Sunday, March 24, 2013

The Quest for the Oldest, Tallest Trees



Twenty-something years ago, I came to know Bob Leverett. I had been told he was searching for and documenting what remaining old growth forest there was in western Massachusetts. I immediately knew this was a fellow I had to meet and, hopefully, tag along with. Old growth forest in Massachusetts?? This I just had to see.

At that time, Bob and his son Rob spent virtually every weekend (and then some) scouring the Berkshire hill country, and other places up and down the eastern U.S., for signs of remnant old growth forests. What they found that fit that category in Massachusetts was relatively small, scattered patches that, while not necessarily "virgin" forest, had characteristics that distinguished them from the typical second growth forests that are quite extensive in the Bay State, and most of the northeast.

Bob propping up a respectable Black Cherry
One of those characteristics, which I oh-so-quickly came to know, was that the bulk of these aged trees were rooted on land a mountain goat would be almost happy to negotiate regularly. Almost.



I vividly remember Rob, who was an energetic, athletically-built kid of maybe 18 years, scampering up, down, and across the heavily wooded near-vertical slopes like a deer, lacking the patience to slough along the trail at the bottom of the hill with his dad and me. Bob, you see, had a mission and usually a destination in mind, and would point his nose and toes in that direction, anxious to reach the goal. Rob had a mission of his own- to seek out "new"old trees to be measured and admired- but had no particular destination to constrict his trans-elevational travels. If you plotted our typical courses, the track that Bob and I took would be a fairly straight line, doubling back on itself on the return to the car at day's end;  Rob's would be a dizzying zig-zag up and down the mountains on one or both sides of a ravine trail.

I'd pay good money right now to once again hear Rob's barely perceptible shout from way up there on the mountain, "Dad, you gotta come up here .... (muffled words) .... ancient, ancient trees... (muffle muffle muffle)..". And Dad would cast his gaze upsloap, in the hope of being able to actually see Rob somewhere up there; that failing, he'd yell back, "uhh, ok Rob, we'll come up...". Not that Bob lacked the energy or the desire to see what Rob had discovered this time, because Rob had a knack for finding great trees; no, I suspect it was just that the day's mission was being temporarily sidetracked.

And what was the mission? Bet your father's prized cigars on this: it was to measure (or re-measure) that lofty hemlock (or white pine, white ash, sugar maple, etc) up the brook a ways ("you remember- the one at 1109 feet in elevation on the side of the gorge, above the 122-foot tall pine with the witch's broom top..."). "Yes. Yes Bob, I remember the one. That was where we both stepped in that deep hole hidden under the ferns, right"?

 Bob is the number one man of numbers I've ever known. He has a reverence for old growth forest, its timeless solitude, and its lack of human meddling, to put it simply; but I think his self-admitted obsession with discovering, cataloging, and (most of all) measuring the tallest, biggest trees he can locate is at least as strong a motivation for wearing out hiking boots and legs as any. He's been at it for decades now, and I dare say he can quote from memory each and every data point he's authored, and those of many others. Those of you who've had the pleasure of burning every last calorie from a hearty breakfast traipsing over the hills with Bob will back me up on that. We've all listened to him describing the variations in temperature, soil conditions, forest composition, windthrow history, etc, at each topographic contour line up a mountainside. He's a tad slower ascending the slopes now, but no less enthusiastic.
Measuring circumference of White Pine

Bob's toolkit of twenty-odd years ago consisted of a 100-foot tape measure, an inclinometer, calculator, pad and pencil. Determining a tree's height seemed a simple matter of basic trigonometry... measure a baseline along the ground perpendicular to the tree's base, find the angle of elevation to the tree's top, then calculate the height of the tree using trigonometry. Not much has changed, really, except for the addition of a shiny new laser rangefinder or two, which make the results much more accurate. And that's truly what it's all about for Bob. If you tell him you measured a maple's height and found it to be133, he'd likely look at you expectantly for a moment, waiting to hear the decimal positions-- one thirty-three point four seven.
Can you find the very top ?


