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ambience: Non-descript outdoor ambience, birds
There are first place sports teams, why not champion trees? I’m Jim Metzner, and this is the Pulse of the Planet. It turns out there is a National Register of Big Trees. It’s been kept by the American Forests Organization for over 60 years. These are typically the largest living examples known of specific species of trees, determined by a point system based on the trees measurements. Now, there’s a 200 year old white pine tree growing in my backyard, and in order to see how my tree stacked up against the current champion white pine, I contacted Bruce Robinson of the New York State Big Tree Program.
“We need to know it’s size in diameter, we need also to know the height. The third measurement is the crown spread. How wide are those branches?”
Now, Robinson’s first step is to mark the circumference of the tree with a string at a distance of about four feet from the ground. Well next, Robinson is ready to measure the height of the tree, and all that he needs is a stick the length of his arm. Holding the stick upright at arm’s length so that the bottom of the stick appears to be level with the base of the tree, from his point of view, he backs up until the top of the stick appears to be even with the top of the tree.
“And we’re simply making similar triangles. Once we have arrived at that point, we will measure the distance from where we’re standing to the base of the tree, and that will be the height of the tree.”
And then Robinson determines the average crown spread of the tree and adds that number to the height and circumference. My tree’s total comes to two hundred and ninety-two points – not bad, but not even close to the current champion white pine’s total of three hundred sixty-three points. Well, it’s still the tallest tree on the block.
Pulse of the Planet is presented by the National Science Foundation.
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