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and trees talk to each other beneath the soil. This forest holds a magic so potent, it can tame wild beasts, join forces with predators, and ultimately determine the future of our entire planet. This is the story of our boreal forests. Take a journey through our planet's kaleidoscope of forest realms. to the tropical jungles that hug our equator, from mountain peaks to the ocean depths, marvel at the magic and drama that unfolds as we reveal the secrets of the enchanted forests.
In the far northernmost reaches of our planet, on the edges of the Arctic Circle, a swathe of evergreen forest wraps around the Earth like an emerald crown. named after Boreas, the Greek god of the harshest of winds. This wild and brutal realm is home to the reindeer, an icon of the boreal snowscape. These Arctic specialists are equipped with seemingly supernatural abilities, enabling them to conquer their frozen world.
The reindeer have spent the winter months among the trees. Soon, this heavily pregnant herd must leave the forest's protective embrace They have 3 weeks to reach their birthing grounds, hundreds of kilometers away in the mountains. But before they leave their wooded sanctuary, they must build up their reserves. Beyond the forest, the reindeer's passage across the tundra There will be little to eat here during wintertime. But within the trees, the conditions are just right to grow a precious superfood, This exquisite combination of fungi and algae creates the perfect blend of nutrients and carbohydrates to fuel the reindeer on their journey.
The trees act as willing hosts to the lichen in return for a powerful, life-giving substance captured from thin air. Lichen spins nitrogen from the atmosphere into a form that the trees can absorb. Much of the lichen lies shrouded in snow, but that's not a problem for the reindeer. They have evolved a special kind of vision. Their eyes see a spectrum of light that few other mammals can see. Anything that absorbs ultraviolet light from the sun appears black to the eyes of the reindeer, even when it's buried under the snow.
All they need to do is uncover this hidden bounty. With reserves replenished, the herd begin their exodus to their summer pastures. Without the protection of the forest, the pregnant reindeer are now exposed and vulnerable. Now that the reindeer are out in the open, the forest's allegiance has shifted. The trees that once offered the herd protection now provide cover for the enemy. This pack of wolves is poised for an ambush. But their pale fur, their secret to blending in against the snow, is rendered useless when it comes to outsmarting reindeer.
Their coats absorb UV, just like the lichen. In reindeer vision, a wolf stands out as a black shape against the white snow, eliminating any chance of a surprise attack. The reindeer's superpower vision gives them the edge in this wintery realm and sets them apart from every other species of deer. It feeds them and ensures a safe passage for the herd and the unborn calves they are carrying. Finally, after a perilous 240 km, these reindeer have arrived exhausted, but safe.
A nutritious banquet of herbs, grasses, and sedges now awaits the hungry herd. This marks the start of new beginnings. The newborn calves will fatten up on the tundra, their summer paradise. Within a few months, they'll have gained the strength to accompany their mothers on the return journey home. Back to that same boreal forest that has sheltered the herd for generations. They'll need its shielding embrace if they're to survive their first winter in the frigid north.
These evergreen trees, draped in their winter finery, are as far north as trees get. Their ability to survive here is nothing short of miraculous. Their classic look and graceful shape belies their true grit. [bell] Each trademark characteristic, each minuscule detail, has evolved to take on the Arctic's icy powers. For some of these evergreens, 100 years might bring only 20 cm of growth. Height isn't the goal for these trees. Instead, it's shape and substance that really matter. The trees' leaves, or needles, are dark and narrow, designed to absorb as much of the weak winter sunlight as possible.
Their waxy texture helps retain what little liquid water there is. Inside, special proteins work as an antifreeze, keeping the trees' internal mechanisms functioning when temperatures drop well below zero. And that's classic Christmas tree shape we know and love is there for a reason. so any heavy bouts of snow simply slide off. unbroken, and unrelenting, these trees are the hardcore tough guys of our boreal forest. For most, winter is the toughest period of all in a boreal forest. But for one tiny resident, it can't last long enough. During the long, cold season, a blanket of thick snow carpets the entire forest floor. For this deer mouse, it's his favorite time of year.
He is at the bottom of the food chain in this forest and lives his life in hiding. But in winter, the forest gives him a helping hand. Beneath the hardened snow, undulating tree roots and shrubs form air pockets, creating a labyrinth of mouse-sized tunnels. Down here, it's much warmer, and any sounds he makes is muffled by his icy walls. He has plenty of roots and stems to feed on and can happily stay stashed away all season.
The only thing his bunker lacks is fresh air. So, he must make sure his home is well ventilated. But in this forest, an open door is seen as an invitation. This pine marten uses his keen sense of smell to locate the mouse's burrow. The mouse uses the tangle of tunnels to outwit his pursuer. All it takes is one wrong turn for the marten to come out empty-handed. Safe for now. But when spring arrives, everything changes.
