ShareThisCENTER SANDWICH, N.H. - The second-biggest sugar maple in our south pasture is dying. Thick stubs of broken branches poke the sky. Along the stonewall, another tree, one I've tagged as Tree 801, has had large pink patches of fungus growing on its trunk. Bark is falling off. On the north field, a very young tree, with a trunk just 6 or 8 inches wide, produced so many flowers last spring that its buds had no room for leaves. Its branches were naked all summer.
Climate change is projected to kill all of my sugar maples and most of the sugar maples in the United States by 2100.
"Over my dead body," I told Barrett Rock in 2007.
Rock, a professor at the University of New Hampshire, took me on as a student. I am studying sugar maples, wood anatomy and physiology, and climate change at the university's Natural Resource and Earth Systems Science program.
Most of the maples on my farm just south of the White Mountains are robust and healthy. At the university I am learning how to take the pulse of these trees, to measure the first touch of stress and ill health.
I've used the scanning electron microscope to photograph a snow flea at 500x, turning a bug the size of a grain of rice into an extraterrestrial monster. At 342x, maple xylem cells look like the sacred niches where Buddhas once stood in Afghanistan.
The visual infrared intelligent spectrophotometer (VIRIS) measures light reflected from my samples of maple leaves. Images of the forest canopy captured by Landsat, a satellite flying over Earth at 500 miles up, measure the same light. If I learn how to read leaves in the laboratory, we might be able to interpret messages about large groves of trees all over the sugar maples' range.
High-tech tools need simple field measures to support whatever laboratory measures may claim. Once a month, I visit my tagged sugar maples. I collect leaves, photograph their color, measure their size, note when they change color in the fall and when they fall off the tree.
My first VIRIS measures in 2008 showed that leaves on 30 trees collected on five sugar bushes in my valley were all stressed for water and all had less-than-normal amounts of chlorophyll.
"This tree is really stressed," Rock said, scanning one of the light waves I captured from Tree 812.
My simple field measures told the same story. The maple leaves curiously grew smaller as the summer progressed. Big expensive leaves were dropping off in August and early September to save smaller, more efficient leaves. Whole trees never made it to fall foliage season: Their leaves turned mousey brown and dropped off, chewed ragged by insects and spotted with fungus, in mid-September.
The summer of 2008 was typical of the new weather patterns that climate-change scientists forecast for New England. From leaf-out in late April to late June, we had no rain. It was the driest spring on record. Then, from late June to mid-August, torrential rains turned my gardens into mud. The trees were stressed.
Then spring 2009 came. My husband, Rudy, and I tapped our maples. Right from the get-go, our syrup was much darker than usual. The sap filters were black with gooey sugar sand we usually see only late in the season.
I carried sap samples to the university and went from lab to lab looking for a biochemist who could assay the liquid to see what was causing the darkness in my syrup.
Walter Shortle took me on. This spring he and I will assay sap samples from sugar bushes all over New Hampshire. And in the summer, I'll measure leaves from those same sugar-maple groves to check leaf size, leaf color and VIRIS scans, looking for signs of stress.
I am the citizen scientist, the person out in the forest who collects leaves and notices small changes day by day. Part of my study will be finding more citizen scientists and training them to help us.
(Reach Martha Carlson at rmcarlson(at)ncia.net. For more stories, visit scrippsnews.com)
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