“Forests are a natural ray of hope”

The forest reserve is easily accessible on foot and is located a three-kilometre walk from Groenendaal Train Station. At first, only the information board and barrier reveal that you are entering the (public) reserve. If you look closely, you’ll see that the saw hasn’t been used here for forty years. Deadwood is no longer collected. On the left, a fallen tree leans shamelessly against another tree. The final collapse seems imminent, but it will take ten years. On the right we see a tree that found the forest floor and now acts as a living mass for fungi and beetles. And thick, the trees here are remarkably dense (although they are already everywhere in the Sunian forest). Now in the oldest part of the forest reserve there are more than twenty beech trees per hectare with a diameter of more than 100 cm per hectare – which is very rare even in the primeval beech forests of the Carpathians of Romania or Ukraine.

Because we don’t speak the language of trees, we asked forest researcher Chris Vandekerkhof from the Nature and Forest Research Institute to act as translator. Vandekerkhove guides us to the largest and largest beech tree of all, a stout lady measuring 46 meters high and five meters in circumference. During the salute, Chris and I didn’t have enough arms to hug the tree. This requires at least three adults (with long arms). This tree cathedral is likely one of the largest beech trees in the world. Beech has no name, which hinders smooth conversation. That’s why we named the tree itself: Sophie, the name of the most popular girl in Belgium in 1983, the “birth year” of this forest reserve.

Hi Sophie. Merry Christmas from your home. What have the last 40 years been like?

‘In general very nice, and above all very quiet. There will be no more saws or heavy machinery here. Because of all this wood allowed to continue to grow and lie, there are now approximately nine hundred cubic meters of wood per hectare. This is almost four times what is found in an average forest in Flanders. After forty years without management, the reserve has reached a status similar to that of a primeval forest. This is exceptionally fast.

“More dead wood and more structure is a boon for the forest and the biodiversity that lives here. The Sonian forest is home to no less than five different species of woodpeckers. Rare bats, insects, spiders, mosses and amphibians live there. The wealth of fungi is enormous. So far it has only been described More than a thousand species of mushrooms in the forest, most of them rare and endangered. The famous wig fungus has returned and may be growing here for the first time in more than a hundred years. We doubt it because mycologists a hundred years ago never mentioned the wig fungus found in the Sonian forest. While you can’t ignore it: It’s literally a big white wig hanging from a tree. Wild boars have recently begun moving around in the Sunian forest. This one is special. Although they often appear in the media as pest species, the wild boars here ensure that order The forest ecosystem is more complete. They dig into the soil, and in doing so also plant seeds in the ground such as acorns, which can then germinate.

The reserve is forty years old, but how old are you and the other veterans standing here?

“I am one of the oldest living beech trees.” I estimate I am about 250 years old. There is also an oak tree here, perhaps 300 years old. It sounds like a lot, but I, like the other ancient trees in the reserve, still glow with health. The fact that the trees here are allowed to grow completely freely, and they do, surprises even scientists. Experts used to assume that the maximum age of a beech tree was about two hundred years. ‘They were wrong.’

The Sunian Forest is one of the few large forests with fertile soil that has survived over the centuries. Most of the forests have disappeared to make way for farmland. We were lucky because this forest has always been a hunting place for the rulers of this region. They prevented their playground from being cut. From 1850 onwards, wealthy residents of Brussels came to picnic here as well. They were shocked when the trees were cut down, and used their long arms in the political world to protect the Sunian Forest. As a result, many trees that would normally have been cut down around the centenary for use in furniture remained standing.

“In 1983, the then technical director Joseph Zwennipoel decided to leave the patch of forest in which I was standing unmanaged. In fact his bosses had little interest in it. The Sonian Forest is home to beech trees with perfectly straight trunks, which means high quality. Cutting down trees is equivalent to throwing away a small fortune. Zwenpoel insisted on this stubbornly and played it tactically. He did not ask for two hundred hectares, but twenty. On a total area of ​​five thousand hectares, this was quite acceptable. In the years that followed, parts were gradually added, Since 2010 the reserve has grown to 230 hectares.

Are there still unmanaged forests in Flanders?

“About three thousand hectares of forest officially have the status of unmanaged forest. This is approximately two percent of all forests in Flanders. You will no longer find true primeval forests in Flanders, but ancient, densely wooded forests can be found in reserves in Zoniënwoud The Meerdaalwoud, Wijnendalbos in Torhout and in Grotenhout, one of the oldest forests in Kempen.

Three thousand hectares out of one hundred and forty thousand. That seems very little.

“That’s true, but it’s not that we consider tree-managed forests to be inferior. People always manage forests for a purpose. Timber production is common, but you can also manage a forest based on nature’s goals, such as combatting alien species or increasing diversity among trees. Recreation, carbon storage or air purification could also be a goal.

