Thursday, October 27, 2022

What the North Wind Swirls

It’s hard to know where to look at this stage of fall. Bursts of color still shine from tamarack swamps and groves of oaks. Bedrock outcrops, old foundations, and other bits of history are peeking through the bare trunks of “see-through” season. And dry leaves dance ahead of the breeze, tickling our eyes for attention.

Among those leaves are little dancers who don’t need wind to help them fly. Flocks of dark-eyed juncos and snow buntings have arrived from the far north. They will help animate our landscape now that the warblers, vireos, hawks and other friends have left.

Some folks call juncos “snowbirds,” because their plumage imitates the winter color scheme of dark skies above and white snow below. Here, in their overwintering habitat of the lower 48, they also seem to bring the snow with them as they move south each fall.

“Like the chiming of myriad crystal bells, a flock of juncos was gossiping among the branches. Their notes were so fragile and unbelievably pure they seemed to float on the air.” – Lois Nestel. Photo by Emily Stone.

Dark-eyed juncos breed across Canada. The northern forests of Wisconsin and Minnesota are at the southern edge of their mid-continent breeding habitat, and we sometimes see a few juncos through the summer. You can identify them by the flash of white on their outer tail feathers as they fly away. The real influx comes when the leaves begin to fall, as juncos head south to their winter range.

Under the feeders, along roadsides, and in open areas, juncos will forage by hopping, scratching, and pecking at the leaf litter, and flying up to glean food from low twigs and grasses. By eating ragweed, crabgrass, and pigweed seeds in the winter, and insects in the summer, juncos help keep pests under control.

And they make eating weeds look fun. These sparrow-sized birds sometimes land on the top of a grass stem and use their 25-gram bodyweight (the equivalent of 25 paperclips) to “ride” it to the ground. From there, they can stand on the seed head and feed more easily.

Dominance hierarchies in winter flocks mean that females get chased off food when there are too many males around. As a result, females tend to migrate farther south. There’s another reason for the difference in their preferred winter latitudes. Males will risk harsher weather in order to get a jump start on spring migration and arrive first at prime breeding territories. When the females arrive a little later, they get to select a nest site within the territory of the male they choose.

While juncos get the nickname “snowbirds,” snow buntings take that idea to the extreme. There is no apparent northern limit to their breeding range, and they have the ability to spend the winter farther north than almost any other bird.

While snowshoe hares turn white for the winter, snow buntings add brown and spend the season with rusty patches on their feathers. It helps them blend in on the bare fields and among the grass stems where they feed in the United States (eating more ragweed seeds, thank you!). By April, that color has worn off to reveal pure white plumage that will match their still-snowy Arctic breeding habitat.

This female snow bunting blends in well with the mix of snow, bare ground, and dry grasses on her wintering habitat. Photo by Charles J Homler via Wikimedia Commons.

Just like juncos, the winter habits of male snow buntings are dictated by their need to return early to claim a breeding territory. Since snow buntings nest in deep cracks and cavities in rocks to avoid predators, their nesting sites are limited. Not going too far south and arriving early back north to claim one is essential.

Nests in those cold rocks must be lined with fur and feathers, and the eggs incubated almost constantly. Males are attentive, and bring food to their mate every 15 minutes.

While it may seem excessive for snow buntings to endure such cold, their breeding is carefully timed so that chicks are hungriest right when insects are most plentiful. Hard winters seem to keep this timing well-matched. Counterintuitively, warm springs that shift breeding earlier produce a mismatch with their food source. Studies show that nestling weight declines.

“Those lovely little wraiths, the snow buntings,” wrote Lois Nestel, the Museum’s founding director and naturalist, as she detailed the beauty of winter in the Northwoods. Of juncos, she wrote: “… I was greeted with one of the woodland’s loveliest sounds. Like the chiming of myriad crystal bells, a flock of juncos was gossiping among the branches. Their notes were so fragile and unbelievably pure they seemed to float on the air.”

As the swirling dance of these two snowbirds livens up the roadsides of fall, I’m grateful that they make the Northwoods their winter home.

Author’s Note: Portions of this article are reprinted from 2015.

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is now available to purchase at 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 Growing Up WILD exhibit. Follow us on Facebook, Instagram, YouTube, and to see what we are up to.

