A Wageningen University Research Visit to Sweden’s Forests
By Annabel Burg, Sietse van der Woude, Maximilian Schulte, Linus Bockenhoff, Johannes Reiche, Gert-Jan Nabuurs; and photos by Sietse van der Woude
On the morning of Sunday, we had finally arrived in Umeå. The trip had been months in the making: a research exchange between Wageningen University & Research (WUR) and the Swedish University of Agricultural Sciences (SLU), woven into a packed week of field visits, industry meetings, and policy discussions stretching across the country. By the end of the week, our group of six (Gert-Jan, Maximilian, Annabel, Linus, Sietse, and Johannes) would cover roughly the length of Sweden, from the boreal forests of Umeå in the North to the mixed woodlands near Gothenburg in the South. And we exchanged on several projects where we collaborate with EFI: from Wildcard to FORWARDS and Monifun.
Why Sweden? Sweden is one of European countries with the largest forest sector, as well as forest cover, representing around 70% of the country’s land area. The dominant species, Norway spruce (Picea abies) and Scots pine (Pinus sylvestris), have been intensively managed for many decades, and the forest sector is a cornerstone of the Swedish economy, providing raw material for everything from paper and packaging to construction timber and bioenergy. And this is why fierce debate surrounds what those forests should represent, and how they should be managed. Should they serve mainly as carbon sinks, biodiversity refuges, or be a mere source of timber and other renewable resources? That tension, among other things, is what drew us here
Day 1: Arriving in the North
Travelling to Sweden in early March from the Netherlands feels a bit like turning back the seasons. Back home in the Netherlands, the first signs of spring were finally appearing while in Sweden, we saw a landscape still in its winter slumber: dark conifers, ice-fringed lakes, and snow-patched clearings as far as the eye could see.
The journey began with the university city Umeå, which would serve as our base for the first half of the week. Umeå sits along the Umeriver, roughly halfway between Stockholm and the Arctic Circle. Known as the City of Birches, its wide avenues are lined with 2,300 birch trees planted as firebreaks after a devastating fire in 1888. Umeå has a particular energy that comes from being both a young, student-filled city and a place deeply embedded in forest culture. It felt like exactly the right place to start a week at the intersection of forests, science, and industry.
The schedule was packed: a full scientific seminar the next morning, field visits to restoration sites, visiting a sawmill, meetings with the Swedish Forest Agency, and a long drive South to meet forest owners and industry representatives. Rest first, though. The forests could wait until morning.
Day 2: “Woodpeckers” – visiting SLU and a forest restoration site
The day started with an early morning 40-minute walk to the SLU campus, or rather, a 40-minute ice slip. The pathways were frozen solid, and while the locals glided past on spiked shoes without breaking stride, we spent most of it trying not to fall. At SLU, we were welcomed by Ruben Valbuena, professor of forest remote sensing and one of the key organisers of the exchange on the Swedish side. The seminar that followed brought together eight presentations from both WUR and SLU, covering a wide range of topics: on the WUR side these were Sietse’s Sentinel-1 radar-based disturbance alerts, Maximilian’s EFISCEN-Space forest resource modelling, Annabel’s work on precision enhancement of national forest inventory estimates, Linus’s analysis of European forest maturation, and on the SLU side, research on change detection in satellite imagery, forest planning under climate change, and operational clearcut detection. It was a morning that showed just how much common ground exists between our work at Wageningen and SLU.
After an amazing lunch at SLU, it was time to leave the screens behind and head into the forest. Johan Svensson and Therese Lofroth, both researchers at SLU specializing in forest restoration and conservation ecology, along with Marlene Olsson, a PhD student at SLU and Umeå University working as a conservationist at Umeå Municipality, took us to a restoration site along the Ume river, that was part of the SUPERB project (2021-2025). The site is dedicated to broadleaf restoration and veteranization: the deliberate creation of old-growth characteristics in managed forests, such as retaining veteran trees, creating deadwood, and fostering the kind of open structural complexity that species like white backed woodpeckers depend on. We were eager to hear the woodpeckers but then understood that forest practitioners who had been in the field many early mornings, had only heard their sounds a few times. However, we learned that the very small population of white backed woodpecker is doing good.
Johan also took us to his own farm, where he practices selective thinning from above, gap cutting, continuous cover forestry (CCF) and tree species diversification. These approaches move away from even-aged monocultures towards more structurally diverse, resilient stands. But the visit came with a sobering reminder of the pressures these forests face. Storm Johannes, which swept through Sweden in 2025, had left its mark here too, with significant blowdowns of especially the large trees that Johan had left standing in the CCF, visible across stands that had been carefully managed for years. It was an illustration of the tension between long-term ecological ambition and the increasingly unpredictable forces bearing down on Europe’s forests.
Day 3: “Woodcutters” – Visit to Norra Skog, harvest sites and sawmill
Our third day was the ‘woodcutters’ day, which was all about the timber Sweden’s forests produce and the people and machines behind it. A short walk from the hotel brought us to the headquarters of Norra Skog, one of Sweden’s three large forest owners’ associations. Lina Arnesson, a PhD candidate at SLU, gave us a warm welcome and a frank overview of the association’s work and on the perspective of the forest owners themselves. From there, we headed out to a harvest site, where a harvester and forwarder were working their way through a stand with remarkable efficiency: the smell of fresh-cut wood hung thick in the cold air. For some of us, it was the first time seeing this kind of machinery in action up close. The technology is impressive: a harvester can fell, delimb, and cut a tree to length in a matter of seconds. After the previous day’s restoration site, the contrast could not have been sharper. Similar forest, different philosophy.
