Big parts of Germany’s forests used to look like this. But now, they look like this. In just a couple of years, this decades-old forest has become unrecognizable. The same thing is happening in many parts of Germany, Europe and North America. "My heart aches every day when I see this." "Nowhere else in Central Europe can you experience the climate crisis like here in the Harz Mountains." "But this isn’t your typical, "the planet is dying" story. This could actually be good news." But to understand why, let’s backtrack a little bit. Or maybe more than a little bit. To the end of World War Two. A lot of the world is in ruins. And needs to be rebuilt. The Allied Forces – understandably – want reparations from Germany. But it’s broke. So they agree that country will pay partly in materials – for example, timber. Lots of timber – according to some estimates, equivalent to 10% of the country’s forests. So now, foresters need to replant big areas, ASAP – to rebuild Germany itself. And which tree did they choose? Mostly the spruce. Which, looking back, was maybe not the best decision. But at that time, it seemed like a good idea. To find out why, we’re driving to Thuringia, in the center of Germany, to meet Fanny Hurtig, a forester. "Spruce is fast-growing. It regularly delivers straight, high-quality wood that can easily be processed at or sawmills, into furniture or flooring. It’s used quite widely." That’s why it's also is a very lucrative tree. German foresters planted vast areas with them. In straight rows that make it easier to get in and harvest. This practice didn’t only start after the Second World War. People had been planting evergreen trees for centuries. But the post-war shortage really kicked off the era of extreme monocultures. "This is what a lot of Germany’s forests look like. It’s all the same tree, not a lot happening on the ground, it’s kind of boring, really." Spruces are the most common tree in Germany and make up over a quarter of all forests. But that is changing rapidly. Because what made this monoculture so profitable is also what made it so vulnerable. Forests around the world are suffering – from more intense and frequent droughts, wildfires and storms, weakening entire ecosystems. And Germany is no exception. "There was this storm in 2018, followed by three, four, five years of drought. It damaged the spruces’ fine-root system so much they no longer had the strength to draw enough water out of the ground." The longer summers due to climate change mean the forests are too dry, and the trees thirsty. Especially spruce trees – they comparatively need a lot of water but their root system is quite shallow, so they can’t access reservoirs deeper down. On top of that, many spruces were planted at much lower elevations than they are native to. So they’re not adapted to these warmer, drier surroundings. Meaning that if the surface dries out – which has happened a lot recently – it becomes a big problem. While that’s not the best news for the trees or for humans, there is one little creature that loves what’s happening right now. Enter: The bark beetle. This tiny little insect has been munching its way through many of Germany’s and Europe’s forests. The bark beetle, of course, loves the bark. It bores holes into the tree and then releases pheromones to draw a mate inside. There, they reproduce and lay eggs. These tunnels are called the Rammelkammer – which directly translates to sex chamber. "A pair used to have one to two broods. Now we’re at three to four generations. That means a pair can produce up to one hundred thousand descendants." "In a year?" "In a year. It’s an insanely large number." "That’s why they just…." "Spread like wildfire, right." "Wow!" A healthy tree usually produces resin to seal up the holes and protect itself from the beetles. But thirsty, weak trees cannot. That’s why the bark beetle is having a feast. "Five years ago this area was still fully forested. If we’re standing here now and, say, last year this area was infested, this year that area could also be infested in a matter of weeks." The beetles eat away layers that transport nutrients and water. The spruces then die of thirst and malnutrition. "It doesn’t take many weeks. Just a few weeks and the tree shows signs of dying and can no longer be revived with water or anything else." The forestry has set up traps to monitor the scale of the infestation. "This is 50 milliliters. One milliliter’s equivalent to 40 beetles, so that’s two thousand beetles in this trap. And we can see the trap’s chock-full." The beetle is steadily spreading across Europe. And the hotter it gets, the more beetles will breed. What a full-scale infestation looks like can be seen in bark beetle central, which is the Harz national park in the middle of Germany, where we’re headed. "Wow... all of that is just completely gone. That looks horrible actually, it makes me really sad." Here, about 90% of all spruces are dead. The bark beetle has come, eaten, and gone. Leaving behind a region that is, quite frankly, shocking to look at. We’re meeting Roland Pietsch, the head of the Harz National Park. "Since 2014, we’ve had real droughts here in the Upper Harz. And the landscape has changed so much that huge swaths of spruce trees have been wiped out. The Harz region is hit so hard because it had a very big concentration of spruces. But for Pietsch – and many others – this postapocalyptic looking scenario isn’t a disaster, quite the opposite. For him, the bark beetle isn’t the villain. It’s actually a blessing in disguise. "The question is: What’s happening here? And what’s happening is that the old spruce trees are gone. And the forest that belongs here is coming. When you see what kind of strength, how much life is in it, it’s beautiful. It’s great and truly exciting here. The park cut down a section of the forest as a safety