Peter Wohlleben Quotes

When you know that trees experience pain and have memories and that tree parents live together with their children, then you can no longer just chop them down and disrupt their lives with larger machines.

An organism that is too greedy and takes too much without giving anything in return destroys what it needs for life.

If we want to use forests as a weapon in the fight against climate change, then we must allow them to grow old, which is exactly what large conservation groups are asking us to do.

There are more life forms in a handful of forest soil than there are people on the planet. A mere teaspoonful contains many miles of fungal filaments. All these work the soil, transform it, and make it so valuable for the trees.

Trees, it turns out, have a completely different way of communicating: they use scent.

If a tree falls in the forest there are other trees listening.

This is because a tree can be only as strong as the forest that surrounds it.

Every walk in the forest is like taking a shower in oxygen.

But we shouldn't be concerned about trees purely for material reasons, we should also care about them because of the little puzzles and wonders they present us with. Under the canopy of the trees, daily dramas and moving love stories are played out. Here is the last remaining piece of Nature, right on our doorstep, where adventures are to be experienced and secrets discovered. And who knows, perhaps one day the language of trees will eventually be deciphered, giving us the raw material for further amazing stories. Until then, when you take your next walk in the forest, give free rein to your imagination-in many cases, what you imagine is not so far removed from reality, after all!

Every species want to survive, and each takes from the others what it needs. All are basically ruthless, and the only reason everything doesn't collapse is because there are safeguards against those who demand more than their due.

It appears that nutrient exchange and helping neighbors in times of need is the rule, and this leads to the conclusion that forests are superorganisms with interconnections much like ant colonies.

One of the oldest trees on Earth, a spruce in Sweden, is more than 9,500 years old. That’s 115 times longer than the average human lifetime.

But together, many trees create an ecosystem that moderates extremes of heat and cold, stores a great deal of water, and generates a great deal of humidity. And in this protected environment, trees can live to be very old.

When trees grow together, nutrients and water can be optimally divided among them all so that each tree can grow into the best tree it can be. If you "help" individual trees by getting rid of their supposed competition, the remaining trees are bereft. They send messages out to their neighbors in vain, because nothing remains but stumps. Every tree now muddles along on its own, giving rise to great differences in productivity. Some individuals photosynthesize like mad until sugar positively bubbles along their trunk. As a result, they are fit and grow better, but they aren't particularly long-lived. This is because a tree can be only as strong as the forest that surrounds it. And there are now a lot of losers in the forest. Weaker members, who would once have been supported by the stronger ones, suddenly fall behind. Whether the reason for their decline is their location and lack of nutrients, a passing malaise, or genetic makeup, they now fall prey to insects and fungi. But isn't that how evolution works? you ask. The survival of the fittest? Their well-being depends on their community, and when the supposedly feeble trees disappear, the others lose as well. When that happens, the forest is no longer a single closed unit. Hot sun and swirling winds can now penetrate to the forest floor and disrupt the moist, cool climate. Even strong trees get sick a lot over the course of their lives. When this happens, they depend on their weaker neighbors for support. If they are no longer there, then all it takes is what would once have been a harmless insect attack to seal the fate even of giants.

There are more life forms in a handful of forest soil than there are people on the planet.

So many questions remain unanswered. Perhaps we are poorer for having lost a possible explanation or richer for having gained a mystery. But aren't both possibilities equally intriguing?

So, in the case of trees, being old doesn't mean being weak, bowed, and fragile. Quite the opposite, it means being full of energy and highly productive. This means elders are markedly more productive than young whippersnappers, and when it comes to climate change, they are important allies for human beings.

We have learned that mother trees recognize and talk with their kin, shaping future generations. In addition, injured trees pass their legacies on to their neighbors, affecting gene regulation, defense chemistry, and resilience in the forest community.

Fungi are in between animals and plants. Their cell walls are made of chitin—a substance never found in plants—which makes them more like insects. In addition, they cannot photosynthesize and depend on organic connections with other living beings they can feed on.

Perhaps farmers can learn from the forests and breed a little more wildness back into their grain and potatoes so that they’ll be more talkative in the future.

Perhaps we are poorer for having lost a possible explanation or richer for having gained a mystery.

