A botanist's field notes: excursions in all seasons

I bike to work this morning across the bridge over I-88 as I have done several times a week over the past 16 years. I am on the sidewalk facing traffic, the interstate stretching out over my left shoulder. It is the hour before sunrise. An endless line of headlights trundles toward me in fog.

I enter the Arboretum by the service gate. Fog sputters against the power lines overhead. Electricity for what seems to me the entirety of the western suburbs veers northward here at the tops of enormous towers, growling toward coffee makers, electric lights, and servers that stayed on all night processing our ceaseless questions (“What should I have learned about Napolean in high school?” “Can spinach give you kidney stones?”). I think, the hour is entirely mine, and I am sharing the thought with hundreds on this road alone.

Fog droplets scratch fine, parallel lines in the beam from my bike light, inscribed diagonal to my direction of travel. I lock up my bike and walk. The forest is backlit by the gray-white glow of the city. Trails generally seem longer in the dark than they do during the day, but I have never had that experience in these woods. A burl on a red oak is so like a hunched raccoon that I watch it uncertainly for a few seconds before I approach it, and then I touch it only after I am sure it’s not alive. Even then I’m nervous until my palm has registered “bark” instead of “fur” and my mind has been able to process it. The process is surprisingly slow.

I cross the bridge over the ditch frozen in its route to Lacey Creek. I take the corner around a divot in the moraine. The ravine down toward the wet prairie and the power lines opens up in front of me, and the car noise recedes. The sky is lit up in the northeast, a blend of the muted sunrise to come and light from the suburbs that surround us, plus the city further off. I walk through the planted spruces that rise like pilings beneath a skyscraper.

Just beyond the spruces, I hear the first natural sound of the walk: rain drops striking the dead leaves beneath the oaks. I put my hood up to watch the rain come in, but I realize after 30 seconds or so that I am not getting wet. I step off the trail, out beneath the bare canopy where I hear the raindrops falling, but I still feel nothing. I put my hands out and stand for a few seconds. Nothing. Yet all around me, I can hear the sound of water drops hitting the leaves. I spit to hear if it is the same sound, and yes, it sounds the same. For several minutes I walk with my palms outstretched and wait to feel rain. I stamp my foot to see if these are worms, which should withdraw into the ground at the vibration. Nope. I walk around, and the tapping stops as I approach and picks up as I depart, forming a roving mantle of stillness that extends away from me about 6 feet in all directions.

I reach Parking Lot 8 and walk east, parallel to I-88. The pattering in the leaves has let up. The noise of the interstate is as loud as it will be on this walk. The robins are as well. There are lights all along the highway. Likely they give the robins a signal to get going a bit earlier in the day. A red oak has broken off about one-third of the way up. It hit the ground when it fell and tipped backward. The crown and much of the trunk came to rest in the crotch of the still-standing trunk. A remaining branch is pasted from base to tip with marcescent leaves, and all is silhouetted against the glow of street lights.

The tapping on the leaves starts up again near the top of the hill. I sweep aside a handful of leaves, and springtails jump off. I sweep aside another, and there are more springtails plus a drowsy pill bug. The soil is cool, damp, and friable. I don’t see anything big enough to make the tapping sound that I continue to hear on the leaves, unless it is the springtails jumping in unison when I’m not looking. I disrupt a web and a spider dangles from my glove, a couple of millimeters long with a bright white abdomen. It flails in slow motion.

I return to my bike 45 minutes after I left it. The sky is bright enough now to counterbalance the noises of combustion engines and rubber on pavement. Will the world be that much quieter when the cars all go electric? I think of a night in the northwoods, out on my skis, when a meteor cracked overhead. That is the only sound I remember from that night. I think of many nights in the middle of Lake Monona in Madison in midwinter. Surely there was noise there from the surrounding roads, but if so, I cannot remember it. I wish for a quiet morning right here in this beautiful suburban forest.

