Sharp Eyes

Winter often brings moments of delight when clean drifts of snow become the canvas for nature’s artwork. If not lost in the tunnel of my thoughts, I might notice the shadows of twigs making purple lace across the white or the detail in a papery seed or frost-lined track. Sometimes it helps to have a friend along to make their own unique observations.

Earlier today I began digging through folders to find photos of those winter delights. Soon I’ll share them with local artist Janet Moore’s “Wheel of the Year: Four Seasons” class. This virtual class will be meeting nine times over this coming year to create a unique piece of art chronicling the seasons in your own woods.

Janet Moore's sugar-maple-themed Wheel of the Year. Course info here. 

Just outside my office door, coworkers were exclaiming about delights of a different kind. A generous Museum member has given us a few boxes of old books. I expected the nature guides from the 1950s, and big stack of Sigurd Olson’s books, but mixed in with those were cloth-bound covers with shiny gold lettering and copyrights dating back to the 1800s.

I lifted one off the pile, enjoying the texture of the midnight blue cover and the history implied by frayed corners. Sharp Eyes gleamed in gold. Was this a story about far-seeing raptors? Or hyper-focused wolves? Inside, the subtitle gave more clues: “A Rambler’s Calendar of Fifty-Two Weeks among Insects, Birds, and Flowers.” So this was a book about phenology—the study of when specific events happen in nature from year to year in a specific place. The short chapters and black-and-white illustrations reminded me of my own Natural Connections books.

As I skimmed the introduction, a sentence caught my eye.

[Sharp Eyes is] “a cordial recommendation and invitation to walk the woods and fields with me, and reap the perpetual "harvest of a quiet eye,” which Nature everywhere bestows; to witness with me the strange revelations of this wild bal masque [masquerade ball]; to laugh, to admire, to study, to ponder, to philosophize between the lines—to question, and always to rejoice and give thanks!”

I chuckled a little at the verbose style of the era, but felt a kinship with the author nonetheless. We write in the same genre, and with the same purpose. I took the author up on the invitation, but who were they?

Skimming past a few more rambling pages, I found his signature at the bottom: W. Hamilton Gibson, Washington, Conn., July 10, 1891. Quick research told me that Gibson’s father’s death forced him into gainful employment as an insurance salesman, but that lasted less than a year before he turned back to writing about and illustrating nature. I can’t say I blame him.

With a glance to the snowdrifts outside my window, I flipped to the last section of the book, where a whimsical version of WINTER endured a blizzard on the page. How would Gibson’s observations in western Connecticut compare to mine?

WINTER section heading by W. H. Gibson from his book Sharp Eyes.

“But both boys and girls may well put aside their sleds for a walk with me this morning,” wrote Gibson. “This snow is good for something else than coasting…” Oh is it now, I chucked, thinking back to how much fun I’d had writing about the natural history of sledding.

“Those who like a good story-book will do well to study the snow, for they may indeed read it like a book. It is a great white page storied with the doings of the little wild folk which few of us ever see.”

by W. H. Gibson from his book Sharp Eyes

I nodded in agreement, thinking of the many photos of mouse and bobcat tracks that now filled my folder for Janet’s class, and the wolf tracks still visible on my driveway.

“They write their autobiography day by day…but they are not responsible for all the singular hieroglyphics to be seen on this great white page. The wind often takes a hand, and after a light, fresh snow-fall plays pretty pranks with the drooping stems of some of the withered grasses.”

Last winter I struggled to find something kind to write about the gray squirrels that attacked my bird feeders, but Gibson had no such prejudices, and wrote,

“On almost any genial day we are sure of him if our eyes are sharp enough, and our manners sufficiently decorous…Let us observe our squirrel carefully. There he goes in graceful bounds across the snow, his sensitive plumy tail in every movement expressive of its homage to the line of beauty.”

After that I had to set the book aside and tackle other projects. But this was a happy moment of connection. I know I’ll join Mr. Gibson on another walk again soon. This blue-coated man with gold trim will be a friend who will help me make unique—if also longwinded—observations through all four seasons.

Gibson illustrated his own books in great detail, including this sketch of the bracts of birch catkins on the snow. Illustration by W. H. Gibson.