Forest air is the epitome of healthy air. People who want to take a deep breath of fresh air or engage in physical activity in a particularly agreeable atmosphere step out into the forest. There's every reason to do so. The air truly is considerably cleaner under the trees, because the trees act as huge air filters. Their leaves and needles hang in a steady breeze, catching large and small particles as they float by. Per year and square mile this can amount to 20,000 tons of material. Trees trap so much because their canopy presents such a large surface area. In comparison with a meadow of a similar size, the surface area of the forest is hundreds of times larger, mostly because of the size difference between trees and grass. The filtered particles contain not only pollutants such as soot but also pollen and dust blown up from the ground. It is the filtered particles from human activity, however, that are particularly harmful. Acids, toxic hydrocarbons, and nitrogen compounds accumulate in the trees like fat in the filter of an exhaust fan above a kitchen stove. But not only do trees filter materials out of the air, they also pump substances into it. They exchange scent-mails and, of course, pump out phytoncides, both of which I have already mentioned.

The forest is really a gigantic carbon dioxide vacuum that constantly filters out and stores this component of the air.

Trees could solve the problems if people trying to improve things would only allow them to takeover

The wolves turned out to be better stewards of the land than people, creating conditions that allowed the trees to grow and exert their influence on the landscape.

But isn’t that how evolution works? you ask. The survival of the fittest? Trees would just shake their heads—or rather their crowns. Their well-being depends on their community, and when the supposedly feeble trees disappear, the others lose as well.

The trees in a forest care for each other, sometimes even going so far as to nourish the stump of a felled tree for centuries after it was cut down by feeding it sugars and other nutrients, and so keeping it alive. Only some stumps are thus nourished. Perhaps they are the parents of the trees that make up the forest of today.

Nevertheless, I have learned from this just how powerful a community of trees can be. “A chain is only as strong as its weakest link.” Trees could have come up with this old craftsperson’s saying. And because they know this intuitively, they do not hesitate to help each other out.

But the most astonishing thing about trees is how social they are. The trees in a forest care for each other, sometimes even going so far as to nourish the stump of a felled tree for centuries after it was cut down by feeding it sugars and other nutrients, and so keeping it alive. Only some stumps are thus nourished. Perhaps they are the parents of the trees that make up the forest of today. A tree’s most important means of staying connected to other trees is a “wood wide web” of soil fungi that connects vegetation in an intimate network that allows the sharing of an enormous amount of information and goods. Scientific research aimed at understanding the astonishing abilities of this partnership between fungi and plant has only just begun. The reason trees share food and communicate is that they need each other. It takes a forest to create a microclimate suitable for tree growth and sustenance. So it’s not surprising that isolated trees have far shorter lives than those living connected together in forests. Perhaps the saddest plants of all are those we have enslaved in our agricultural systems. They seem to have lost the ability to communicate, and, as Wohlleben says, are thus rendered deaf and dumb. “Perhaps farmers can learn from the forests and breed a little more wildness back into their grain and potatoes,” he advocates, “so that they’ll be more talkative in the future.” Opening

It seems the trees can count! They wait until a certain number of warm days have passed, and only then do they trust that all is well and classify the warm phase as spring. But warm days alone do not mean spring has arrived.

However, when we step into farm fields, the vegetation becomes very quiet. Thanks to selective breeding, our cultivated plants have, for the most part, lost the ability to communicate above or below ground-you could say they are deaf and dumb-and therefore they are easy prey for insect pests. That is one reason why modern agriculture uses so many pesticides. Perhaps farmers can learn from the forests and breed a little more wildness back into their grain and potatoes so that they'll be more talkative in the future.

It seems trees need their rest just as much as we do, and sleep deprivation is as detrimental to trees as it is to us.

The artificial world of the city offers all kinds of stimuli for which we were not originally designed.

Trees live in symbiosis with hyphae (fungus/mold roots). A tea spoon of dirt contains kilometers of these roots. One species can spread throughout entire forests over centuries. They exchange nutrients with trees, along with information about insects, drought and other dangers. It's like a 'wood wide web'.