“Listen,” W.S. Merwin writes. “With the night falling we are saying thank you / we are stopping on the bridges to bow from the railings / we are running out of the glass rooms / with our mouths full of food to look at the sky / and say thank you / we are standing by the water thanking it / standing by the windows looking out / in our directions… back from a series of hospitals back from a mugging / after funerals we are saying thank you / after the news of the dead / whether or not we knew them we are saying thank you… we go on saying thank you thank you.” And then species are going extinct in his poem and in our world, “forests falling faster than the minutes of our lives,” the world becoming a metropolis. And still we are saying, “thank you”.

I unlock my bike, and the interstate embraces the southeast corner of this 10,000 year-old patch of forest that I would like to have hiked 200 years ago, or 400 years ago, or even just a couple of decades before we all decided what the country really needed was an interstate system. All around me is the crackling of creatures in the leaves, jumping worms wreaking havoc, Collembola high-jumping over dried petioles of fallen red oak leaves, spring beauty shoots under the litter like a forest within the forest that keeps going and going. These things will outlast us all. Thank you, thank you.

I bike to work the wrong way down the road with my helmet dangling from my handlebars. I pass one of the security staff walking the road, and we greet each other. The robins are singing in the oak collection. As write these notes the next morning, I won’t be able to hear the interstate at all, just as I can’t hear the cars roaring past Lake Mendota in the middle of the night 35 years ago.

And though I do not know it as I unlock the door to work, the male red-winged blackbirds will gather in the marsh while I am sitting at my desk today, and a coyote will kill something in the prairie and stand eating it, watching the cars drive by. I’ll pass them both on my bike ride home tonight before I let myself back out through the gate.

9:45 a.m., 32F, overcast

To listen to and tell a rush of stories is a method… Its research object is contaminated diversity; its unit of analysis is the indeterminate encounter.
– Anna Lowenhaupt Tsing, The Mushroom at the End of the World

I enter by the hospital. Robins are chuckling. The snow has been alternately subliming, melting, refreezing. Squirrel and raccoon tracks have hardened into the crust. Rabbit pellets warmed by the sun have settled into craters. Fallen red oak leaves curled by the alternate forces of moisture and drought have carved silhouettes in the snow as they melt into it.

House sparrows are chirruping from the brush between the forest and the hospital parking lot. Buds on a gooseberry have started to expand. They form tight rolls a few millimeters long, bases sheathed in brown scales, their distal halves green, their young leaf-tips loose, making the edges look a bit frayed. This gooseberry is the first shrub I’ve seen breaking bud this year.

Tree bark contrasts starkly with the snow. Imbricated plates of bark on a black cherry, each curled at the margins, on a tree that died years ago and has rotted almost to nothing. Deep furrows on a black walnut, broken up into blocks. Smooth tracks running the length of a red oak. Hackberry cork split into deep ridges, layered like dolomite cliffs turned on edge. White oak bark salted with desiccated fruiting bodies of smooth patch fungus, cups extruded from the tree when the days were warmer and wetter, now clamped shut. Two trunks of a basswood arched over in parallel, striped, shoots sprouting from their backs and heading for the canopy, branch tips still hanging on to pale floral bracts and a few seeds.

A cottonwood less than a foot in diameter with corky furrows has crumpled about ten feet up, given up in a wind that bent it until it couldn’t go any further. Thousands of vessels and phloem fibers and sieve tubes snapped, leaving the inner bark to hang like crepe. Thousands more did not. So as the tree tipped downward, unbroken wood that folded as the tree went down layered against the wood that cracked, until the tip of the tree hit the ground and, 15 feet closer to the canopy, snapped backward, severing the crown from its base.

A red-bellied woodpecker is barking at the juncture between the forest and the marsh. It moves upward in short jumps, which seems a risky move to me, jumping with both feet and then landing. How does it not tumble backwards? The bird probes the trunk with its stiletto of a bill. It stops and drums against the tree, six or a dozen rapid strikes. It looks with its left eye, it looks with its right. Ed Yong writes that the left side of a bird’s brain, which controls the right eye, is specialized for focus and categorization. This bird, however, isn’t displaying any obvious eye preference.