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

Wolf!

I love coming home.

It’s not those feelings of comfort and familiarity I’m looking forward to, though. I’m eager to see which of my many wild neighbors have walked down my driveway!

An inch or two of snow on top of the last pass of the plow truck provided excellent tracking last weekend, and big tracks quilting the median had me bouncing in the driver’s seat. After parking, I walked back to investigate. There, within a few dozen feet of the house, I spotted the first tracks. Four toes. Claws. Roughly the size of the palm of my hand. Could it be? This would be a first for my yard…

Wolf tracks are roughly 4 inches long and wide. Coyote tracks would be closer to 2.5 inches. Photo by Emily Stone.

The animal tracks disappeared under my wheel tracks, and then reemerged—still within sight of the house. Four toes. Claws. Roughly four inches long.

I was forming a guess in my mind—a hopeful identification of my new neighbor. Do you have a guess yet?

Wolf!

Northern Wisconsin has hundreds of wolves. The DNR’s maps of wolf packs show a dense mosaic of territories. Neighbors to the east have had wolves on their trail cams. I’ve seen tracks just two miles south of my house in the Chequamegon-Nicolet National Forest, and on all of the ski trails I frequent. But, ever since I moved in 11 years ago, the general wisdom was that the high density of homes, resorts, and activity around Lake Namakagon was too busy for wolves.

Of course, in nature, saying “always” or “never” is a tricky business.

As I followed these tracks back out of my driveway, they wandered in and out of the wheel tracks and back and forth across the median. By the time they led me directly in front of my trail camera, my head was buzzing with excitement. Of course I grabbed the memory card. Shadowy figures appeared in the dark photos, looonng legs trotting and tail relaxed. This semester I’ve been teaching 3rd graders how to identify a wolf and a coyote, and there was no question in my mind who this canine was!

My trail camera captured this wolf as it walked out of my driveway after taking a nap in the woods. Photo by Emily Stone.

At 9:22 p.m. a wolf walked into my driveway. At 2:01 a.m. a wolf walked out of my driveway. And then, 12 seconds later, another wolf! The tracks were messy enough that I’d been suspecting more than one animal, but this was my first real proof.

At the end of my driveway I found the snowbank sprayed with yellow urine at about the height of my knee. Wildlife biologists and trackers call this an “RLU,” short for raised leg urination. This is a form of scent marking—the sign of a wolf claiming his territory. Female wolves also scent mark, but are more likely to squat when they pee, and the mark appears lower down. There wasn’t a paired RLU here, though—no evidence of a female joining in. What does that mean for the relationship status of these wolves?

Next, I went back to the place, just out of sight of the house, where the wolves had wallowed through the snowbank and into the forest. Strapping on snowshoes, I followed.

Over logs, under balsam thickets, and past a frozen wetland we traveled. Numerous trees had been sprayed with yellow. Wandering, dispersing wolves tend not to scent mark. If they are just exploring or passing through, there’s no reason to waste energy claiming space for their own or risking discovery by another wolf who is willing to defend their territory. This many RLUs most likely means that these wolves are planning to live here and want to deter any rivals from intruding. I might be seeing evidence of these new neighbors again!

Where did they come from, I wondered? Wolves have been known to travel over 500 miles to find a new territory, but the density of wolf packs nearby suggest that a recently matured wolf may have simply budded off from his natal territory, found a quiet corner of the forest nearby, and befriended another loner for company, or in the hopes of being able to breed.

Finally, only a tenth of a mile from my house, under a balsam thicket, were two icy bowls in the snow. The warm body of a wolf had rested in each, compressing and melting the snow. From the trail cam, I knew that the wolves had passed through on a night when the temperature plunged. They might have sought this protected area, on the south side of a hill and under conifers, to take a five-hour nap in the bitter cold.

I was thrilled to find two icy wolf beds at the end of their tracks. Wolves simply curl up on top of the snow. They only spend time in a den when having pups. Photo by Emily Stone.

Tracks led into the beds and then back out, retracing their steps all the way back to my driveway. Where they went from there is anyone’s guess. I couldn’t pick up the trail again after they hit the road. I’ll be watching for them, though. I’m hopeful that my woods are part of their territory now, and (like me) wolves seem to enjoy coming home.