Thursday, October 20, 2022

Shades of Rot and Life

In the dim light, under the thick, hardwood canopy of the forest in Fox River Park, Waukesha, death was everywhere.

Autumn leaves carpeted the ground in shades of brown and yellow, with occasional splashes of blood red. Snags stood among the living trees, their decorticated (a fancy term for bark-less) trunks smooth and dry. And long stripes of rusty brown crumbles marked where fallen logs were melting into the ground.

Of course, life was everywhere, too.

Beside the wide, dirt trail, a ruffle of turkey tail fungus cascaded down the graceful curve of a tree trunk like an earth-toned ball gown: a damsel of decay. While the volume of fungal frills—each with a velvety top, concentric bands of color, and tiny pores in the white undersurface—was impressive, the bulk of the being was hidden inside. Intertwined among the wood cells, hidden from view, the fine, white threads of hyphae (the actual body of a fungus) were hard at work. The tree itself was dead, and yet still full of life.

Turkey tails are a white-rot fungus, which means that they have the ability to decompose the major components of a tree. That’s not easy. Wood is tough because the cellulose and lignin molecules it’s made of are long chains of elements that are difficult to break apart. Lignin in particular gives wood its strength.

Do you remember learning about enzymes in your high school science class? I chewed on a saltine cracker until it became sweet. Enzymes in my mouth broke down the long chains of starches until they became glucose, a simple sugar. In a similar, but external process, fungi exude a series of enzymes into the wood, and those enzymes split the chemical bonds of cellulose and lignin, resulting in shorter chains of glucose. The sugar dissolves in water, and fungal hyphae absorb it directly through their cell walls. Carbon dioxide is released to the air.

Because turkey tail and other white-rot fungi break down cellulose and lignin simultaneously but leave some of the cellulose for last, the wood they work on becomes soft, white, and stringy. A large portion of the nutrients once trapped in the wood become available to cycle through the ecosystem again. Bacteria jump in to use those nutrients, paper wasps turn the soft wood into nests, and moose can even eat wood softened by artist's conk fungi.

The next day, I headed back along that same trail with a group of Master Naturalists doing an activity called a Professor Hike. I picked a student with a sense of humor, stationed her by a stump, and made her a duct tape name tag that read: Professor Brown Cubical Butt Rot. “This isn’t a disease caused by too much time in an office chair,” I joked. The name is real, and quite descriptive.

As the Professor explained to her classmates, this tree stump was being decomposed by a brown-rot fungus. Unlike the turkey tail, some fungi can only decompose the cellulose in wood cells, and the lignin left behind is brown. The fungus typically affects the bottom of a tree trunk, which in forester and logger lingo is the “butt.” But the cubical part of the name is most interesting.

Brown-rot fungi send hydrogen peroxide rapidly diffusing through the wood of a tree. The chemical modifies lignin just enough to get at the cellulose also in the cell walls and snips apart the long chains of cellulose into carbohydrates. Two days later, once the destructive peroxides have dissipated, enzymes finish the job of turning the carbohydrates into sugar. The fungus absorbs it.

The process works more quickly than the totally enzyme-dependent decomposition by white-rot fungi, but leaves all the lignin on the table. The lignin-rich wood turns brown, shrinks, and cracks into roughly cubical pieces. Hence the name, brown cubical butt rot. The “professor” bragged about her name all day—accidentally teaching about decomposition along the way.

We’re often tempted to turn everything into a competition. Are white-rot fungi superior because they can break down lignin? Or are brown-rot fungi better because they can work more quickly? In fact, the first to arrive often has the advantage. And when the two types of fungi compete directly on the same log, brown-rot fungi win the short game by being able to access the energy in cellulose quickly, while white-rot fungi play the long game as they slowly access more of the energy stored in the wood.

In the end, the ecosystem wins. The rusty colored crumbles of brown-rot fungi contribute to healthy soils with more capacity to hold moisture and nutrients. White-rot fungi, and especially competition between several different types of fungi, results in a tree being more thoroughly recycled and the materials becoming available for new growth. Humans are also treated to delicious meals when the fungi fruit. My favorite—chicken of the woods—is a brown-rot fungus. Shiitake and oyster mushrooms; plus the medical turkey tails, are all white-rotters.

Lignin and cellulose; brown and white; death and life. In the end, they aren’t all that different.