After getting to about 20 feet up, the woodpecker drops to the base of a nearby black walnut and flies back up with a walnut in its beak. It lodges the nut in a crevice of a bent-over elm. The bird probes it, dipping in and out, seeming to find something in there. It flies off to another elm, where it pounds vigorously at the crotch of a branch and appears to find a few more insects. It pulls them out and scans its environment as it ingests one, then two more.

The woodpecker flies off. I watch it go, and my eyes come to rest at the broken top of a tree where two white-throated sparrows are hopping around.

I walk to the edge of frozen Lacey Creek. I follow other people’s footprints off the edge of the pier and out through the cattails to the open marsh. Joel Greenberg writes that before European settlement, most rivers in the Chicago Region were like this: broad, slow-flowing wetlands that might dry down in summer but rarely flashed into anything. Many today are ditches that swell within minutes to hours of a rainfall, sweeping soil and trash downstream in every storm.

The snow is creased parallel to the flow of the river. A crack not much wider than a crack in a plaster wall runs as far as I can see up- and downstream. I have left the people tracks behind. Two lines of cottonwoods grow towards each other at the south end of the marsh. There are cattails in all directions. The hillside ahead is a mound of bur oak savanna edged with a ruff of black walnut. I follow deer trails through the marsh and pass a squirrel excavation in the grasses at the boundary of the wetland. I walk upslope, take a minute to get the view from the bench on the hillside, and begin my walk toward home, clockwise around the open water.

There are more fallen red oak than I remember, hulks lying on top of the snow, their bases offset from the point where they broke off if they were long enough to scrape the ground when they struck, or right at the base of the tree where they fell if they are shorter. A hairy woodpecker calls. A rock dove flies over the forest toward the southwest. Someone is striking a metal pipe with a hammer behind the houses that line the back of the preserve. I watch for a minute but cannot figure out what this is about.

I follow the barking trill of a red-headed woodpecker for about ten minutes and find it climbing a dead ash tree. It noses its way into an excavation, moves to the broken top of the tree, and head-pumps and squawks noisily for a minute until it flies off to a red oak and is gone.

As I near the hospital, a gray squirrel crosses my path, running full speed on the ground and then detouring up along the side of a white oak as casually as I might run along the top of a curb. His head stays upright, his body sideways, cantilevered out over the forest floor. I imagine running down the hallway and, on a lark, taking to the wall for a few steps, because why not? You can see just a little better from up here, and besides: what fun is it to keep your feet on the ground all the time?

Morton Arboretum East Woods, 8:45 a.m., 15F, clear skies, ca. 2" of snow on the ground

Temperatures have dropped into the mid-teens, and the road through the Arboretum is streaked with thinly-sanded ice and snow from yesterday. It is cold enough that the ice is barely slippery if I bike attentively. Still, I think increasingly about how fragile this body is that I’ve been issued for a few decades. Through my 30s, I careened down hills as fast as I could, whether I was on my bike or roller skates. Then I hit a rock with my bicycle and broke a tooth. They never do grow back. This morning, I go slow and cautious to Big Rock visitor station, lights blinking at both ends, and tie up my bike.

A red-bellied woodpecker is barking as I walk onto the moraine. A medium-sized song bird has left footprints in the snow amid a scattering of hop hornbeam fruits. It lighted at one edge of the trail and headed initially straight across, then made a long jump about the length of its body and pivoted to scratch at the ground. I presume it was eating something here, likely the hop hornbeam seeds. It bee-lined to another spot about a third of the way across the trail, where it angled right. It made a counterclockwise loop, stopping midpoint to peck at the snow. It closed the loop, made another long, straight path, then another loop, picking at the smorgasbord all along the way. Then, it jumped and flapped, and the tips of the primary feathers on its left wing scraped sharp, concentric, 45-degree arcs in the snow as it flew away. I may have just missed it; these impressions appear to be fresher than the tracks of the squirrel that galloped downslope past me hours before I arrived.