The wolf's RLU and my Private Drive sign in the background are essentially saying the same thing to our own species! Photo by Emily Stone.

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

Least Weasels in the Subnivean Zone

Sometimes, when temperatures struggle to rise above zero, it takes all of my willpower to get out for a simple walk. Even when cheeks sting and the ice in my eyelashes sews up the corners, I know that getting outside will do wonders for my mood. When possible, I do try to plan any outdoor excursions for “the heat of the day.”

So it was noon on one of those bitterly cold days by the time I wrapped up some cookie baking and clomped down my driveway. Coyote tracks quilted the snow between the tire tracks, but they were softened by time and flurries. Nothing new.

And then, there was something new! Several pairs of tiny tracks stitched a line across flat ground and up the bank before disappearing into a hole no bigger than one gloved finger would poke under a mess of dead branches. Each set of prints could have fit on a nickel. In a few places, parallel lines connected the tracks to each other as the critter’s jump didn’t quite rise fully above the snow. Any signs of tiny toes were obscured within the texture of snowflakes.

Tracks of a least weasel disappear into the snow—into the subnivean zone.
Photo by Emily Stone.

“Least weasel!” I exclaimed before taking a few quick photos. Then my phone died from the cold.

With a maximum size of 8 inches long—including tail—least weasels are the smallest weasels in Wisconsin. Female weasels are smaller than males, tending toward 6.5 inches long, and weighing only 37-40 grams. Small animals tend to lose heat quickly, because of their large surface-area-to-volume ratio, so it’s odd that the smallest of the dozen or so least weasel subspecies lives in northern Russia, and the largest lives in North Africa.

There is one major benefit to being small in winter, though: least weasels can fit easily into the narrow passages and tight spaces of the subnivean zone. Inside this magical space where ground meets snow, a crystalline blanket traps the earth’s warmth, and temperatures hover near freezing. The subnivium is so important to Mustela nivalis, that their scientific name means “weasel of the snow.”

Earlier that morning, when the air temp read -13, my thermometer buried under just 6 inches of fluff registered a balmy 28 degrees. Being small means that the least weasels almost never have to venture up into the frigid, windswept winter world.

In fact, their entire body is designed to exploit the underground. A narrow head, lithe body, short legs, and flexible spine allow weasels to maneuver easily in tight spaces. Sensitive whiskers and a great sense of smell guide weasels in the darkness. They don’t dig their own tunnels, but then, why would they? Mice, voles, and chipmunks can be found in the dens they’ve dug themselves—in either snow or soil.

With a bite to the neck, least weasels are even able to take on adult rabbits—prey that is at minimum 16x bigger than this feisty little predator. In fact, least weasels are the world’s smallest carnivore. When relaying this fact, I’m often asked, “What about shrews?” Shrews are insectivores, and members of the now-obsolete taxonomic order Insectivora instead of the weasel’s order of Carnivora.

Unlike wolves—another member of Carnivora—who often gorge on a kill and then go without eating for several days, weasels cache their prey and come back for smaller snacks 8-10 times each day. To feed their fiery metabolisms, weasels eat at least half of their own weight daily, and more in the winter.

Least weasels are prey as well as predators, and they attempt invisibility by transitioning from summer brown to winter white fur. Unlike their cousins, the short-tailed and long-tailed weasels, least weasels do not keep a black tip on their tail. In the larger weasels, that bit of misdirection tricks raptors into aiming for the wrong end. In least weasels, their head and their tail are just too close for comfort.

Least weasels change from brown fur in the summer, to all white in the winter.
Photo by Cecil Sanders, flickr.com.

Speaking of comfort, I found myself a bit jealous of the “weasel of the snow” today as I ventured into a sparkling, -21-degree morning. While my car and lungs protested equally at being asked to work in such conditions, my subnivean thermometer had risen to 31 degrees under the added insulation of a fresh foot of snow.

I probably won’t have another chance to see tracks or sign from my tiny neighbor this winter. At least I know that they are staying warm under the snow as I imagine their adventures in the subnivean zone.

