Marit Ekland on plot 7 of the Haldor Wood, one of 12 she has walked every autumn since 1986. Engraving by Ottilie Marsh
Marit Ekland counts mushrooms on her knees. She is 79 and the knees are not what they were, so she carries a square of foam cut from an old camping mat and drops it onto the moss before she kneels. On a wet Wednesday last October, in the Haldor Wood above the village of Skelby, she settled onto plot 7—a patch of spruce and birch 10 meters on a side, marked at its corners by aluminum tags nailed to stumps—and began, without hurry, to look. Chanterelles under the birch, 14. A brittlegill the color of raw beef, three, two of them slug-eaten. A fly agaric, single, its red cap flecked with white and gone flat at the edge like an old umbrella. She wrote each one in pencil in a school exercise book: date, plot, species, count. The book was the 40th of its kind.
She started in October 1986, when she was 39 and teaching the nine-year-olds at Skelby’s primary school. She had taken them into the wood to draw mushrooms, and one boy asked whether there were more of them than last year. She didn’t know. Neither, she discovered when she asked around, did anyone else. The region’s naturalists kept lists of which species had been seen where, but nobody had counted the same patch of ground year after year. On Sunday, October 5, she went back alone with a tape measure, a ball of string and a bag of tent pegs, and laid out 12 plots along the path the class had walked. “I thought I’d do it for a few years and then tell him,” she said. “I never got round to telling him. I kept counting.”
Erik Lindqvist is a science writer covering climate, ice, and forests, usually from somewhere without a phone signal. He spent five summers as a field assistant on glacier surveys in the northern ranges and two winters as a forestry inspector before writing The Snowline Moves Uphill, an account of a decade of fieldwork on a single mountainside. He lives in Norhaven, where he skis to the post office from December to March, and he writes his field notes in pencil because ink freezes.
Its telescope is a century old and its funding runs out in March. Its astronomers are using the time they have left to finish a sky survey begun in 1931.
Because she began in October, her first season has no beginning; whatever fruited in September 1986 went uncounted. From 1987 on she set herself rules and kept them. She walks the plots twice a week, on Wednesdays and Sundays, from the first of September until the first hard frost, which these days can come as late as December. In the Ekland household, all of this is called October. She records every fruiting body she can identify and draws the ones she can’t. In 40 autumns she has missed 14 visits: nine for a new hip in 2011, three in the week her husband died, one for a snowstorm in October 1992 that she still regards as unreasonable, and one she cannot account for and which bothers her.
Forty notebooks
The notebooks, ruled into columns by hand, the early ones with pressed moss still between the pages, fill most of a shelf in her kitchen. Together they hold about 1,000 visits, 212 species and 48,312 individual counts. For most of their existence nobody but Ekland read them. In 2018 she wrote a 300-word note for the bulletin of the Norhaven Field Club, under the title “Mushrooms Late Again,” observing that her chanterelles seemed to arrive later than they used to. Hanna Weller, a fungal ecologist at the University of Corran, read it on a train. “I got to the line where she mentioned 32 years of counts on fixed plots,” Weller said, “and I got off at the next station.”
Fungal records are notoriously hard to come by. Most of a fungus is a web of fine threads, the mycelium, spread through soil, wood or the roots of trees, invisible and largely unmeasured. What we call a mushroom is its fruiting body, put up for a few days to scatter spores, and whether it appears depends on that year’s rain, temperature and a dozen other things nobody fully understands. One autumn’s count says almost nothing. Forty autumns on the same ground begin to say a great deal, because the noise of individual years starts to cancel out and leave the trend behind. “Professional ecologists work in three-year grants,” Weller said. “Fungi work in decades. Marit was the only one of us on the right timescale.”
Marit was the only one of us on the right timescale.