Chips and leaves scraped up after the snow stopped falling are frozen hard. The sun rising over my right shoulder is lighting up the woods ahead of me, highlighting oak branches cleaved from the canopy in the late fall or winter and reclining on the forest floor. Broken branches lack the volition to elbow their old, dead leaves out of the way. Their young buds are frozen. Flowers pollinated last spring are desiccating. Their cambium will not begin to grow again this spring, packing on layers of phloem and, eventually, bark toward the outside of the trunk, building rings of water-carrying wood. But the thick residuum of its life is still locked up in a fallen branch. It will bleed sunlight back onto the forest floor for decades.

Dog tracks paralleling mine seem a bit large for a coyote, though I don’t know for sure. One other person has walked this trail since yesterday’s snow, out and back again, and perhaps this was their dog. I note this with my gloves on. Canada geese call from over Hidden Lake, and I write what I will later misread as, “Canada geese our hidden life.” Tracks of a raccoon plodding overnight or in the early morning run diagonally across the trail to a red oak, then cross back into the brushy woods in the opposite direction.

The snow is mostly blown away from the ridgetop of the moraine, forming grout between the paving of wood chips rather than a sheet over the top. I take a shortcut down the north slope toward Big Rock. The forest opens to prairie. Teasel stands ramrod straight. Indian grass is inclined and goldenrod knocked down by the season. Fallen stems form a network of raised veins beneath the snow, roofs over vole nests and pathways. A pileated woodpecker pounds loud and slow behind me, like someone chipping at a tree with a hatchet.

I follow coyote tracks through the field to a foxtail- and brome-dominated opening, grasses short enough for a few plantain to raise their inflorescences. Water pools and is frozen clear all the way down to the soil, encasing for a few days a cubic foot of old field. Two willow trunks curve up and away from each other in the shape of a letter ‘U’ and become brushy at their apex. A short Kentucky coffee tree grows with two bur oaks. All appear to have been planted at the same time in this opening. Perhaps one will still be standing in 250 years, but only one.

The coyote path follows the water through a ditch of wild rye and sunflower. The water flows back into the forest. It cradles the base of Big Rock as it turns to the north and courses through a culvert beneath the trail on its way to Hidden Lake, where Canada geese are still calling. To the northeast, chainsaws are running and smoke is rising from burn piles.

I walk back through the woods toward the parking lot following the coyote tracks. Wind is rattling the oak leaves. A downy woodpecker makes a long, descending, whinnying call. The sun is bright in my eyes as I continue down the south slope to my bike. White-breasted nuthatches are calling in all directions. Juncos are pipping in the open field.

I’ll leave work at 4:30 this afternoon, before the sun sets, so that I can see the icy patches on my way out. Juncos will fly off from the roadsides in both directions as I go.

Trail north of Big Rock visitor station, 8 a.m., 35F, cloudy

Clouds are banked up in the southeast and interleaved with sunlight as I bike in this morning. The woods are breezy when I arrive at Big Rock Visitor Station and lock up my bike.

Annual bedstraw has grown no larger in the week since I noticed it poking through the fallen leaves. About 20 plants are scattered sparsely over an approximately-half square meter. Further down the trail, fallen oak leaves are scraped up along the trail, exposing spring beauty shoots and seedlings. I pinch the soil around the base of the tiniest of them to pull it out, lay it in my hand and flick the dirt off it. The stem is a little larger than a tubifex worm, overhanging the edges of my fingertip by a few millimeters. The cotyledons—the seed leaves, the ones that have been curled inside the seed—are about half as long as the stem and only slightly greener than it. They resemble white cotton dipped into a dye bath, allowing the color to migrate up onto the apex of the stem, which fades to white. The shoot is bent at the intersection between cotyledon and stem like the bend of a wire hairpin, the kind that comes 100 to a pack, curved to incline sharply backward. At the base of the stem, a bundle of root hairs holding soil in place, then a few straggly roots. This plant is throwing it all into the shoot right now, racing to get above the leaf litter in time for spring. (By contrast, the annual bedstraw seedlings germinated in the fall, and each sports a ponytail of roots to get it through the winter.) I lay the spring beauty seedling on the knee of my corduroys to get a photo. The stem is narrower than the wale across which it lies.