Do you know what the most fun moments are? When recent graduates visit us as part of their training. They were taught exactly what the industry wants. They expect a bunch of long haired dreamers who say 'peace'. But on the first evening with them we start with calculating the profits of their models and compare it to our model. Then they realize that what they learned at school is nothing compared to what there is to know.

Unfortunately, when the roots are pruned, the brain-like structures are cut off along with the sensitive tips. Ouch! After that, it is as if this interference makes the trees lose their sense of direction underground.

Trees don't rely exclusively on dispersal in the air, for if they did, some neighbors would not get wind of the danger. Dr. Suzanne Simard of the University of British Columbia in Vancouver has discovered that they also warn each other using chemical signals sent through the fungal networks around their root tips, which operate no matter what the weather. Surprisingly, news bulletins are sent via the roots not only by means of chemical compounds but also by means of electrical impulses that travel at the speed of a third of an inch per second. In comparison with our bodies, it is, admittedly, extremely slow. However there are species in the animal kingdom, such as jellyfish and worms, whose nervous systems conduct impulses at similar speed. Once the latest news has been broadcast, all oaks int he area promptly pump tannins through their veins.

When you measure water pressure in trees, you find it is highest shortly before the leaves open up in the spring. At this time of year, water shoots up the trunk with such force that if you place a stethoscope against the tree, you can actually hear it.

Willows produce the defensive compound salicylic acid, which works in much the same way. But not on us. Salicylic acid, is a precursor of aspirin, and tea made from willow bark can relieve headaches and bring down fevers. Such defense mechanisms, of course, take time.

Every tree, therefore, is valuable to the community and worth keeping around for as long as possible. And that is why even sick individuals are supported and nourished until they recover. Next time, perhaps it will be the other way round, and the supporting tree might be the one in need of assistance. When thick silver-gray beeches behave like this, they remind me of a herd of elephants. Like the herd, they, too, look after their own, and they help their sick and weak back up onto their feet. They are even reluctant to abandon their dead. Every tree is a member of this community, but there are different levels of membership. For example, most stumps rot away into humus and disappear within a couple of hundred years (which is not very long for a tree). Only a few individuals are kept alive over the centuries, like the mossy "stones" I've just described. What's the difference? Do tree societies have second-class citizens just like human societies? It seems they do, though the idea of "class" doesn't quite fit. It is rather the degree of connection-or maybe even affection-that decides how helpful a tree's colleagues will be. You can check this out for yourself simply by looking up into the forest canopy. The average tree grows its branches out until it encounters the branch tips of a neighboring tree of the same height. It doesn't grow any wider because the air and better light in this space are already taken. However, it heavily reinforces the branches it has extended, so you get the impression that there's quite a shoving match going on up there. But a pair of true friends is careful right from the outset not to grow overly thick branches in each other's direction. The trees don't want to take anything away from each other, and so they develop sturdy branches only at the outer edges of their crowns, that is to say, only in the direction of "non-friends." Such partners are often so tightly connected at the roots that sometimes they even die together.

The researchers looked at about 700,000 trees on every continent around the world. The surprising result: the older the tree, the more quickly it grows.

In Ordnung, ein Labyrinth zu knacken, ohne ein Gehirn zu haben, das ist schon eine Leistung.

Slow down, breathe deep, and look around. What can you hear? What do you see? How do you feel?

a tree can be only as strong as the forest that surrounds it.

There is a scientific observation that speaks to this: the blood pressure of forest visitors rises when they are under conifers, whereas it calms down and falls in stands of oaks.

Perhaps the saddest plants of all are those we have enslaved in our agricultural systems. They seem to have lost the ability to communicate, and, as Wohlle-ben says, are isolated by their silence. “Perhaps farmers can learn from the forests and breed a little more wildness back into their grain and potatoes,” he advocates, “so that they’ll be more talkative in the future.

Every tree, therefore, is valuable to the community and worth keeping around for as long as possible. And that is why even sick individuals are supported and nourished until they recover.

