“The extra minute [per day] had nothing more to show than what was already present – it showed just a minute more of that. More light but, so, all begins again. Today, there was nothing else to see but there was one more minute to see it in.”
—Dee, Tim. 2020. Greenery: Journeys in Springtime, p. 15. Jonathan Cape, London.
Spring beauty—Claytonia virginica—is one of our most common spring ephemerals. It emerges, flowers, fruits, then dies back by the time the canopy closes. You’ll find its strappy leaves flopping onto the leaf litter in mid to late March. But I begin looking for the first plants of each year in December. Scrape aside the sodden oak and maple leaves in the weeks before the winter solstice, and you may find a scattering of Claytonia crawling over the surface of the soil. The Claytonia are not alone. False mermaid seeds that fell in March are said to put out roots by early winter, though I have never found them at this very early stage. The staminate spikes of Carex woodii and probably most other woodland sedges, if not all, are preformed, white and naked, buried among the leaf bases. December houses the shortest day of winter as well as the beginning of the forest year.
Not all spring beauty shoots start growing in midwinter, or at least not all of them grow enough to be visible above the soil’s surface, but I generally find spring beauty somewhere in the woods by the time the solstice rolls around. I was thus a little surprised that Brooklyn and I failed to find any spring beauty on the second Saturday of December this year, on a morning walk through Maple Grove. Instead, I found an individual of false rue anemone with leaves as big as my fingernail, breaching the oak leaves spilled out beneath the trees. False rue anemone is another spring wildflower that often starts growing in the fall. Its seeds lack a strong physiological dormancy. They germinate in autumn as a consequence. Adult plants similarly send up new leaves in winter or fall, or at least some of them do. A few individuals may flower in the fall in parts of the species’ range.[1] I have seen very small false rue anemone in midwinter. I’d never seen any this early in the month, however, nor any with leaves so large at any time in winter.
Eastern white oak acorns were scattered along the edge of the gravel trail. They had put out roots two or three months earlier, almost immediately upon dropping, which is typical of eastern white oak and many of its closest relatives. Taproots grow several inches into the soil within a few days after the root tips emerge; the shoots generally do not grow until the next year. Only one acorn of about fifty that I counted on this walk had successfully embedded its root in the gravelly soil. Acorns have a tough time even in the best of soils. Fewer than one percent of eastern white oak acorns may make it all the way to the seedling stage, even if they are protected from seed predators.[2] At intervals along the trail, Brooklyn and I passed acorns that had shed their shells, allowing the fleshy cotyledons to relax and spread away from the epicotyl, that portion of the shoot that emerges above the cotyledons. The cotyledonary petioles were extended, pushing the seed leaves away from the growing plant. Like the false rue anemone, white oak is getting a jump on spring.
Sunday morning the next week, Brooklyn was unusually interested in the smells beneath one of the honey locusts planted along the Downers Grove railway platform. It took me a moment to realize that she was nuzzling the severed head of a duck. It was badly weathered, feathers rumpled and matted by the rain. The spine was still attached, well past the point where it would have attached to the body in a live duck, and shrouded in grey tissue. We get little whiffs of wildness like this even in downtown Downers Grove, a place of which the Du Page Title Company boasted in 1948 that “There is a peacefulness, a sense of subdued and quiet living that makes the visitor from the city feel as though every day were Sunday. Only the occasional bark of a dog and the constant clamor of the birds break the silence.”[3] The clamor as a fox caught this duck by surprise is likely not what the Du Page Title Company copywriters had in mind.
Red-bellied woodpeckers and white breasted nuthatches were calling when we reached the Denburn Woods entrance to Maple Grove. The pond there was skimmed with duckweed. From a distance, the pond’s surface appeared as green as it might have in July or August. Some duckweed fronds were turning white, but I only noticed the variation in color when we approached the shore. The vast majority of these rice-grain-sized plants will live through the winter, submerged beneath the ice (if it should ever form this year).[4] Brooklyn and I headed up the hill to the south, then got antsy and crossed westward through the woods. We meandered between the trails that flank the east and west margins of the preserve, looking again for spring beauty. Slugs were still and cold underneath the thick mats of maple leaves that will persist until the worms get busy next year. Tiny millipedes coiled at the light. Red oak acorns lay inert, many with their sides chewed in. The growing tips of a few white oak acorns were gnawed away. We came across a little pile of deer scat, 10 or 15 turds. A squirrel scolded us from high in a sugar maple.
We passed the long-furrowed trunk of a fallen tree speckled with lichens and mosses and the bleached stumps of decimated chicken of the woods. Flecks of fungus spattered the bark of a white oak down to an apron of bright green tree-skirt moss, like a dusting of unnaturally large snow flakes. Burned-out sacs of stump puffballs huddled on the tree’s root flare. A dead American elm, still standing, was inscribed with bark beetle trails on both the exposed wood and the inner surfaces of the bark sloughing off. The trails radiated outward from a gallery carved in the tree, each trail the work of a hatched larva feeding its way toward adulthood. Springtails jumped at the base of a sugar maple. A colony of mayapples was nosing its way aboveground, a handful of shoots protruding by a few millimeters through the soil’s surface. Yellow jelly fungi dotted a fallen tree.
