September is the Best Season to Explore Wild Places

There’s never a bad time to be in the Boundary Waters Canoe Area Wilderness in northern Minnesota (although peak black fly season comes close) but in my experience, September is the best. Likewise, there’s never a bad part of the Boundary Waters to visit, but the big water of Snowbank Lake and the smaller lakes beyond are particularly interesting. 

Large-leaf aster is just that for most of the summer—big, heart-shaped leaves covering almost every inch of ground along the portages and campsites. All the leaves in a patch are likely connected by horizontal underground stems called rhizomes. If you’re patient, the ones who’ve received enough sun flecks through the tree canopy will finally send up a tall stem topped by pale purple flowers in late summer. If you’re really patient, the flowers become dry seedheads that persist through the winter as pale, straw-colored versions of the blooms. Not everything has that kind of staying power. 

Mushrooms also line the portages in late summer and fall, so if you lean over to smell the asters, you might end up with a big whiff of fungus instead. The odors they produce as they melt into goo are rarely just byproducts of decay. Instead, fungi produce volatile organic molecules (VOCs) to serve a purpose. Some fungi try to attract insects. At one end of the spectrum, smelling like carrion attracts flies and beetles who may land on the mushroom expecting rotting meat, and then carry spores off to a new place. At the other end, smelling like flowers may trick pollinators into doing the same thing. Sulfurous stenches might repel potential predators like slugs, mice, and humans, so that the mushroom has time to mature. And some smells might even waft over to another fungi and inhibit their growth. They certainly inhibit my desire to stand nearby. 

A glacial erratic looms as we paddle by on Disappointment Lake, its reflection shimmering on the calm water. Bigger than a car, this huge boulder was picked up by glacial ice, carried for a distance, and then dropped on a spruce- and juniper-covered point where it doesn’t match the bedrock. The rounded corners of the rock tell us that it was jostled and worn down during a lengthy journey. If a scientist scraped off the lichens, mosses, and ferns that sprout from its surface like fur, they could perhaps match the erratic to the bedrock of its original home and discover something about the glacier’s path. Glacial erratics are sprinkled like confetti across the Northwoods, reminding us of the youthful nature of this landscape post-glaciation. I chart our path on my map, heading toward a small x marked with a pencil several years earlier. 

The metagraywacke doesn’t loom, instead it slopes gently out of a back bay as a wave-worn shelf. The ease of the landing, the smooth rock’s invitation to lay out in the Sun for a while, these are the privileges of respite earned after millennia of action and violence. The landscape here may be young in geologic time, but the ancientness of the bedrock is part of why I feel grounded when visiting. 2.5 million years ago or so, this region was a volcanic arc in the primordial sea. Earthquakes shook the volcano and sent loose sediments tumbling downslope in underwater landslides. Each time the sediments tumbled, they came to rest in the same order: heavy rocks first, then smaller grains of sand, and then fine bits of clay. When the volcano shook again, the process started over, with big rocks landing on top of the clay. Fast forward through being buried, turned to rock, metamorphosed, turned on its side, unearthed by glaciers, and smoothed by waves, and we can now read history of this bedrock in stripes formed by pebbles, sand, and clay. The artistry of windblown clay is our next stop…

Desert varnish streaks down the sloping outcrop as we bob below in our yellow canoes. This is no desert of course, but windblown clay, iron, and manganese stick to damp rock just as easily here as in my favorite canyons in Utah. Wet spots glisten and vibrant moss glows green along the top of the cliff where the black coating is constant. Near the bottom of the cliff, where the original, pale bedrock shows through, crusts of orange lichen add splashes of color. It’s beautiful. And then, a few red smudges catch our eyes. Is that a handprint? A stylized canoe? Nature isn’t the only one who paints on these rocks. 

Three young common mergansers startle off their napping rock in a jumble of quacks and splashing. Their gray bodies and cinnamon heads look similar to their now-absent mother, but smaller crests, more white on their faces, and a thin brown stripe extending back from the base of their bills tell me that these are the young of the year. They may have started the summer with a dozen or more siblings, but the phrase “safety in numbers” simply means the extras are the ones who get eaten, not you. Since we disturbed their nap, the mergansers dive back in for some fishy snacks. 

The smell of frying fish is a major asset to any canoe trip, but since I don’t share the merganser’s skill as an angler, I usually miss out. For this trip, I brought both a fisherman (my dad) and a camp chef (my mom). The hot, crispy fillets they add to my plate will give me enough energy to portage their canoe as well as mine. I think it’s a good trade. 

A young loon greets us on the far side of our final portage. We battle the wind as they bob contentedly on the whitecaps. They look comfortable now, but what about in November when they finally fly south? I wonder if their flight muscles will get as sore on their twice-a-year migration as our paddling muscles get on our twice-a-year expedition. 

In my ideal world, the solution to sore shoulders would be to get up here so often that my muscles become as tough as all those rocks! 

Emily M. Stone is a naturalist by birth, training, profession, and passion. She explores the Northwoods with an eye toward using science to make stories come alive.