The forest's cloak of protection melts with the snow. Now, a mouse's every move, every sound, is music to the ears of nearby predators. And there is no longer anywhere for them to hide. For the great gray owl, this reversal of fortune couldn't have come at a better time. Their newly hatched chicks will be raised on a diet of the now exposed mice and voles. The change in season has drastically altered the playing field. Now, these aerial predators hold the power. But maybe not for long. As the days warm up, ground plants will begin their short growing period, and the forest will once again be able
to provide just enough cover for all their ground scurryers. As long as they keep quiet. There's more than one hidden labyrinth in this forest. Beneath the soil lies an even greater network of connections. A secret place where trees talk, share, and sometimes even try to poison each other. Trees may appear as silent, impassive sentinels, but underground lies a very different story. The trees' roots are plugged into a vast web of fungal strands, The fungi provide the trees with nutrients absorbed from the soil. And in return,
the trees feed them sugars. But, the trees are using this wood-wide web for a far greater purpose. Using their own social network, older, more robust trees can send food and water to those in need of a boost. They even use this underground matrix to protect each other from harm. Distress signals are dispatched through their roots to warn surrounding trees of impending dangers, triggering them to launch their own internal defenses. These seemingly selfless exchanges are life-sustaining. But, like our own internet, the forest has a dark web where users exploit the system for their own selfish gains.
Bilberry plants maliciously spread toxins, sabotaging their rivals in a quest for more light and space. And others, like this orchid, use these connections to steal food from their neighbors, offering nothing in return. But, for the majority of trees, this vital partnership turns a group of individuals into a thriving woodland community. Even the quietest forest is as bustling as a city, just under the surface. At the southerly edge of the boreal forest, the dominance of the pine tree starts to wane. Here, species such as birch and aspen are welcomed into the boreal family, and could even be responsible for turning a top predator into a teddy bear.
Just south of the Canadian border, some wide-eyed residents are out exploring for the very first time. The lives of these playful cubs will be shaped by their forest environment, Their whole character has been shaped by it, too. Could it be that a black bear's tree-dwelling lifestyle has made them less aggressive than their brown bear cousins? Caring for vulnerable cubs is the ultimate test of a bear's personality. Over the next few years, this bear mom will devote her life to raising her little ones. There are two pressing life skills that she must teach them.
The first is to find food wherever you can. Like all forest dwellers, bears know that the best food is seasonal. In this mix of broadleaf and pine forest, they couldn't be better provisioned for. Non-native dandelions are a particular favorite. Highly nutritious, succulent, and easy for a young bear to digest. But, their picnic is about to be interrupted. This lone male has picked up the family's scent. At this time of year, he is only concerned with two things: food and mating.
He wouldn't hesitate to kill the cubs if it meant he could breed with their mom. So, mom distracts the determined suitor, giving her cubs the time to implement their second life skill. Climbing. Within seconds, the cubs are out of immediate danger. And mom can calmly deflect any unwanted attention without a fight. Black bears are incredibly adept climbers. Their curved claws, strong forelimbs, and comparatively small size mean they can find sanctuary or a playground amongst the trees.
Unlike their larger brown bear relatives, who prefer to keep their feet firmly on the ground. Their temperaments are very different, too. Brown bears prefer the richer food sources of the open prairies and meadows. So, when a brown bear faces a threat, with nowhere to hide, their only option is to stand their ground and fight. Whereas the black bears stick to the forest, where cubs can flee to safety and mama bear can afford to be a little more relaxed.
Each species of bear has developed a different approach to protecting their family based on their chosen habitat. By sticking to the forest with its easy escape routes, black bears don't have to be as aggressive in the face of danger. Here, amongst the trees, the best mothers prove to be the climbers, not the fighters. If the boreal forest wields enough power to placate a bear, what could it do for us? When you wander through a pine forest, you can be forgiven for thinking there's magic in the air. The scent of pine not only smells great, but it can also influence the weather, and improve our own physical and mental well-being. That distinctive pine fragrance is made from special compounds known as terpenes in the trees resin.
But that heady aroma is merely a byproduct. On hot, sunny days, these terpenes are released into the atmosphere. The tiny floating particles refract and scatter the sun's rays in all directions, ensuring the sun hits as many of the trees needles as possible, doubling their chance of capturing its energy. And if it gets too hot, the particles can also react with rising water vapor, conjuring up clouds, and providing the forest with its own bit of shade. Collectively, the trees are changing the Earth's atmosphere to suit themselves. Stretching out into the breeze, pine needles dramatically increase a tree's surface area.
Thousands of needles act like a giant air conditioning unit for the north, trapping pollen and pollutants on their surfaces, and absorbing dangerous gases through their pores, filtering the atmosphere in the process. It's so effective that every year, 2 and 1/2 square kilometers of forest can remove up to 20 tons of particulate matter. As we inhale that clean, pathogen-free air, we are also receiving a dose of complimentary medicine straight into our lungs. The terpenes produced by coniferous trees are proven to reduce inflammation, increase antibodies to fight off disease, and ease stress and anxiety. So, take a deep breath.
