feet tall and 27 feet in girth, has a total point count of 475.

His willingness to estimate made sense to me; after all, how can we really compute the stature of such trees? Surely our equations are bound to fall short. We may as well try to put a number to their leaves, assess the weight of their blue shadows on a summer afternoon, or determine any of the other elusive measurements that give the American sycamore its eminence.

In his eloquent meditation on nature, “The Tree,” the writer John Fowles confessed, “I like a kind of wandering wood acquaintance, and no more; a dilettante’s, not a virtuoso’s; always the green chaos rather than the printed map.” Such chaos is rarely accommodated by a point system. There is something in the shade the sycamore casts across the long grass that speaks to the indecipherable.

In an era of climate change and species extinction, it only makes sense that we try to document the minutiae of what remains. But it is just as logical to pause from time to time to consider what cannot be calculated. At a time when we so rely on numbers, big data and statistical analyses, when information systems seem to offer us infinite ways to quantify the world around us, it may be worth remembering that measuring a tree — or a shoreline or coral reef or blooms of native flora — is more than a matter of collecting a few additional bytes of data.

Perhaps we record these natural phenomena, above all, because we fear their impending absence; implicit in nearly any act of measurement is the anticipation of losing the item measured. And when it comes to things like the sycamore tree, we know in our hearts that when they are gone, their loss will be immeasurable.

The author of “The Incidental Steward: Reflections on Citizen Science.”

View the original article here