Actually, arriving at the magic number of a tree's height is seldom as simple a matter as I've described. In theory it is, but in practice, it's more frustrating. The procedure works fine if the tree is standing arrow-straight (ie, perfectly vertical) in an open field, on flat ground, where you can run your tape 100 feet or so from the tree to a point in the field, and from there get an unobstructed view of the very top of the tree.

But since the subjects are in-forest trees growing on mountainous terrain, things get more complicated. Just trying to get a clear baseline to the tree is an effort. Other trees obscure the view of the treetop; even if it's visible, it's not that easy to pick out which leafy twig up there is actually the highest point of the tree from well over a hundred feet away. Then, if the tree has any lean to it (and it usually does have some), that affects the height measurement too. Imagine the time commitment involved in measuring all the significant trees in a forest stand. It can easily take a half-hour, often much longer, to deal with all the problems, and arrive at a precise calculation of the height of one tree.



Odd, zig-zag bark on old white pine
A forester would probably be happy guesstimating a tree's height, with accuracy to within a few feet. With Bob's mathematics and engineering background applying pressure, he wouldn't be getting much sleep at night if he worked to that paltry precision. And that's part of what's given Bob his ever-growing national (even international) reputation as the go-to guy for information about old and big trees. A very quiet personality belies the zeal that burns within. Few that I'm aware of can, or will, devote the time and energy Bob allocates to documenting and advocating for the largest cellulose-based living things on the planet.


Yellow Birch on captive boulder
Old Sugar Maple
Root tunnel
I think, for Bob, this all stemmed from a love of big, aged trees, and the sense of awe, timelessness, and even spirituality that you feel when immersed in the mountainous virgin forest haunts Bob frequents. It's quiet in those places, save for the wind in lofty boughs, or the sshhhhhhh of rocky brook cascades. You feel removed from the insanity of the world while you're among grizzled forest giants, their antiquity somehow encompassing you and making civilization irrelevant.

Moss everywhere
It's peaceful, soothing, and hugely therapeutic to backpedal in time in such a place... gnarly yellow birches with talons gripping boulders sheathed in velvet moss... ferns... rotting hulks of windthrown giants... glacial boulder fields half-buried in the leaf litter of thousands of years... spongy earth compressing under your feet... new life emerging from remains of yesteryear...

Here you know the cycle keeps going 'round, with no regard for time or the vagaries of men's purposes. Rocks, through eons, are gradually weathered down to soil; trees spring from it, have their days of glory, then crumble back into the soil that gave them life. On and on.
Eventually to be soil ...


 But there are other motivations that draw Bob and others to these forests too. Scientists are very interested these days in how much carbon a growing tree can lock up in its tissues. A towering white pine that a commercially oriented observer might categorize as "overmature" (and in need of harvesting) might appear to have stopped putting on new wood at its base. However, Bob and others have found that these trees are often adding huge amounts of new growth at their upper reaches, more so than in their basal circumference.

Bob is recording white pine heights of over 170 feet, an impressive feat for New England trees. To be fair, such heights are attained mostly in coves of steep, high mountains, where protection from wind is provided, and there's plenty of soil moisture. These coves are growing some really impressive specimens, including species such as maples, hemlock, white ash, oaks, yellow birch, and others. But so far, white pines are the New England kings when it comes to height.
Bob (left) teaching tree measurement class

An ongoing mission for Bob is to spread the word about the trees he cherishes to as many people as will listen. And listen they do. His encyclopedic knowledge and his enthusiasm are infectious. In his own words, "I'm obsessed". Many have had the good fortune of acquiring his obsession too. A day in the company of Bob and the big trees leaves you hungry for more.




Thanks largely to Bob's efforts, and those of other enthusiasts he's fired up, many stands of now-cherished big and old trees have been cataloged, and are being protected.


I look forward to a lot more opportunities to slog along mountain streams, to lose my breath clambering up rock ledges, and to learn much more about the old growth woods of western Massachusetts from Bob Leverett, the "Guru of eastern old growth forests". Oh-- and to the perennial chuckles we share quoting Monty Python lines on the way back to the car...  




Yellow Birch, streamside


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