The wood wide web has been mapped, traced, monitored, and coaxed to reveal the beautiful structures and finely adapted languages of the forest network. We have learned that mother trees recognize and talk with their kin, shaping future generations. In addition, injured tress pass their legacies on to their neighbors, affecting gene regulation, defense chemistry, and resilience in the forest community. These discoveries have transformed our understanding of trees from competitive crusaders of the self to members of a connected, relating, communicating system. Ours is not the only lab making these discoveries-there is a burst of careful scientific research occurring worldwide that is uncovering all manner of ways that trees communicate with each other above and below ground.

The real question is whether we help ourselves only to what we need from the forest ecosystem, and—analogous to our treatment of animals—whether we spare the trees unnecessary suffering when we do this. T

The trees in a forest care for each other, sometimes even going so far as to nourish the stump of a felled tree for centuries after it was cut down by feeding it sugars and other nutrients, and so keeping it alive.

Occasionally, a tree is harvested with care and removed using horses. And so that old trees can fulfill their destinies, 5 to 10 percent of the area is completely protected. Lumber from forests with such species-appropriate tree management can be used with no qualms of conscience. Unfortunately, 95 percent of the current forest practice in Central Europe looks quite different, with the use of heavy machinery and plantation monocultures.

In the case of Switzerland, a whole country is concerned with the species-appropriate treatment of all things green. The constitution reads, in part, that "account [is] to be taken of the dignity of creation when handling animals, plants and other organisms." So it's probably not a good idea to decapitate flowers along the highway in Switzerland without good reason. Although this point of view has elicited a lot of head shaking in the international community, I, for one, welcome breaking down the moral barriers between animals and plants. When the capabilities of vegetative beings become known, and their emotional lives and needs are recognized, then the way we treat plants will gradually change, as well. Forests are not first and foremost lumber factories and warehouses for raw material, and only secondarily complex habitats for thousands of species, which is the way modern forestry currently treats them. Completely the opposite, in fact.

But nature is much more complex than a clock, isn’t it? In nature, not only does one cog connect with another; everything is also connected by a network so intricate that we will probably never grasp it in its entirety. And that is a good thing, because it means that plants and animals will always amaze us. It’s important for us to realize that even small interventions can have huge consequences, and we’d do better to keep our hands off everything in nature that we do not absolutely have to touch.

Why is the world full of color anyway? Sunlight is white, and when it is reflected, it is still white. And so we should be surrounded by a clinical looking, optically pure landscape. That this is not what we see is because every material absorbs light differently or converts it into other kinds of radiation. Only the wavelengths that remain are refracted and reach our eyes. Therefore, the color of organisms and objects is dictated by the color of the reflected light. And in the case of leaves on trees, this color is green. But why don't we see leaves as black? Why don't they absorb all light? Chlorophyll helps leaves process light. If trees processed light super-efficiently, there would be hardly any left over-and the forest would then look as dark during the day as it does at night. Chlorophyll, however, has one disadvantage. It has a so-called green gap, and because it cannot use this part of the color spectrum, it has to reflect it back unused. This weak spot means that we can see this photosynthetic leftover, and that's why almost all plants look deep green to us. What we are really seeing is waste light, the rejected part that trees cannot use. Beautiful for us; useless for the trees. Nature that we find pleasing because it reflects trash? Whether trees feel the same way about this I don't know, but one thing is for certain: hungry beeches and spruce are as happy to see blue sky as I am.

Wherever forest can develop in a species-appropriate manner, they offer particularly beneficial functions that are legally placed above lumber production in many forest laws. I am talking about respite and recovery. Current discussions between environmental groups and forest users, together with the first encouraging results-such as the forest in Konigsdorf-give hope that in the future forests will continue to live out their hidden lives, and our descendants will still have the opportunity to walk through the trees in wonder. This what this ecosystem achieves: the fullness of life with tens of thousands of species interwoven and interdependent. And just how important this interconnected global network of forests is to other areas of Nature is made clear by this little story from Japan. Katsuhiko Matsunaga, a marine chemist at the Hokkaido University, discovered that leaves falling into streams and rivers leach acids into the ocean that stimulate growth of plankton, the first and most important building block in the food chain. More fish because of the forest? The researcher encouraged the planting of more trees in coastal areas, which did, in fact, lead to higher yields for fisheries and oyster growers.