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

The Multi-Species Fun of Sledding

The purple shadows of evening were sliding out as I pulled into the driveway. After tossing my backpack inside the front door, I snugged up the hood on my puffy coat and grabbed the blue plastic sled from its corral behind the bike rack. The first run was slow, as fresh, fluffy snow compacted beneath me. I stomped up the trail and launched again, this time gliding a few feet farther; my heart feeling a few ounces lighter.

My sledding hill isn’t very big, but I do notice that playing on it does release stress and tension at the end of a day. Photo by Emily Stone.

I’ve always loved sledding. Maybe it has to do with my January birthday, or the thrill of going fast (but not too fast), or even the laughing chaos of a tumbling crash. Once I became an “adult,” I would wait until Christmas break when I could use my niece and nephews as an excuse to play in the snow. But after finding a sled in a free pile on a curb last spring, the only excuse I need is to be already wearing snow boots and ski pants.

Last week, while researching play in young animals for our new Growing Up Wild exhibit, I happened across something interesting: sliding down hills is one of the more widespread forms of play, and one of the types of play reported in adult animals, too!

River otters are the classic sliders. I’ve followed their tracks for miles as they scampered up the short, steep banks of a lake, only to launch themselves back down. Even on flat ice, they will propel themselves along the slippery surface. Can we blame all of that playfulness on the juveniles? I doubt it.

Otters are one of several critters who enjoy sliding on the snow, even on the flat surface of a lake! Photo by Emily Stone.

The snowy home of polar bears is conducive to sliding, too. One bear was observed cascading off a glacier, dropping fifty feet into the water, and then climbing up to do it all over again. Smaller hills—including the furry summit of Mom’s back—are also fair game for bear cubs.

Ravens and crows have been caught on video rolling down snowy car windshields, rooftops, and more. Like (college) kids sledding on trays smuggled out of the cafeteria, one crow in Russia made do with a white jar lid. With pokey feet resting on the slippery lid, and wings flapping madly for balance, the crow made run after run down the neighbor’s rooftop. No need for a chairlift, the crow picked up the lid in their beak and flew back to the peak.

Since wild animals slide down snowy hills, and likely have been doing that for millennia, the human history of sledding probably goes back pretty far, too, right? It’s hard to tell. The use of sleds for practical purposes can be confirmed all the way back to 1900 B.C., through paintings depicting rocks being pulled on sleds toward pyramids under construction. In the Cimbric War of 113 B.C. some Germanic tribes surprised Roman warriors by sledding out of the mountains on their shields. It's hard to believe that kids during these eras never saw the grownups using sleds for work, then nabbed one to race down a hill for fun.

Of course, childhood was probably shorter and less fun back then, especially for the working class. In contrast, the youth of Russian aristocrats in the 1650s seemed to have sledding backwards. They made their sleds from blocks of ice, and their chutes from wood!

In the United States, sledding became mainstream when farm equipment manufacturer Samuel Leeds Allen patented the steerable Flexible Flyer in 1889.

Animals slide and humans sled, ski, and snowboard, but my next question is WHY?

Multiple experiments have confirmed that playful young are more likely to survive to adulthood. Despite many hypotheses, however, scientists haven’t been able to prove the mechanisms behind how play increases survival rates.

There are some interesting clues, though. Play might allow young to test, learn, and stretch their own limits and abilities. Creative play seems to encourage brain development. The motor skills and physical fitness developed during play may improve animals’ ability to escape predation. The short-term stress of play might also give the animal’s stress response practice in recovering quickly after an incident. Could being startled in a game of peek-a-boo make being startled by a predator easier to recover from when the danger recedes?

Even in adults, it’s likely that play can release tension, improve the immune system, and ward off disease. What do you say to that?

I say wheeeeee!


Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is now available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. The Museum is now open with our exciting Mysteries of the Night exhibit. Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

Fragile Threads

By Guest Writer JoAnn Malek

[JoAnn Malek is a long-time Museum member and a recent participant in the Natural Connections Writing Workshop. JoAnn has graciously fine-tuned an essay that she drafted during that class. It touches on realities we all must face at some point—for ourselves and our loved ones--and I’m excited to share it with you this week. –Emily Stone]

Our morning hike began on a steep downhill sidewalk laden with wet leaves, squished Osage oranges, errant branches, and jutting rocks. I was wary and careful, glad to have good eyes, new walking shoes, and sturdy trekking poles.