barrier so that the beetle will have a harder time spreading into neighboring forests. But apart from that, the national park decided to let nature be nature – and did not fight the bark beetle. And nature is indeed doing its thing. "When I came here two and a half years ago, much of this still looked dead. It takes two or three years, but then things start to come back to life. The plants spring up like you can see here." Different areas of the national park are treated differently. Some parts, where trees are springing up on their own, are left to their own devices – like this area that died off about six years ago. "In the open areas we can see pioneer tree species that are spread widely and quickly by the wind or birds. They spring up in large numbers. If you'd walk through here in 10 or 20 years you‘ll feel like you’re in a forest." Some parts need a little bit of help, meaning formerly native species that were displaced by the spruce monocultures are being planted. "We planted them because humans are impatient. Beech seeds are heavy. We could’ve waited a few thousand years, but decided against it. I think that was a good decision." The dead trees provide a habitat for insects. They also give shade and keep moisture locked in. Fungi help decompose the wood. "Wow… it’s a real sponge." "A real sponge, it holds lots of water." Dead trees release CO2 while decaying, which means overall less CO2 is sequestered by these forests. But the hope is that the new trees will compensate for that in the long term. But that’s just one part of the story. The national park is a protected area that cannot be used to produce timber anymore. But only around three percent of all forest in Germany is protected. The rest is governed by public or private foresters, for example to produce timber. And we’ll probably be using more of it, since wood can be a very sustainable and renewable building material. Managed and grown by foresters, like back in Thuringia. They need to take a different approach to the bark beetle. The trees are checked for infestation regularly. Once an infestation is found, the trees are marked. Then they’re chopped down and removed as soon as possible to halt the spread of the beetle. Leaving behind vast areas of prematurely felled trees. But also here, it’s not seen as the catastrophe it may look like at first. "It’s also a chance to build up these areas in a more structured way and with completely different tree species – to experiment with other varieties and bring them in here, if they’re suitable." To prevent something like this from happening again, the approach here is to not only bet on one tree, but on a variety of trees. "It’s like with stocks: you diversify your portfolio to minimize risk. That’s what we’re trying to do with the mixed forest, too." This is Nico Frischbier, a scientist trying to identify the forest of the future. Here are some of the candidates: First are the OGs. Beech, oak and sycamore trees are adapted to lower elevations. They can survive with less water because their root systems are deeper. But they do grow much slower than spruces. Oaks take between 120 and 300 years to be harvestable. Second are the newcomers like the Douglas fir. Native to North America, Douglas firs can also handle more heat and droughts. They grow quite fast and their wood is hard and of good quality. This type of fir is also more resistant to pests and storms than spruces. These are currently seen as good candidates. But if we continue to heat up the planet, we will need to mix in some wild cards. To find out which ones may be suitable, the Thuringian forestry has been conducting a now over ten year old experiment in the driest region of the forest. The trees come from warmer climates, but are alpine trees. Because if they want to survive here, they need to be able to handle not just drought, but also frost. So enter the Southern belles. First off the Turkish fir – which can thrive in very dry conditions and can stand in exposed areas. Its wood is also straight and similar to the spruce – but it is quite hard to plant successfully and also grows slowly. The Oriental beech is native to Southeastern Europe and the Caucasus region. It is a broadleaf tree which is similar to other domestic beech trees. It’s speciality is that it’s super flexible and can adapt well to extreme weather. The rare Lebanese cedar grows quite fast, but is also hard to plant. And there are first signs the bark beetle likes this tree too. "It's more work because in a mixed forest you have to deal with various species of trees. They each have different risks and costs, so it’s pricier all the way through to the marketing of the wood or other products. But, from our point of view, it’s worth it, because it reduces the risk. You might have more expenses and a smaller yield but, for the forest owner, it carries less risk." This type of forestry, as well as the national park’s approach, shows where a lot of international forests could be heading. "It’s also an opportunity to adapt to climate change or speed up the forest conversion, which would otherwise take much more time." "It’s good from the perspective of the climate crisis and it’s good for resiliency as well as biodiversity." The idea of cultivating a long-lasting, mixed forest isn’t new. It’s just that in times of crisis, the quickest and easiest solution was chosen. "These vast areas of dead trees aren’t the end of the forest." It’s just the end of the forest as we know it here: straight rows, tidy, fast-growing trees for profit. Even though it might look tragic, a new, better forest is already starting to grow, one that is more resilient than what we created before. And one that will hopefully weather and adapt to whatever is going to happen in the coming decades. "Thanks for watching! For more videos like this, subscribe. We post videos every Friday."