If a giraffe starts eating an African acacia, the tree releases a chemical into the air that signals that a threat is at hand. As the chemical drifts through the air and reaches other trees, they “smell” it and are warned of the danger. Even before the giraffe reaches them, they begin producing toxic chemicals. Insect pests are dealt with slightly differently. The saliva of leaf-eating insects can be “tasted” by the leaf being eaten. In response, the tree sends out a chemical signal that attracts predators that feed on that particular leaf-eating insect. Life in the slow lane is clearly not always dull. But

According to Massimo Maffei from the University of Turin, plants-and that includes trees-are perfectly capable of distinguishing their own roots from the roots of other species and even from the roots of related individuals. But why are trees such social beings? Why do they share food with their own species and sometimes even go so far as to nourish their competitors? The reasons are the same as for human communities: there are advantages to working together. A tree is not a forest. On its own, a tree cannot establish a consistent local climate. It is at the mercy of wind and weather. But together, many trees create an ecosystem that moderates extremes of heat and cold, stores a great deal of water, and generates a great deal of humidity. And in this protected environment, trees can live to be very old. To get to this point, the community must remain intact no matter what. If every tree were looking out only for itself, then quite a few of them would never reach old age. Regular fatalities would result in many large gaps in the tree canopy, which would make it easier for storms to get inside the forest and uproot more trees. The heat of summer would reach teh forest floor and dry it out. Every tree would suffer.

So, let's get back to why the roots are the most important part of a tree. Conceivably, this is where the tree equivalent of a brain is located. Brain? you ask. Isn't that a bit farfetched? Possibly, but now we know that trees can learn. This means they must store experiences somewhere, and therefore, there must be some kind of a storage mechanism inside the organism. Just where it is, no one knows, but the roots are the part of the tree best suited to the task. The old spruce in Sweden also shows that what grows underground is the most permanent part of the tree-and where else would it store important information over a long period of time? Moreover, current research shows that a tree's delicate root networks is full of surprises. It is now an accepted fact that the root network is in charge of all chemical activity in the tree. And there's nothing earth shattering about that. Many of our internal processes are also regulated by chemical messengers. Roots absorb substances and bring them into the tree. In the other direction, they deliver the products of photosynthesis to the tree's fungal partners and even route warning signals to neighboring trees. But a brain? For there to be something we would recognize as a brain, neurological processes must be involved, and for these, in addition to chemical messages, you need electrical impulses. And these are precisely what we can measure in the tree, and we've been able to do so since as far back as the nineteenth century. For some years now, a heated controversy has flared up among scientists. Can plants think? Are they intelligent?

Whether we can somehow listen in on tree talk is a subject that was recently addressed in the specialized literature. Korean scientists have been tracking older women as they walk through forests and urban areas. The result? When the women were walking in the forest, their blood pressure, their lung capacity, and the elasticity of their arteries improved, whereas an excursion into town showed none of these changes. It's possible that phytoncides have a beneficial effect on our immune systems as well as the trees' health, because they kill germs. Personally, however, I think the swirling cocktail of tree talk is the reason we enjoy being out in the forest so much. At least when we are out in undisturbed forests. Walkers who visit one of the ancient deciduous preserves in the forest I manage always report that their heart feels lighter and they feel right at home. If they walk instead through coniferous forests, which in Central Europe are mostly planted and are, therefore, more fragile, artificial places, they don't experience such feelings. Possibly it's because in ancient beech forests, fewer "alarm calls" go out, and therefore, most messages exchanged between trees are contented ones, and these messages reach our brains as well, via our noses. I am convinced that we intuitively register the forest's health.

In the symbiotic community of the forest, not only trees but also shrubs and grasses—and possibly all plant species—exchange information this way. However, when we step into farm fields, the vegetation becomes very quiet. Thanks to selective breeding, our cultivated plants have, for the most part, lost their ability to communicate above or below ground—you could say they are deaf and dumb—and therefore they are easy prey for insect pests.12 That is one reason why modern agriculture uses so many pesticides. Perhaps farmers can learn from the forests and breed a little more wildness back into their grain and potatoes so that they’ll be more talkative in the future. Communication

Y es que no hay que humanizar en absoluto a los animales, sino únicamente entenderlos mejor; porque estas comparaciones son sobre todo para entender que los animales no son criaturas estúpidas que se hayan quedado notablemente por debajo de nosotros desde un punto de vista evolutivo, y sólo hayan recibido apagadas versiones de nuestra rica paleta en lo relativo al dolor y demás.