The afternoon brought a visit to a sawmill operated by NorraTimber, where we received a direct insight to the value chain of the Swedish forest industry. What struck us most was the technology running behind the scenes: each log is scanned using X-ray imaging as it enters the mill, allowing the software to map the internal structure of the wood and calculate the optimal cutting pattern to maximise timber value. It was a neat illustration of how much precision and investment sits behind what looks, from the outside, like a rather straightforward industry.
The day ended on a more relaxed note: a sauna by the river, followed by a dip in the icy water. Some of us took to it more enthusiastically than others.
Day 4: Moving towards Central Sweden
Leaving the Boreal North behind we moved towards the landscapes of Central Sweden. We made our way to Uppsala with just enough time for a quick walk through its historic university campus before meeting Jeannette Eggers and Ragnar Jonsson at the Ultuna Campus. Our conversation centred around forest resource modelling: their Heureka model, a forest analysis and planning tool developed specifically for Swedish forestry, and our own EFISCEN-Space model, which takes a broader European perspective. Comparing the two approaches, one deeply rooted in national management practice, the other built for continental-scale policy questions, made for a rich and honest exchange about what each can and cannot do.
By late afternoon, we were back on the road inland to Dalagård, a beautiful farm tucked into the Swedish countryside. The drive, of course, doubled as a field validation session: Sietse pulled up his RADD alerts along the route, and the system did not disappoint, correctly identifying a recent clearcut, with the timing of different cut areas clearly visible in the data. It is one thing to see alerts on a screen in Wageningen; it is another to pull over on a Swedish country road and watch them match the landscape in front of you. Gert-Jan was totally happy with this validation — admittedly based on a sample size of just one clearcut, but a win, nonetheless.
At Dalagård, we were warmly welcomed by our hosts Cecilia and Leif Öster, and were joined by Sten Nilsson, a veteran of Swedish and European forest policy with decades of experience across academia, industry, and international institutions. Sten gave us an overview presentation starting from global affairs and then focusing on the Swedish forest sector, stating that the industry’s biggest challenge is not technical but political: changing from short-term thinking to a focus on long-term decision-making that serves both ecological purposes and societal well-being. The presentation turned into a dinner table discussion on where European forests in general and Swedish forestry in particular are heading. But the evening was not all serious. Our hosts had prepared a three-course meal to remember, capped off with a recreated recipe from 1628 — a drink called ‘Vasa 1628’, inspired from what was salvaged from the archives of the Vasa, the famous Swedish warship that sank on its maiden voyage and was raised from Stockholm harbour centuries later. It was a perfect end to a long day!
Day 5: Visiting the Swedish Forest Agency — Jönköping
Our fifth day began in the best possible way: our host Leif took us out into the forest that he owns and manages around Dalagård. It was a quiet morning walk that served as a grounding reminder of what all the modelling and policy discussions of the week ultimately connect to: individual landowners making decisions, forest stand by forest stand, year by year.
On the drive South to Jönköping, we made a small detour passing Garpenberg, where Gert-Jan once retrieved the source code of what later become the first version of the EFISCEN model. It was almost an epic moment, thinking of how much the model most of us now work with has grown since those early days. In Jönköping, we visited the Swedish Forest Agency (Skogsstyrelsen), where we met Giuliana Zanchi, a climate expert at the agency’s Policy Unit, and Anders Persson, whom we already met in the Monday seminar in Umeå. The discussions touched on both remote sensing related topics as well as on another inter-model comparison between Heureka and EFISCEN-Space.
The evening took a warmer turn when Giuliana and her husband Gerben Janse invited the whole group to their home for dinner. Gerben works at the same agency, focusing on international forest policies, and over dinner we got a glimpse of how the process of shaping EU forest policy can be, a reminder that the science we produce often has to navigate a long road before it translates into real change.
Day 6: Last field visit and going home
The week ended where it perhaps makes most sense to end: in the forest itself. Early in the morning, Anders Ekstrand, a senior forester and hardwood specialist at Södra, took us to a clearcut site near Kinna. Södra is the largest forest owners’ association in Sweden, covering the South of the country much as Norra Skog covers the North.
What struck us most was not the cutting itself, but the preparation behind it. Anders walked us through the management plans, pulled up on an iPad in the middle of the forest, which mapped out exactly which trees were to be retained, where the harvester was and was not permitted to drive, and which areas carried historical significance. Scattered across the site were remnants of old agricultural land. The harvester would work around them carefully. It was a reminder that these forests are not just ecological or economic systems, but layered landscapes with long human histories.
Looking back, what Sweden offered us was not a single answer to the question of what forests should be, but a vivid portrait of the tensions involved. From restoration sites to sawmills processing thousands of logs a day, from veteran policy thinkers at a farmhouse dinner table to forest agency staff navigating EU climate targets. The week showed us a country genuinely wrestling with the future of its forests. And through it all, one quietly reassuring fact: Swedish forests are still growing. Whatever the debates surrounding them, the trees keep adding rings.