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is now available to purchase at 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 Growing Up WILD exhibit. Follow us on Facebook, Instagram, YouTube, and to see what we are up to.

Thursday, October 13, 2022

Stories Buzzing in a Wasp Nest

A colorful crew of Master Naturalists in my “Finding the Stories in Nature” workshop trickled out of the picnic shelter at Fox River Park near Waukesha, WI, and regathered next to a spruce tree on the lawn. “Here’s your first challenge,” I told them. “What stories do you see?”

A few students came closer and poked at the papery gray remains of a bald-faced hornet nest in the tree. They observed the torn bottom of the once-oval shell, and the way the spruce needles poked up through the paper where the nest encompassed the twig. Someone pointed a tentative toe at the circle of dead brown grass directly below the nest, and reached out as if to touch the paper disc of honeycomb that had come to rest on a lower branch.

“Well,” one student began tentatively, “someone sprayed it.”

I nodded encouragingly, watching their gears turn, and then jumped in to share the ideas that had been churning in my own head.

“I see a story of fear,” I began.

Someone noticed the nest—too close to the picnic shelter—or maybe a visitor complained about a wasp attracted to their sugary drink. (Bald-faced hornets are technically wasps, not true hornets.) Worried about severe allergies, or even just some painful stings, someone decided that the risk was too great, and the nest couldn’t stay.

A park maintenance person took a can of insecticide off the shelf, and drove over in their truck to take care of the problem. It looks like they sprayed, and then tore open the bottom of the nest, and then sprayed some more. The surrounding spruce needles turned brown. The grass turned brown. And all that remains of the dozens of bald-faced hornets in the colony are two mummified bodies caught in the act of crawling toward the exit.

“I also see a story of life,” I continued.

Last fall, at about this time, a new queen emerged from her colony, found a drone from another colony, and mated. The male drone died, while the new queen burrowed into the soft wood of a rotten log and hunkered down for the winter. Glycerol in her cells kept the sharp crystals of ice at bay.

Last spring, the queen emerged and began to build her colony. With strong jaws, she scraped up soft fibers of rotting wood, mixed them with her own saliva, and formed them into a small disk of honeycomb-shaped cells and an outer shell of paper. (This outer shell makes it easy to tell her nest from that of a paper wasp. Their nests leave the hexagonal cells exposed.)

Our bald-faced hornet queen laid her first set of eggs (fertilized with the help of that short-lived drone last fall), then fed her larvae chewed up caterpillars until they were ready to pupate. Twenty-five days after the eggs were laid, the queen finally had subjects to command. She retired to the nest to continue laying eggs while her daughters ventured out to hunt caterpillars and gather paper-making supplies. As the colony grew, they enlarged the nest by transferring material from the inside to the outside.

“I also see a story about risk and reward,” I add. Autumn is when wasps become gamblers. If the queen is too quick in laying the unfertilized eggs that will become male drones, and initiates the formation of new queens too soon, the colony may not reproduce to its fullest capacity. Maybe the colony could have gotten just a little bigger and made just a few more new queens to carry on their genes…

On the other hand, if the queen waits too long, hard frost may kill the whole colony before the new queens can mate and burrow safely into a hibernaculum. The new queens are their hope for the future—the old queen, the drones, and the rest of the colony are doomed to frost no matter what.

Killed by chemicals instead of frost, these bald-faced hornets are frozen in the entry way to their nest. Photo by Emily Stone 

“What other stories do you see?” I posed again to the group, and we returned to talking about fear. One after another, members of the group shared their personal stories of being stung, being chased, and being scared.

Aggression is part of the insect’s story. At any given time, bald-faced hornets have dozens of tender, energy-rich eggs, larvae, and pupae squirreled away in their nest. The colony also contains a significant number of workers whose job goes beyond providing food and shelter to protecting the nest from hungry bears, foraging skunks, and scared humans. More than 99% of wasp species are solitary, with a single female laying eggs and provisioning the larvae all by herself. Those species are rarely aggressive.

Finally, an artist in the group peered closer and admired the shades of gray layered in subtle stripes and swirls. Red-eyed vireos like this material, too, and often incorporate scraps of wasp paper into their own nests, a type of tricky camouflage meant to deter potential nest predators.