In a forest that has been left to its own devices, the genetic makeup of each individual tree belonging to the same species is very different. This is in contrast to people, who are genetically very similar. In evolutionary terms, you could say we are all related. In contrast, the individual beeches growing in a stand near where I live are as far apart genetically as different species of animals.

I, for one, welcome breaking down the moral barriers between animals and plants. When the capabilities of vegetative beings become known, and their emotional lives and needs are recognized, then the way we treat plants will gradually change, as well. Forests are not first and foremost lumber factories and warehouses for raw material, and only secondarily complex habitats for thousands of species, which is the way modern forestry currently treats them. Completely the opposite, in fact.

Living cells must have food in the form of sugar, they must breathe, and they must grow, at least a little. But without leaves-and therefore without photosynthesis-that's impossible. No being on the planet can maintain a centuries-long fast, not even the remains of a tree, and certainly not a stump that has had to survive on its own. It was clear that something else was happening with this stump. It must be getting assistance from neighboring trees, specifically from their roots. Scientists investigating similar situations have discovered that assistance may either be delivered remotely by fungal networks around the root tips-which facilitate nutrient exchange between trees-or the roots themselves may be interconnected. In the case of the stump I had stumbled upon, I couldn't find out what was going on, because I didn't want to injure the old stump by digging around it, but one thing was clear: the surrounding beeches were pumping sugar to the stump to keep it alive.

We are not just protecting nature somewhere out there or giving things up simply to prevent the extinction of apparently unimportant beetles or species of birds. On the contrary, with every step we take to help conserve the ecosystem that is the Earth, we are at the same time protecting ourselves and our quality of life, simply because we are a fully functioning part of the whole. Environmental conservation is and must be—literally and in the best sense of the word—about just one thing: self-care.

A person breathes in nearly 2 pounds of oxygen a day, so that's the daily requirement for about ten thousand people. Every walk in the forest is like taking a shower in oxygen. But only during the day. Trees manufacture large amounts of carbohydrates not only to lay them down as wood but also to satisfy their hunger. Trees use carbohydrates as fuel, just as we do, and when they do, they convert sugar into energy and carbon dioxide. During the day, this doesn't affect the air much because after all the additions and subtractions, there is still that surplus oxygen I just mentioned. At night, however, the trees don't photosynthesize, and so they don't break down carbon dioxide. Quite the opposite, in fact. In the darkness, it's all about using carbohydrates, burning sugar in the cells' power-generating stations, and releasing carbon dioxide. But don't worry, you won't suffocate if you take a nighttime ramble! A steady movement of air through the forest ensures that all the gases are well mixed at all times, and so the drop in oxygen near the ground is not particularly noticeable.

Even in a forest, there are loners, would-be hermits who want little to do with others. Can such antisocial trees block alarm calls simply by not participating? Luckily, they can't. For usually there are fungi present that act as intermediaries to guarantee quick dissemination of news. These fungi operate like fiber-optic Internet cables. Their thin filaments penetrate the ground, weaving through it in almost unbelievable density. One teaspoon of forest soil contains many miles of these "hyphae." Over centuries, a single fungus can cover many square miles and network an entire forest. The fungal connections transmit signals from one tree to the next, helping the trees exchange news about insects, drought, and other dangers. Science has adopted a term first coined by the journal Nature for Dr. Simard's discovery of the "wood wide web" pervading our forests. What and how much information is exchanged are subjects we have only just begun to research. For instance, Simard discovered that different tree species are in contact with one another, even when they regard each other as competitors. And the fungi are pursuing their own agendas and appear to be very much in favor of conciliation and equitable distribution of information and resources.

Giant hogweed is considered extremely dangerous because its sap, in combination with ultraviolet light, can burn human skin. Every year, millions are spent digging up plants and destroying them, without any great success. However, hogweed can spread only because the original forested meadows along the banks of rivers and streams no longer exist. If these forests were to return, it would be so dark under the forest canopy that hogweed would disappear. The same goes for Himalayan balsam and Japanese knotweed, which also grow on the riverbanks in the absence of the forests. Trees could solve the problem if people trying to improve things would only allow them to take over.

