Tag Archives: Forests

Young Scientists Plot for Smart Urban Forestry

by Liz Brownlee

“Wait until you see the accuracy of our plot,” calls the lab team.

The four undergraduates burst with pride, oblivious to the prickling raspberries and thick brush that edge the Intervale forest.

They stop me midstride.  As their lab teacher, I’m fully equipped with aerial maps, GPS, first aid kit, phone, and extra rain gear.  I’m planning to cruise through this pasture towards the soybeans and into the swampy forest.  My goal is to check in with teams at twelve more study plots, spread over the 350 acres of forest and fields.

This lab project is a real, on-the-ground application of their natural resource training.  Most weeks these first-year students learn the basics of field work in big, broad fields (fisheries, stream ecology, forestry, etc.). The field data they record in their weekly labs is important: they use it to learn how to create papers, reports, and essays.

This week, though, the data is headed to city hall.  We’re studying the Burlington urban forest to help the city make informed decisions about valuing and managing the forest.

I need to check in with the next group. It’s incredibly important that the teams describe each plot with accuracy and efficiency.  I know that all the teams are anxious to prove their worth, to share their budding knowledge and field skills.  But this team’s stories cannot wait.

Elliot, a bright-eyed skier from Utah starts first.

The maple we used to mark our plot was so big, our measuring tape couldn’t reach around it, he says.

Aptly named and observant, Hunter chimes in.

There was a deer trail, but that’s it – otherwise it’s untouched.

Eric, a tattooed, intelligent former Marine, knows this isn’t entirely true.

How should we record the land use on this plot, Liz? This isn’t a park, and it’s on the farm but not cultivated land.

We brainstorm the forest’s values: recreation and flood control top the list.

I change my route, unable to leave the pull of their enthusiasm.  Elliot fires questions as we walk the farm’s puddle-filled gravel road.

We didn’t see any sign of invasive species like emerald ash borer – that’s good, right?  And the ground was covered in mud from the hurricane and the flood – do you think the forest will rebound before teams come next year?

The team answers most of their questions before I can chime in, and I know that I’m no longer needed.  I head for the next site when Carly, another lab teacher with twenty more students, calls from the Old North End of Burlington.  We check in, cars honking in the background on her end.

Over two hundred UVM students are taking the pulse of the forest, from tree height and canopy dieback to ground cover and plant-able space. They’re studying over one hundred plots throughout the city, and all in just two weeks.  We’ll crunch the numbers with a program called iTree that’s being used worldwide.  The city will use the results to decide where and what to plant next, and how to properly value a forest that cools homes, mitigates pollution, and absorbs storm water runoff.

They’ve tracked changes in the forest’s health.  They’ve built confidence as budding natural resource scientists.  And next year, two hundred new students will do it all again.

A Bypassed Giant

by Rachel Garwin

What’s the last amazing thing you overlooked?  I discovered mine last Wednesday in Centennial Woods, a 65-acre natural area near the University of Vermont campus.  A friend and expert naturalist was

white oak sketch

White oak sketch.

sharing his local knowledge with a group of undergrads, and I had tagged along.  The familiar path turned to the left in front of me, but I looked at the woods beyond it as if for the first time.  Gore-Tex dripping with unseasonably chilly rain, I stared unbelieving at the biggest white oak I’ve seen in Vermont.  A white oak I’d never noticed before, despite passing it scores of times in the last year.

Its whitish, ridged bark transfixed me, and I longed for the warmer conditions favored by this southern species.  I heard my friend estimate its age around 300 years, but how could that possibly be?  Too soon we walked away; commitments required our presence back on campus.

For the rest of the week, the white oak filled my thoughts.  My wonder pulled me back to the woods on the crisp, clear Saturday that followed.  I marveled at the oak itself, but also looked at the forest around me with new eyes.  Had I been asked to describe the patch a week before, I would have shared my general impressions of Centennial Woods: a weedy jumble of pioneer trees—red maples, paper birch, white pine—and invasive shrubs that grew up after field abandonment at least sixty years ago.  Now I wasn’t so sure.

White oak acorn caps, © 2011 Rachel Garwin

White oak acorn caps.

Instead of that theoretical assemblage, hardwoods covered the hillside above me. Red maples’ old, platy bark and smooth, young trunks textured the forest, spotted here and there with gargantuan, grooved-barked white pines.  The occasional pines shot straight into the canopy, towering above the broadleaves glinting yellow-green in the sun.  Instead of poison ivy—a scourge on the rest of Centennial Woods—intermediate wood fern and sensitive fern carpeted the duff-covered ground.  Sun flecks danced across fern and leaf alike; their shimmers added another lively layer atop the chatter of insects, blue jays, and red squirrels.

flaky oak bark, © 2011 Rachel Garwin

Up close, the rough, ridged bark is surprisingly flaky.

Cool air washed over me.  I thought of the jacket hanging on the newel post at home, but resisted the impulse to run after it.  Instead, I hopped off the fallen pine and wrapped my arms around the oak, fully two wingspans around.  Rough, flaky bark pressed into my cheek as I looked up along the trunk.

The spreading crown of layered branches dominates the sky.  The branching pattern differs between the lower and upper trunk: until the tree rises above the neighboring red maples and rotting white pines, branches grow only on the southeast side of the oak.  Once free of competing limbs and leaves from other trees, however, the branches radiate in 360 degrees.  Since branches in high light environments have more access to abundant energy, they grow more quickly—and are more likely to survive—than branches in shady environments.  Once the oak’s top emerges from beneath the canopy, however, its branches have equal energy opportunities and reach in any direction.  It follows, then, that this tree grew up on the edge of shady woodland to the west and north, much like the present patch of woods is situated today.

I walked around the massive trunk, careful of roots and uneven ground.  The barbed wire took me by surprise.  Extending from the very center of the tree, the rusted, twisted strands extended east-northeast.  I imagined the wire extending into a fence running further northeast and southwest, through the center of the oak and perpendicular to the growing direction of the lowermost limbs.

barbed wire in white oak, © 2011 Rachel Garwin

Rusty barbed wire protruding from the base of the white oak. The design looked similar to the common Glidden “Winner” variety patented in 1874 and widely available across America.

These waist-thick protrusions of wood would have reached towards the sun-rich pasture across the barbed fence, growing massive.  Today, however, the lowest branches are dead.  When they fall, the trunk will grow around the branch scar, resulting in a large burl.  Lower branch scars exist, but none as striking as what the future holds.  Does this lack of gigantic burls suggest that yesterday’s lower limbs were smaller?  Did the oak originally grow in less sunny conditions on that side, which reduced the amount of energy available to the tree to create huge branches?  Or had the tree simply been younger and smaller, yet unable to produce such girth?  Regardless, the branching pattern suggested that the patchy area to east and south—now growing with young, even-aged, forked white pines—was once open.

My friend claimed the oak was 300 years old, and I’d believe him based solely on the tree’s size.  The oak’s stately bearing is convincing as well.  The spreading canopy still bears a lush complement of waxy, dark green leaves; 300 can be considered middle-aged when oaks have been known to live as long as six centuries.  A relatively fresh acorn cap lay at the ground, however, suggesting the tree is still of reproductive age, or between fifty and 200 years old (though sometimes older).  Without coring the oak, we will never know for certain, and the mystery will continue.   How had I missed it so many times in the past?

fallen oak leaf, © 2011 Rachel Garwin

A freshly fallen white oak leaf lying among bits of old pine needles, maple leaves, and bark chunks on the forest floor.