Great Lakes
Sunrise at Sax Zim Bog. Getty Images.

MN - Bog is dead: The waning defense of Minnesota wetlands

What once captured carbon will soon release it

Early one Sunday morning my son’s Boy Scout troop toured a small research facility in the middle of the Chippewa National Forest in northern Minnesota. As the presentation began, someone handed me a chunk of wood.

Researchers sawed this simple round from a tree pulled out of a nearby bog. It was perfectly preserved, even though the slab turned out to be older than St. Edward’s chair, Christ’s cross, or even Noah’s Ark. It was certainly older than the European cities that produced my ancestors, the ships that carried them to America and the towering pines they cut down upon arrival.

How old was it?

No joke. Tests confirmed that this tree became entombed in the bog at least 5,000 years ago, preserved by tannins leached into the bog from cedar trees and other vegetation. This reminded me of all the ancient human bodies discovered in wetlands around the world. Some of them were as many as 10,000 years old, their skin and facial features unperturbed by time. Lead scientist Randy Kolka said it’s only a matter of time before we find similarly preserved human remains in the northland.  “They’re out there,” he said.

These finds demonstrate the preservative power of peatlands, including some of the continent’s biggest freshwater bogs here in Minnesota. These wet wonders don’t just preserve old wood and dead bodies. Swamps, bogs and fens capture vast amounts of carbon and have for millennia.

After the last Ice Age, wetlands formed from the recession of glaciers as inland seas transformed into land. Dense, nutrient laden soil captured pools of water upon which layers of peat formed year after year. Even as humans erected smokestacks across the globe, the mosses and peat of wetlands seized and stored carbon from the air.

And if that doesn’t interest you, consider that these peatlands are now poised to belch all that carbon into our atmosphere, tilting climate change from bad to worse in a matter of years, not centuries.

You don’t have to wonder what climate change might do to Minnesota’s forest ecology. At the U.S. Forest Service’s Marcell Experimental Forest, you can see for yourself. Here amid the sphagnum, tamaracks and black spruce, scientists built a fleet of time machines. Each will take you to the future.

Life in the bog

I grew up in the Sax-Zim Bog south of Eveleth. Theoretically, I could have communed with nature and the diverse populations of migratory birds. But in the 1980s my family ran a junkyard. Instead of all that nonsense, I pulled around a metal plate with four protruding bolts pretending it was a cat because our real cat was too mean to pet.

I liked to climb the earthen barricades of my family’s sharp metal playground. St. Louis County forced my grandfather to block the view of the junkyard from Highway 7 with long berms of gravel and swamp muck. He dug them with his backhoe, a dinosaur in the mire, creating a small, shallow lake skimmed with oily rainbows and doomed frogs.

Like Sisyphus, I tried to protect the frogs to no avail. The tadpoles didn’t last long in fish tanks, especially when you fed them French dressing from the school cafeteria. When the vernal pools under the berms began to drain, the tadpoles and young frogs became attractive snacks for crows and snakes.

Out past the gash my family cut in the swamp unfurled the real bog: mossy and foreboding. My mom cautioned my sisters and I not to play out there. We ignored her, usually sinking thigh deep in muck while fleeing clouds of angry ground hornets. Bogs can be scary. Author Annie Proulx captures that feeling in her 2022 book “Fen, Bog, and Swamp: A Short History of Peatland Destruction and Its Role in the Climate Crisis.”

“Suspense writers find bogs very useful,” Proulx writes. “Bogs stir fear. They are powerfully different from every other landscape and when we first enter one we experience an inchoate feeling of standing in a weird transition zone that separates the living from the rotting. Black pools of still water in the undulating sphagnum moss can seem to be sinkholes into the underworld.”

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