Life as a forester became exciting once again. Every day in the forest was a day of discovery. This led me to unusual ways of managing the forest. When you know that trees experience pain and have memories and that tree parents live together with their children, then you can no longer just chop them down and disrupt their lives with large machines. Machines have been banned from the forest for a couple of decades now, and if a few individual trees need to be harvested from time to time, the work is done with care by foresters using horses instead. A healthier—perhaps you could even say happier—forest is considerably more productive, and that means it is also more profitable.

When the logs in the fireplace crackle merrily, the corpse of a beech or oak is going up in flames. The paper in the book you are holding in your hands right now is made from the shavings of spruce, and birches were expressly felled (that is to say, killed) for this purpose. Does that sound over the top? I don't think so. For if we keep in mind all we have learned in the previous chapters, parallels can definitely be drawn to pigs and pork. Not to put too fine a point on it, we use living things killed for our purposes. Does that make our behavior reprehensible? Not necessarily. After all, we are also part of Nature, and we are made in such a way that we can survive only with the help of organic substances from other species. We share this necessity with all other animals. The real question is whether we help ourselves only to what we need from the forest ecosystem, and-analogous to our treatment of animals-whether we spare the trees unnecessary suffering when we do this. That means it is okay to use wood as long as trees are allowed to live in a way that is appropriate to their species. And that means that they should be allowed to fulfill their social needs, to grow in a true forest environment on undisturbed ground, and to pass their knowledge on to the next generation. And at least some of them should be allowed to grow old with dignity and finally die a natural death.

Students at the instituted for Environmental Research at RWTH Aachen discovered something amazing about photosynthesis in undisturbed beech forests. Apparently, the trees synchronize their performance so that they are all equally successful. And that is not what one would expect. Each beech tree grows in a unique location, and conditions can vary greatly in just a few yards. The soil can be stony or loose. It can retain a great deal of water or almost no water. It can be full of nutrients or extremely barren. Accordingly, each tree experiences different growing conditions; therefore, each tree grows more quickly or more slowly and produces more or less sugar or wood, and thus you would expect every tree to be photosynthesizing at a different rate. And that's what makes the research results so astounding. The rate of photosynthesis is the same for all the trees. The trees, it seems, are equalizing differences between the strong and the weak. Whether they are thick or thin, all members of the same species are using light to produce the same amount of sugar per leaf. This equalization is taking place underground through the roots. There's obviously a lively exchange going on down there. Whoever has an abundance of sugar hands some over; whoever is running short gets help. Once again, fungi are involved. Their enormous networks act as gigantic redistribution mechanisms. It's a bit like the way social security systems operate to ensure individual members of society don't fall too far behind.

In conjunction with his colleagues, Frantisek Baluska from the Institute of Cellular and Molecular Botany at the University of Bonn is of the opinion that brain-like structures can be found at root tips. In addition to signaling pathways, there are also numerous systems and molecules similar to those found in animals. When a root feels its way forward in the ground, it is aware of stimuli. The researchers measured electrical signals that led to changes in behavior after they were processed in a "transition zone." If the root encounters toxic substances, impenetrable stones, or saturated soil, it analyzes the situation and transmits the necessary adjustments to the growing tip. The root tip changes direction as a result of this communication and steers the growing root around the critical areas. Right now, the majority of plant researchers are skeptical about whether such behavior points to a repository for intelligence, the faculty of memory, and emotions. Among other things, they get worked up about carrying over findings in similar situations with animals and, at the end of the day, about how this threatens to blur the boundary between plants and animals. And so what? What would be so awful about that? The distinction between plant and animal is, after all, arbitrary and depends on the way an organism feeds itself: the former photosynthesizes and the latter eats other living beings. Finally, the only other big difference is in the amount of time it takes to process information and translate it into action. Does that mean that beings that live life in the slow lane are automatically worth less than ones on the fast track? Sometimes I suspect we would pay more attention to trees and other vegetation if we could establish beyond a doubt just how similar they are in many ways to animals.