— Hanna Weller
Weller’s group spent two winters turning the notebooks into a database, and much of that time went into deciding what not to use. Ekland’s skill grew over the years; she can now name species she would have drawn as “small brown, gills crowded” in 1990. Counting newly learned species as new arrivals would make the forest look richer than it had become, so the analysis rests on 31 species she identified with confidence in her first full season, checked against her drawings. Plot 4 was dropped after a clear-cut in 2003, and plot 9 after a storm in 2011 laid half its spruces flat.*
What the fungi are saying
The central finding fits on a single line of Ekland’s handwriting, repeated 40 times. In the first five autumns of the record, the main flush of mushrooms began on average on September 15. In the last five it began on September 28, about two weeks later, and in 2023 it held off until October 2, the latest date in the notebooks. The end of the season has moved too, from late October to the third week of November, so the fruiting season has not merely shifted but stretched a little as it went. Over the same four decades, the average September temperature at Norhaven’s weather station has risen by about 1.6 degrees Celsius.
When the autumn flush begins in the Haldor Wood, 1987–2025
First visit each autumn on which at least three of Marit Ekland’s 31 indicator species were fruiting, shown for every second year. Zero is September 1; the latest on record, 31, is October 2, 2023. The trend is a little under four days later per decade. Source: Marit Ekland’s field notebooks, digitized by the University of Corran fungal ecology group
Weller’s working explanation is that many forest fungi wait for a cue before fruiting—soil cooling after the summer, together with enough rain to swell mushrooms that are mostly water—and that the cue now arrives later. The species that partner with tree roots, trading minerals for the sugar the trees make, shifted further in Ekland’s record than those that rot dead wood and leaves: by 17 days against nine. That fits a second idea, that these partner fungi build their fruiting bodies from sugar supplied by their hosts, and that the birches and spruces of the Haldor Wood are staying active later into warmer autumns. “That’s a hypothesis,” Weller said. “Marit’s notebooks are evidence. I try not to confuse the two in front of her.”
Ekland took the main result calmly; she had written “late again” in the margins of nine of her last 12 notebooks. What upset her was a finding that had nothing to do with the calendar. In the early years, the commonest mushroom on her plots was a small orange waxcap that grew in the mossy clearings of plots 2 and 3. As young spruce filled those clearings in, its numbers fell by 80 percent, a reminder that not every change in a forest is written by the climate. “That one I took personally,” Ekland said. “I used to have to step around them.”
Whether two weeks matters depends on who is asking. For the foragers who drive up from Norhaven on September weekends, it means an empty basket where there used to be a full one. For the forest, the stakes are harder to see. Fruiting bodies feed slugs, beetles, flies, squirrels and deer, and some of those animals keep calendars of their own; a flush that arrives after the first frosts may be one that some of them miss. Similar delays have turned up in long fungal records elsewhere in northern Europe, many of them also kept by amateurs. “People talk about citizen science as if it were a junior kind,” Weller said. “Some of the longest ecological records we have were kept by schoolteachers, parish clerks and people who couldn’t sleep. What they have that we don’t is stubbornness.”
The next walker
Ekland does not intend to stop, but she has made arrangements. Since 2020 she has walked the plots on Sundays with Jens Aune, a 49-year-old forestry worker who lives in Skelby and spends his weekdays driving a harvester through the kind of spruce stand her plots sit in. He was in her class in 1986. Ekland is certain he was the boy who asked the question. Aune is not. “I remember the bus,” he said. “And that she made us wash our hands twice.” He now identifies all 31 indicator species reliably, and Ekland has checked his counts against her own for six seasons. They differ, she says, by about as much as she used to differ from herself.
When I walked the plots with them last October, the day ended on plot 12, at the edge of the wood where the spruce gives way to a hayfield. Aune called out the counts and Ekland wrote them down: chanterelles, nine; ochre brittlegill, 22; a single hedgehog fungus, its underside bristling with soft, pale spines. Then she ruled a line, wrote the date and closed the notebook. The 41st is already on the kitchen shelf, still in its plastic wrapper. She will open it on September 1, and she expects, on current form, to have nothing to write in it for about four weeks.
Notes
*H. Weller, M. Ekland and colleagues, “Four Decades of Fruiting on Fixed Plots in a Boreal Mixed Forest,” Northern Fungal Studies, 2024. The start of the autumn flush is defined as the first visit on which at least three of the 31 indicator species were found fruiting on the 10 remaining plots, so that a single early mushroom cannot set the date. Fruiting dates were compared with daily temperature and rainfall from the Norhaven weather station. ↩