A walk in these woods has never felt so good. A living pine needle may hold magical healing properties, but a dead pine needle is just as useful to the boreal forest's own dedicated team of miniature eco-warriors. At the height of the boreal summer, mysterious mounds rise up from the forest floor, as if an industrious force has swept the debris of past seasons into uniform piles. And these are their carefully designed, fully sustainable, zero-waste homes. These ants recycle the forest's leftovers to cater to their every need. As cold-blooded creatures living in the cooler, high latitudes, they must work hard to keep their home well heated. So, they use solar power.
The ants build their nests facing southwards, and precisely angle their sides so they can maximize any warmth from the sun's rays. They also use their bodies as mobile solar panels, warming themselves before entering to maintain a cozy, optimum temperature of 30° C, perfect for incubating the next generation of larvae. But with half a million ants in the colony, if it does get a bit too hot, they just throw open the windows. It's at this time of year, with thousands of developing larvae to feed, the workers step up their search for food.
Located in the tree branches above, hordes of sap-sucking aphids secrete a constant supply of honeydew, which the ants siphon off. But this sweet infusion isn't enough to satisfy the growing larvae. They need protein. A specialist hunting party ventures out in search of prey, A single ant colony captures around 6 million prey items each year. This organic eco-home requires constant upkeep. It can get a little damp down on the forest floor, but the colony has found a clever way to deal with any outbreaks of mildew.
The ants collect surplus shards of tree resin. They mix this with their own formic acid, normally used to sting, and create a homemade antibacterial, anti-mold solution, keeping their nests mold-free and smelling fresh. There is no such thing as waste in this forest. The wood ants have built an empire out of nature's leftovers. And they've done so by treading lightly, the epitome of environmentally friendly family living. Other residents can't help but tread heavily. One of the boreal's largest is on his yearly mission to bulk up and build a set of antlers forged from salt. After a lean winter, the forest springs back to life. For this bull it's all about getting in shape.
As this year, he's keen to find himself a mate. He uses the forest like a living kitchen pharmacy. Purposefully seeking out the nutritious meals, supplements, and remedies that will help him to reach peak condition. First, he spends his days building body mass, devouring tender young saplings, tearing off newly sprouted foliage, But, beefing up is only a part of the job. To really impress the females, it's all about his antlers. Antlers are made from fast-growing bone. They expand at the rate of 3 cm a day, and are fueled by large quantities of salt. To find this vital mineral, he leaves the trees and heads to the ponds. As aquatic plants contain 500 times more sodium
than any land plants. And to give him an extra edge over his rivals, he ventures out on the highway. He's learned that the roadside vegetation here has been sprayed with salt by the gritter trucks throughout the winter, providing a sneaky boost for his growing rack. By the height of summer, his double-layered fur coat covering his now muscular frame makes this an uncomfortable time of year. Moose do not sweat, so he splits his time between chilling in the meltwater pools which he now needs to strengthen his new antler growth.
By the time autumn arrives, the benefits of his carefully balanced diet have paid off. He and his antlers are in tip-top condition, ready to warn off rivals and impress potential mates. Well, they would be if he could find a female interested enough to fight over. his mating season has been woefully uneventful. He discards his precious antlers to save energy over the leaner winter and heads into the hills. Up here, he targets sapling bark and needles, as they're far sweeter than the old-growth pines. But, once denuded of their protective outer layer,
the young trees are unable to recover in the cold. To fuel their seasonal demands, moose are gradually transforming the face of this forest. Every sapling eaten means one less tree. And a forest needs to regenerate to survive. It's an age-old balancing act between healthy growth and hungry residents. To help maintain that balance, the forest needs an ally. There is a special group of animals that can counteract a moose's voracious appetite. And in doing so, can revive the forest and even the planet. In the dead of winter, herbivores will consume every last bit of sustenance a tree has on offer.
But, too many mouths browsing in one place can devastate a tree beyond repair. And there is one thing that never fails to get them moving. Predators. Their presence casts a spell over the forest, creating a landscape of fear. Herbivores are forced to live their lives on the run. This fear of getting caught helps the forest. A fleeing herd spreads its grazing further afield, giving plants and trees the respite they need to recover. And the predators' own need to feed means fewer mouths for the forest to support.
This predator-prey relationship could even be part of the solution to some of our man-made problems. In North America, a boreal forest with wolves can capture more harmful carbon from the atmosphere than one without. Their presence can be likened to removing the emissions of 71 million cars from the roads every year simply by chasing their prey. Far from being the bad guys, these predators contribute a great deal more to life on Earth than they take. The boreal ecosystem in perfect harmony is a powerful force. and sustenance, a wealth of opportunities, and a brighter future for our planet.