On the west edge of the preserve, we came across several inch-tall shoots of broad-leaved wild leek. Some of the shoots were nearly two inches tall, hidden beneath the fallen leaves. Around them stood a scattering of dried scapes of last year’s flowers. The pedicels were still tipped with floral scraps. The broad-leaved wild leeks on the east side of the preserve were also putting up shoots. No spring beauty that I noticed.
Two days after Christmas, we visited friends in Madison, Wisconsin. We woke to a full moon framed by the window and the trees in the park nearby. We wandered downstairs one by one, had coffee and ate cookies from the night before, shared photographs. Our friends pointed out a yellowwood in the back yard, and as we talked about whether the tree might have encountered bedrock as it grew downward through the soil, our friend noticed that the bulbs planted at the base of the tree were already sprouting.
The forest year begins this way, with a few acorn epicotyls, a false rue anemone with unusually large leaves, preformed shoots of wild leek and mayapple. Plant populations vary in essentially every characteristic that matters: how tall you grow, when you emerge, leaf out, flower, fruit, and die back. This has been an unusually warm early winter at the end of an unusually warm fall. But I can’t say whether the timing of these accidental December finds are out of line with a typical year. “Variation,” wrote Theodosius Dobzhansky, “is the fountainhead of evolution.”[5] Variation is also a gamble. Some early sprouters get just the head start that they need, survive through the winter as shoots beneath a bed of leaves, sopping up warmth from the soil and shielded from the worst of winter by the blanketing snow and leaves. They hit the ground running when spring comes, and they have a little extra time to flower, fruit, and provision their fruits for the coming year. They get more offspring into the next generation. Other plants emerge in December only to be knocked back by a hard frost. The population evolves in either case.
My field notebooks are dominated by dates when leaves emerge or begin to turn colors in the fall, when flowers open in spring through summer, when fruits ripen, when shoots appear in the forest or prairie after a burn. The dates of wildlower bloom are known from hundreds of species in the forests that Henry Thoreau botanized around Concord, Massachussetts and the fields where Aldo Leopold and his family built their shack and where Leopold wrote A Sand County Almanac.[6] In the herbarium where I work, we can track changes in bloom date for trees in our living collections over the course of nearly 100 years. But I know comparatively little about about what goes on beneath the litter and the snow in midwinter.
Last friday, the narrow-leaved wild leeks at the south edge of Lyman Woods, up along the ridge, were not putting up shoots at all that I could see. Each flower was broken off at its base, leaving a starburst of needle-like pedicels at the tip of each dried scape. Is the difference between these leeks and the sprouting broad-leaved wild leeks in Maple Grove a difference between species, between populations, or between sites? Or all three Understanding the difference between these kinds of variation is key to understanding how plants will evolve in our changing world.
The morning of New Year’s Eve, Rachel and I walked through the Arboretum with friends, after a light snow, talking about the past year, the coming year, the Aleurodiscus on the ironwoods. Somewhere along our route, there were probably spring beauty shoots growing in anticipation of spring. We didn’t see them. However, two pileated woodpeckers led us out of our walk and into the new year. I am always hopeful that I’ll find young pileated woodpeckers at the Arboretum. Perhaps 2024 is the year.
Plants referenced
- Allium burdickii — narrow-leaved wild leek
- A. tricoccum — broad-leaved wild leek
- Claytonia virginiana — spring beauty
- Enemion biternatum (= Isopyrum biternatum) — false rue anemone
- Lemna sp. — duckweed
- Ostrya virginiana — ironwood
- Pseudanomodon attenuatus (= Anomodon attenuatus) — tree skirt moss
- Quercus alba — eastern white oak, or white oak for short
- Ulmus americana — American elm
Baskin JM, Baskin CC. 1986. Germination Ecophysiology of the Mesic Deciduous Forest Herb Isopyrum biternatum. Botanical Gazette 147: 152–155. ↩︎
Stringer JW, Taylor L. 1999. Effects of leaf litter depth on acorn germination. In: Stringer JW, Loftis DL, eds. Proceedings, 12th central hardwood forest conference. Gen. Tech. Rep. SRS-24. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station, 289–290. ↩︎
Federal Writers Project, ed. Marion Knoblauch. 1948. DuPage County: A Descriptive and Historical Guide, 31. ↩︎
Jewell MD, Bell G. 2023. Overwintering and re-emergence in Lemna minor. Aquatic Botany 186: 103633. ↩︎
Dobzhansky T. 1965. Mendelism, Darwinism, and Evolutionism. Proceedings of the American Philosophical Society 109: 205–215. ↩︎
Thoreau’s woods: Willis CG, Ruhfel B, Primack RB, Miller-Rushing AJ, Davis CC. 2008. Phylogenetic patterns of species loss in Thoreau’s woods are driven by climate change. Proceedings of the National Academy of Sciences 105: 17029–33. Leopold’s shack: Bradley NL, Leopold AC, Ross J, Huffaker W. 1999. Phenological changes reflect climate change in Wisconsin. Proceedings of the National Academy of Sciences 96: 9701–9704. ↩︎