“Even in managed forests, management is now done as much as possible in line with what nature itself would do. Therefore, the average forest has more massive trees, more dead wood, more native tree species, and greater diversity than before. Forests are more stable and resilient. If there is good news to be reported anywhere in nature, it is in our forests. Various plant and animal species benefit from natural management. Birds that need cavities in old trees to breed, such as the tawny owl and the woodpecker The less-spotted woodpecker, the black-spotted woodpecker, is improving. The Middle Spotted Woodpecker, which was extinct in Flanders, has now returned to better-developed deciduous forests. Fungi and beetles that depend on dead wood are also doing well.

“These are many hopeful things, but trees do not grow in the sky. People still do not fully appreciate forests. Flanders, for example, has many valuable forests that do not have any form of protection. So in theory they could be cut down.” These forests.

What’s cut has to be made up for somewhere else, right?

“It’s crazy that you can cut down an old forest, as long as you plant some trees somewhere else. Old trees are very valuable. Even a tree that is declining or dying is more valuable from an environmental point of view than a young sprout. The storage of carbon in the vegetation and soil in A new forest does not reach the level of storage of an old forest until more than a century has passed. Biodiversity recovery often takes longer. Respect for ancient forests should become greater and more visible. Antwerp Cathedral will not be demolished to compensate for the installation of three bus stops in Schöten, Alice like that?

What is the impact of climate change on forests?

“Reports are circulating about the doomsday of us beech trees, and that climate change will herald our complete demise. You can also see this horribly illustrated here and there, for example in the bare beech lanes next to the highway between Bruges and Ghent. I admit it looks alarming. However, I do not entirely share this pessimism. Here in the Sonian Forest, the beech trees look healthy even after a hot, dry summer. The beech forest has a cooler microclimate thanks to its dense canopy. The trees on the edge, along the Brussels Ring Road, for example, face , has a hard time, because they’re not being cooled and kept out of the wind by their peers. So those trees fall more easily. So it’s not a good idea to cut beech trees out of the forest because they won’t be able to withstand climate change. You’re creating openings in the forest that heat up and dry out more quickly And it causes problems for the rest of the forest, tree by tree.’

“At the same time, I’m also holding on to my tribe for what the coming years will bring. I don’t know how the forest will react if droughts occur too often. In general, trees show clear symptoms of stress. For example, Norway spruces are literally falling with forests all over the world. Across Europe, a beetle, the letter beetle, is attacking trees. In fact, the beetle is not the problem. This insect is found naturally in these forests, and the trees can adapt to it naturally. Years of severe drought have depleted Norway spruce trees to the point that they are now It succumbs to the attack of spruce.Common ash, elm and even common pine, species that we considered almost indestructible, also weaken during drought years and are therefore less resistant to disease.

“Not only is the lack of rainfall a problem, but also the excessive pumping of groundwater for agriculture or to drain construction lands. Even after long periods of rainfall, the groundwater sometimes remains very low, which is abnormal. Trees that cannot search Deep enough from the water its roots have problems.’

Is nitrogen pollution also a problem?

‘certainly. The forest floor is becoming increasingly acidic due to nitrogen falling to the ground. Some plant species thrive on this nitrogen, but in doing so it suppresses all other plants. Nitrogen also affects forest resistance. Trees grow better because nitrogen is a fertilizer, but they invest so much energy in growing that they are less resistant. This makes trees more susceptible to diseases and pests. Soil fungi also disappear due to acidification, which also affects the underground fungal network that protects tree roots and helps them absorb water and nutrients.

There is a lot to be done about these secret networks, called mycorrhizae. Is it really the Internet of Trees or not?

American forest ecologist Susan Simard showed that the roots of ancient trees are connected to other trees in their environment via an underground fungal network. She pointed out that nutrients are exchanged between trees through mycorrhiza. So much for science. The story then veers a bit off course by humanizing the trees, as if the ancient mother trees care for the young through the network, and that they do so actively, consciously, and even form peaceful communities. This interpretation is the result of this humanization, and it has certainly not been proven in this way by scholars. It may simply be the process of connecting vessels, where water and chemicals can spread quickly through the network. For example, when deer eat a tree, that tree also produces stress-related molecules. Other trees can absorb these molecules through the underground network and respond by producing bitter substances. You can see it as a conscious signal from one tree to another, but it’s just chemistry.

The reserve in which it grows is also a popular place for scientific research.

‘Yes, of course. Unmanaged forests are essential for studying all types of processes, without the influence of human intervention. For example, the question “Are more trees dying today than before?” It can only be answered in an unmanaged forest. In managed forests, your measurements are disrupted because, for example, more trees are cut down in one year than in another, affecting growth in the forest. Then you won’t be able to see the forest from the perspective of the trees, so what are the consequences for management, what about climate change or nitrogen pollution? The knowledge that scientists gain here in the reserve therefore forms a reliable basis for managing other forests alongside nature.

Sophie, thank you for the conversation and we wish you many healthy years with your neighbors here in the woods.

‘You’re welcome, you’re always welcome for a walk. Until Sunday?’