The trees above were lush, with leaves in more shapes, sizes, and greens than we find in a Wisconsin woods in October. Rocky ditches and muddy gullies carried trickles of water, a reminder of how this ridged, deep-valleyed hill country was formed. Raptors were using updrafts, soaring in the blue, but a bank of dark clouds was spreading across one section of sky. My rain jacket was at home.

The author admires a tree during her visit to Arkansas last October. Photo by N. Deegan.

I had been touched to be invited along on a daughter’s family vacation. After several years of self-sufficiency, I was pleased to take a back seat for the trip through five states. My son-in-law brought two mountain bikes, to be used for different kinds of riding, apparently. This was a recreational mecca, after all. Grandson, daughter, and I packed hiking boots.

We continued walking into the Razorback Regional Greenway and emerged onto a flat sidewalk centered with a yellow line. I stayed far to the right, hoping my failing ears would perceive the approaching whirr of tires and the “on your left” warnings. Paths into the forest beckoned, but not for those without wheels and helmets.

Motion filled the woods. Riders leapt over hills, swerved around bermed corners, plunged down rock ramps, and roller-coastered through bumps.

Muscular adults peddled high-tech bicycles. There were daring, invincible teens, of course. But also small legs pumping, and mini wheels spinning. Parents carrying young ones. A group of young men in overalls, accompanied by young women and little girls wearing long skirts and lace caps. Teachers trailing school children. Even old women like me were riding.

There was much to watch as we walked, but I stopped short when an orange-spotted spider appeared just in front of me, hanging by a long, long thread. Thick ivory legs, a round ball of a body, and those pretty orange circles helped me identify Araneus gemmoides, a cat-faced or jewel spider. This species occurs throughout the Western U.S., including the Midwest, but I’d never bumped into one before.

Funny, but I found myself identifying with that brave, dangling thing. My long-time motto comes from Eleanor Roosevelt: “you must do the thing you think you cannot do.” I agree to adventures and accept challenges. That’s how I ended up on this tangle of trails in Bentonville, Arkansas. The spider had left the safety of the tree as I had left the safety of isolation from Covid-19.

At home, I care for a cabin and much that surrounds it, haul logs, tend a wood stove, and drive short and longer distances. I kayak, swim, hike, skate, and ski alone. The spider wove the thread that held her. I’ve woven one, too. Now we both cling to our independence.

When Jim became ill, our plans and dreams were cancelled. After his death, it seemed I’d been given another chance. But I had learned that any type of misstep can change everything. I’m fragile and vulnerable, like that eight-legged dangler.

Abruptly, a passerby severed the long thread. The spider fell gently to the ground and scurried away. Her journey had been altered. I expect that the threads connecting me to cabin life will one day be severed. Will that happen when it is no longer safe for me to drive? Will the aches and pains of an aging body prevent me from completing required tasks? Will an accident interrupt this life permanently?

I know, for now, that I can trust myself, but I must trust others as well. My children are watchful, always aware of my capabilities. They will help me continue to live in my happy place for as long as possible. When the thread of independence finally breaks, they will help me to move gently on to the next phase of my journey.


For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. The Museum is now open with our exciting Mysteries of the Night exhibit. Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

Snowflakes: Growing Up Wild

Snowflakes whirled outside my office window, blanketing the rainstorm’s aftermath in white and distracting me from work. Looking back down, I tried to focus on my screen, where the words Growing Up Wild sat above a rudimentary diagram of the Museum’s exhibit hall.

Ideas are coming together for our new exhibit, scheduled to open in May 2022. We’re excited to explore the many different ways that Northwoods critters begin, grow, survive, and eventually become adults. It’s fascinating to compare and contrast the life cycles of bears, butterflies, bluegills, eagles, humans, and more. Each critter takes their own unique path through the adventure of childhood, and it can be fun to imagine ourselves in their shoes.