From death, to life, to other lives, this nest had tales to tell. “Good work,” I told the Master Naturalists as I motioned toward the woods. “Now let’s go find some more stories!”

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is now available to purchase at 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 Growing Up WILD exhibit. Follow us on Facebook, Instagram, YouTube, and to see what we are up to.

Thursday, October 6, 2022

Firefly Fall

Signs of fall were abundant during my recent trip to the Boundary Waters. As I wrote last week, my cousin and I saw flickers, warblers, loons, and geese on migration; and swans eating wild rice. Another sign of the season was that we had a campfire every night.

Maybe some of you would have nightly campfires during a muggy July trip when the mosquitoes swarm at dusk, it hardly cools off at all, and the Sun barely dips below the horizon long enough to get some sleep. That’s not me, though. And even when the Sun sets earlier and the bugs die down, sometimes I’d prefer to spend a rare, bug-free, warm evening with the far-off fire of the stars.

On this trip, evenings were long enough—and chilly enough—that we had time for both fire gazing and star gazing, and perfectly gooey s’mores every night.

I’d just settled into a comfy spot on a log near the fire, zipped up my down vest, and was staring thoughtfully into the shadows when a light outside the fire grate, below the stars, and not near the water caught my eye. It was pale, and dim, and seemed to be coming from the network of white pine roots that lay exposed in the thin soil across this rocky point. Suddenly, the fire wasn’t the most exciting light in camp!

I memorized the location of the glow, then dug through my dry bag for my macro camera, and fished a headlamp out of my vest pocket. The glow pulsed again helpfully, and when I swept the flashlight across the roots, it illuminated a one-inch-long armored vehicle crawling on weathered wood.

The long, oval body was covered by a dozen dark segments of exoskeleton that allowed for limited flexibility when crawling over the curved root, bridging between root and ground, and navigating clusters of pine needles. When I rolled the critter over, the belly segments were pale, and the six tell-tale legs of an insect poked out from the front half. No wings, though. Turning off my light, I waited until the soft glow kindled and faded one more time.

The larvae of all fireflies are bioluminescent, and I was eager to see if the iNaturalist database would confirm my hunch. Sure enough, Photuris genus was the only ID suggestion that popped up. A firefly larva!

Most of us are lucky enough to be familiar with the twinkling summer lights of adult fireflies—a type of beetle. In a firefly’s light organ, oxygen reacts with luciferin to produce light. Males blink a species-specific pattern to attract females. If they’re lucky, she responds by flashing back, allowing him to find her hiding spot in the grass. He flies down, and they mate.

Many species of fireflies only live for a few weeks as an adult, and are so focused on mating that they don’t even bother to eat. Female Photuris fireflies are not so selfless. They have learned to flash the patterns of other firefly species, tricking the unrelated males into thinking they’re going to get lucky. Instead, they get eaten. This habit has earned Photuris fireflies the nickname “femme fatales.”

Their victims contain toxins in an effort to dissuade predators. In a clever move, female Photuris simply incorporate those toxins into their own bodies, making themselves taste bad to their arch enemies the jumping spiders.

The children of lightning bugs aren’t any less ferocious. In fact, fireflies who aren’t femme fatales must do ALL their eating in the larval stage—just like the caterpillars of some moth species, but protein instead of plants. Slugs, worms, and other insects are all on the menu. 

And then, they must find a safe place to escape the clutches of Old Man Winter.

Rotting logs, fallen leaves, and damp soil all provide protection from the most bitter cold, enabling firefly larvae to survive the season. Sometimes they must endure more than one winter before growing big enough to pupate in the spring and emerge as an adult. Mild winters are a boon to the population, as fireflies may persist in greater numbers and emerge earlier in spring, giving them more time to grow and reproduce.

You can help fireflies survive by creating wild corners of your yard filled with rotting wood and leaves. They will be winter habitat for many beneficial native insects and critters. Being judicious with your outdoor lighting is considerate of many nocturnal neighbors. Using native plants in your landscaping, and NOT using herbicides or pesticides will all increase habitat.

As nights sparkle with frost instead of fireflies, it’s a good time to make sure our yards provide just as good habitat as wilderness campsites for these fanciful and ferocious critters.

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is now available to purchase at 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 Growing Up WILD exhibit. Follow us on Facebook, Instagram, YouTube, and to see what we are up to.