A white-breasted nuthatch is calling, but nothing else that I notice. Scrapes of open soil have opened perpendicular to the trail from rain washing downslope last week. The ditch is flowing today, ice-free, riffles below the larger stones visible from where I stand about 30 feet up. A sugar maple stump a few inches in diameter, sawed off about a foot and a half above the base, lies on its side along the trail where it’s been chucked. I tip it up: the severed roots are blackened by soil and moisture and netted over in white mycelia.

The trail turns north. Through the trees to the east I can see the open floodplain beneath the high-tension lines. There is a section of unplowed prairie there that was destroyed in part when ComEd put the power lines in decades ago. I know one of the volunteers who works down there, and she is a singular individual, driven and knowledgeable. Prairies like this are saved and worked back to health by people who spend hundreds of hours educating themselves on how to do this work, then thousands of hours doing it. My eyes shift back to the woods below me. The entire slope is a mid-winter mess of bedraggled pokeweed, bleached stems falling all over themselves and each other down to the edge of the floodplain. Robins are chirruping in the bottomland, where there moist soil holds invertebrates in abundance. A single call note: probably a junco.

Upslope, a 60-foot white oak collapsed at its base as it fell over. The broken ends of the fallen tree and the base of the stump are riddled with insect burrows, I believe from ants. The stump is split in half, the upslope side still 10 feet tall and clothed almost entirely in a reticulum of black honey mushroom (Armillaria) rhizomorphs. The tree must have snapped at the weakened base as the trunk began to fall. The trunk sheared upward to where it is broken off now. The falling trunk cantilevered for a fraction of a second and then fell straight down onto the ground, so the slivered end of the trunk came to rest about almost as far on the other side of the trunk as the standing edge of sapwood remaining. This is what I infer. Much, much less likely: the tree fell over and then was hoisted up by a giant, shifted back toward its base about 10 feet, and set back down; the giant worked carefully and disappeared without leaving a trace. The length of tree is bird-and-insect chewed, weathered. A tiny artist’s bracket is growing on one side. The tree rotted in place, serving the forest for years after it died. It’s been down on the ground at least long enough for a squirrel to leave an empty acorn shell.

A fallen tree further along the trail is striped with bright green moss and snow that has fallen, melted, frozen again to form icy aggregates. It is dusted with white chips from a sugar maple that was sawed up next to it. Beggar’s ticks are spindly and grabby in the understory, stealthy and lackadaisical but efficient enough: I think I’ve eluded them altogether on this walk, but later in the day I’ll pick about 50 burs off my shoes.

The trunk of a tree that fell decades ago is gone. It must have been sawed up and removed; I can’t imagine that it decomposed in anything less than 30 or 40 years. What is left now is a tip-up and pit beside it, about two-and-a-half feet between the soil surface and the base of the pit where pokeweed grows and enchanter’s nightshade branches and oak leaves spill in. The edge of the pit is rimmed with slabs of bark and sapwood that mark the stump’s perimeter. These remnants of the hulk that stood here for more than a century are growing turkeytail rosettes in abundance.

On the walk out, I run into a group of six volunteers hiking in to burn brush piles. We talk for a minute about an instrumented forest plot nearby, marked with several blue leaf-litter baskets and a weather station that looks like a Mars lander. In the parking lot, I talk with two of the field crew about what I’ve been seeing, and they tell me about the work they’ve been doing in there: removing sugar maples, removing some of the ironwood, leaving the oaks and hickories and daylighting the woods for the ephemerals. How much more spring beauty will we see this year and next because of their work?