Gazing back out the window, it struck me that the dancing snowflakes also grow up wild. Just like each of us and the other critters, snowflakes must begin somewhere, and then be shaped by changing circumstances at each moment of their development.

By Unknown author - Popular Science Monthly Volume 53, Public Domain, https.commons.wikimedia.orgwindex.phpcurid=15208176

How does a snowflake begin? In the sky, individual water molecules float suspended among molecules of air. Although temperatures may be well below 32 degrees and what we think of as the freezing temperature of water, the water vapor won’t freeze without help. Help comes in the form of ice nucleators around which the water can assemble into the crystal structure of ice.

Bits of dust and soot can become nucleation sites, and scientists are also discovering the importance of airborne bacteria. In particular, some bacteria have surface proteins that look a little bit like ice crystals. The protein template makes it much easier for water molecules to snap into place and begin the freezing process.

Why would a bacterium have evolved this trick? Well, these microbes need their ice-forming powers to access food. When on the surface of a leaf, the sharp edges of the ice they cause to form cut into the plant’s cells and spill juicy nutrients into the bacteria’s waiting arms.

On a windy day, though, those bacteria might get scooped up into the upper atmosphere. High above the Earth, the bacteria are cold, dry, and hungry. They need to get back down, but they are too light to fall on their own. Here’s where the ice-nucleating protein comes in handy again. The bacteria gather water molecules around themselves and form snow crystals.

Like tiny ballerinas, the crystals float across the sky and dance back down toward the Earth. The wind-tossed path that each crystal takes as it grows, and the conditions it encounters along the way, are what make each snowflake unique.

The first form that snowflakes take is a hexagonal prism with six facets, plus top and bottom basal facets. This shape is a result of the crystal structure of water, or the way the molecules line up when it forms a solid. How that crystal grows is a result of slight shifts in the temperature and humidity the flake encounters as it travels.

For example, when a snow crystal spends time in an area with low humidity, that promotes flat surfaces to grow. It’s easier for the sparse water molecules to latch onto thin, rough edges than a smooth face. When that crystal moves into an area of higher humidity, branches sprout from the six corners because of the way they project into the humid air. Sticking out farther causes branches to grow faster, in an example of a positive feedback loop.

Even slight changes in temperature and humidity tip the balance back and forth between the growth of branches and flat surfaces. In this way, a complex pattern emerges. Because each snowflake follows its own path through microclimates in the sky, each crystal is unique. Because the six sides of a single snowflake experience almost the same conditions, they grow mostly symmetrically. (A snow crystal can also be called a snowflake, but once crystals bump into each other and get messy, they can only be called snowflakes.)

Although the “childhood” of a snowflake’s growth typically only last 30-45 minutes, the result can be spectacular. From a single ice nucleator and water vapor in the air, we get the spontaneous formation of mesmerizing patterns. From chaos arises order. This is the quintessential example of something scientists call physical morphogenesis—the spontaneous creation of pattern and form by inanimate materials.

Of course, like kids of all species, some snowflakes generate chaos. A few end up as beautiful individuals, lauded for their perfection. Many more are scarred and broken. And a few fail to develop at all. Each is important for creating the snowpack we value. Each is ephemeral, spending only a short time in a particular form on this Earth.

Gazing out of my window, I imagined myself as a snowflake: tossed through the clouds, experiencing new environments, and growing up wild.

Watch this amazing video to learn more about Dr. Ken Libbrecht's research on snowflake growth, and to see him grow snow crystals in real-time by changing the temperature and humidity. 

More resources here!

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is now available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. The Museum is now open with our exciting Mysteries of the Night exhibit. Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

Subnivean Experiments

One evening in the 1970s, little Gary Siegwarth learned a lesson. While outside his family’s home in Iowa there had been a big snowstorm, inside there was ice cream—ice cream that had to be shared among five kids. Wanting to make sure that he got his fair share, young Gary took the cardboard carton out of the freezer, then out of the house, and hid it deep within one of the drifts. When he came back a day later, the sweet treat was just a melty, unappetizing blob.

An artist's impression of the event. ;-)

“I thought it was the perfect hiding place from my siblings,” Gary told me, “Turns out the ice cream cache quickly metamorphosized into a subnivean shake…I was surprised. I just never really thought about it.” Gary had accidentally discovered the magical realm of the Subnivean Zone.

I’ve been wanting to explore that world a little more, too, but instead of burying precious ice cream, I buried thermometers. The night before our first big snowstorm, I wrapped a few indoor/outdoor temperature sensors in plastic wrap and placed them where I thought snowdrifts would soon form.

One sensor is under the boughs of a hemlock tree. Deer and snowshoe hares are known to seek the cover of evergreens in winter, because those dense needles prevent some warmth from escaping to the stars.

Another sensor is out in the open—just to the side of the planned sledding run—and I made sure to snuggle it in under dry autumn leaves and fern stems. The third sensor is leaning against the base of an ash tree. This one I expect to become more interesting in the spring, when tree wells expand in the strengthening sun.

The final sensor is dangling about four feet above the ground, in the branches of a dying spruce, in an attempt to shade it from the sun and get the most accurate air temperature possible.

Thermometers in place, I snuggled in, too.

By dawn, the sky had shaken down about five inches of dry, fluffy snow. By the end of the day, the total was seven. I watched the digital weather station eagerly, as temperatures from each of the thermometers shifted and changed. I knew that the data would get more interesting as the air temperature dropped.

Sure enough, the evening after the storm, when air temps hit zero in the dying spruce, every other thermometer was significantly warmer, and none more drastically than the one placed in the open, under leaves, with the thickest blanket of snow. Its temperature read 30 degrees. Even as the air temp sank down to 8 below, the buried thermometer only reached 27.

Yes, I keep my house cool. The thermostat is set at 64 and this weather station sits near a window, so it's often even cooler. I wear a cozy sweatshirt, sometimes down vest, curl up under blankets, and often overheat if I'm doing chores! Among my friends I do not have the coldest house. Not even close. I've always been a fan of saving energy and saving money.

According to the International Dairy Food Association, the ideal temperature for ice cream storage is zero degrees Fahrenheit and should not rise above 10. It’s no wonder that young Gary’s ice cream melted! He had placed his stolen treat in the same microclimate as my temperature sensor in the Subnivean Zone.

As winter’s first snowflakes drift through the dark, some land on top of dead plants, fallen leaves, twigs, and other detritus of the forest floor. In many places, snow never fully reaches the ground. In addition, the residual heat of summer still radiates from the earth. This warmth causes the bottommost snowflakes to sublimate—or transition directly to water vapor without becoming liquid first. The damp air then rises through the snowpack and refreezes into a crystal ceiling above spacious (for a mouse) rooms and runs.

As the first flakes fall, they often don’t reach the ground. In the air spaces below leaves, sticks, and other objects on the forest floor, the Subnivean Zone begins to form. Photo by Emily Stone.

In this space, with a blanket of snow to trap the earth’s warmth, and a solid break against the windchill, temperatures hover around freezing. Deeper snow provides even more insulation, and all manner of critters—from mice to martens, bacteria, fungi, spiders, hibernating insects, frozen wood frogs, and more—rely on the moderated microclimate.

To Gary’s credit, it didn’t take much thinking for him to figure out what had gone wrong. As a kid in farm country, he’d heard many times that a blanket of snow was better for the alfalfa and protected it from winter kill. He also had plenty of direct experience with the relative warmth of snow forts.

And still, it can take a while for information to sink in. Years later, in junior high, teenage Gary was playing football at a neighbor’s house. They grabbed a snack of ice cream sandwiches out of the freezer and Gary buried his in the snow for safekeeping. As before, the deliciousness melted and oozed away. That was the last time he experimented with ice cream in the Subnivean Zone.

While Gary never admitted guilt to his family in the case of the disappearing ice cream (he thinks he probably got in trouble even while taking the 5th), he still learned something important from these two accidental experiments. And he went on to become a scientist.

I’m not going to put any ice cream at risk this winter, but I am going to watch eagerly as my experiment in the snow plays out. How will deeper drifts and colder air temps impact the Subnivean Zone? I’ll be sure to let you know when I find out!


Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is now available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. The Museum is now open with our exciting Mysteries of the Night exhibit. Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.