7:45 a.m., part clouds, a little wind, 45F

On my bike ride into work this morning, a field crew is burning brush piles in the woods. Flames rise several feet beyond the tops of the human-high piles of branches ranging from as narrow as my pinky to as thick as my forearm. One of my colleagues fans a recalcitrant fire with a leaf blower. Another transfers brush from a truck onto the fire. We greet each other, and they graciously hold up their work for a few moments as I squeeze past them.

I tie up at Big Rock visitor station and walk the trails to the north. Spring beauty shoots continue to emerge in the cool, damp dark beneath fallen leaves. Today the etiolated stems I find are as slender as a tangle of embroidery floss, so fine that I wonder if they are seedlings. I dig them out and find a dark, toothlike corm the size of a spit tangerine pip. This is the plant’s persistence from one year to the next. About a dozen short roots come off the corm. I later read that this species is nonmycorrhizal, leading me to wonder whether I have broken off long-haired roots as I dug this out of the ground. The short leaves at the shoot tips are bent sharply backward like a dancer stretching before a performance. Further on, I’ll find one with flower buds bundled into a knot the size of an ant’s head. A white-breasted nuthatch is calling.

Cotyledons and first leaves of what I take to be annual bedstraw are pushing up through windows in the litter. I have never noticed the cotyledons before, or forgotten them if I have. They are ovate in outline and nearly as large as my pinky nail, a surprise for a plant that will have long-slender leaves at maturity. Right now, they are short, fat, sharply apiculate and toothed along the margins, their upper surfaces scabrous with tough little hairs. This plant germinated in the fall or winter and has been growing for awhile. I dig one up and lay it in my hand to photograph. The roots trail across my palm, almost as long as the stem angling across my fingers. There is no corm or bulb to get these plants through the winter. They live on wits, good fortune, and the law of big numbers: every plant is at enormous risk of seeing its lineage snuffed out this season, but the species as a whole will be here long after we are gone.

Leaves are mussed up by squirrels tussling and digging up acorns. The ditch below is still, standing water skimmed with ice that covers only about a third of its surface. Some plant I don’t recognize that smacks of a Eurasian ground-cover grows rigid, tall, evergreen along the edge of the trail. I photograph it and upload it to iNaturalist, and the machine learning engine suggests woodland phlox. I accept the identification, then find that I photographed the same species in the same location almost seven years ago. There is some chance it’s the same plant.

A dead tree stands six inches in diameter and snapped off a few feet above my head. A woodpecker excavated a few holes near its base sometime in the past month or two, strewing white wood chips. The holes are too small for a pileated woodpecker. They seem a bit large for a downy or even a hairy woodpecker. I put my money on red-bellied woodpecker. All are common enough in these woods. Whoever it was dug deep. Did it find a warren of beetle larvae?

A small colony of bleached American pokeweed is still standing after the snows and winds of winter, stems dark-streaked perhaps by fungi, leaning against one another, one overtopping me. Beyond them a red oak has tipped over, huge, about 150 feet tall and as big around as any in the East Woods. Some of its larger branches fractured on impact, but the canopy lies in only a few pieces, still clothed in the past year’s leaves. The roots have pulled up clay and rock. Thick shards of bark are embedded in the ground, sloughed off hastily as the tree blew over.

Later in the day, while I am working through oak specimens in the herbarium, rain comes down in torrents, beating against the side of the building. I bike out in the early dark. It is warm and raining, but more slowly, rattling against my hood as I pass the brush piles that have burned down but still glow orange in the falling rain. I bike to the exit gate. Outside that gate, anything could happen. I unlock it and bike home to Rachel and the boys.

I am writing this the next morning, recalling my ride from notes and photographs. It rained all night, and I study the puddles in our backyard as my tea steeps. I lose a half-hour of writing to reading the news, about the U.S. invading Venezuela, about ICE agents shooting and killing a woman in Minneapolis, about health care. I think of these lines I learned earlier this week, from Bertholt Brecht:

What times are these, in which
A conversation about trees is almost a crime
For in doing so we maintain our silence about so much wrongdoing!

Are the brush piles still smoldering, rain hissing against the glowing logs?