Of all the plants, trees have the largest surface area covered in leaves. For every square yard of forest, 27 square yards of leaves and needles blanket the crowns. Part of every rainfall is intercepted in the canopy and immediately evaporates again. In addition, each summer, trees use up to 8,500 cubic yards of water per square mile, which they release into the air through transpiration. This water vapor creates new clouds that travel farther inland to release their rain. As the cycle continues, water reaches even the most remote areas. This water pump works so well that the downpours in some large areas of the world, such as the Amazon basin, are almost as heavy thousands of miles inland as they are on the coast. There are a few requirements for the pump to work: from the ocean to the farthest corner, there must be forest. And, most importantly, the coastal forests are the foundations for this system. If they do not exist, the system falls apart. Scientists credit Anastassia Makarieva from Saint Petersburg in Russia for the discovery of these unbelievably important connections. They studied different forests around the world and everywhere the results were the same. It didn't matter if they were studying a rain forest or the Siberian taiga, it was always the trees that were transferring life-giving moisture into land-locked interiors. Researchers also discovered that the whole process breaks down if coastal forests are cleared. It's a bit like if you were using an electrical pump to distribute water and you pulled the intake pipe out of the pond. The fallout is already apparent in Brazil, where the Amazonian rain forest is steadily drying out. Central Europe is within the 400-mile zone and, therefore, close enough to the intake area. Thankfully, there are still forests here, even if they are greatly diminished.

A good upbringing is necessary for a long life, but sometimes the patience of the young trees is sorely tested. As I mentioned in chapter 5, "Tree Lottery," acorns and beechnuts fall at the feet of large "mother trees." Dr. Suzanne Simard, who helped discover maternal instincts in trees, describes mother trees as dominant trees widely linked to other trees in the forest through their fungal-root connections. These trees pass their legacy on to the next generation and exert their influence in the upbringing of the youngsters. "My" small beech trees, which have by now been waiting for at least eighty years, are standing under mother trees that are about two hundred years old -- the equivalent of forty-year-olds in human terms. The stunted trees can probably expect another two hundred years of twiddling their thumbs before it is finally their turn. The wait time is, however, made bearable. Their mothers are in contact with them through their root systems, and they pass along sugar and other nutrients. You might even say they are nursing their babies.

Young developing leaves on normal trees are often tinged red thanks to a kind of sun block in their delicate tissue. This is anthocyanin, which blocks ultraviolet rays to protect the little leaves. As the leaves grow, the anthocyanin is broken down with the help of an enzyme. A few beeches or maples deviate from the norm because they lack this enzyme. They cannot get rid of the red color, and they retain it even in their mature leaves. Therefore, their leaves strongly reflect red light and waste a considerable portion of the light’s energy. Of course, they still have the blue tones in the spectrum for photosynthesis, but they are not achieving the same levels of photosynthesis as their green-leaved relatives. These red trees keep appearing in Nature, but they never get established and always disappear again. Humans, however, love anything that is different, and so we seek out red varieties and propagate them. One man’s trash is another man’s treasure is one way to describe this behavior, which might stop if people knew more about the trees’ circumstances.

It all starts with the wolves. Wolves disappeared from Yellowstone, the world’s first national park, in the 1920s. When they left, the entire ecosystem changed. Elk herds in the park increased their numbers and began to make quite a meal of the aspens, willows, and cottonwoods that lined the streams. Vegetation declined and animals that depended on the trees left. The wolves were absent for seventy years. When they returned, the elks’ languorous browsing days were over. As the wolf packs kept the herds on the move, browsing diminished, and the trees sprang back. The roots of cottonwoods and willows once again stabilized stream banks and slowed the flow of water. This, in turn, created space for animals such as beavers to return. These industrious builders could now find the materials they needed to construct their lodges and raise their families. The animals that depended on the riparian meadows came back, as well. The wolves turned out to be better stewards of the land than people, creating conditions that allowed the trees to grow and exert their influence on the landscape. My

So trees communicate by means of olfactory, visual, and electrical signals. (The electrical signals travel via a from of nerve cell at the tips of the roots.) What about sounds? Let's get back to hearing and speech. When I said at the beginning of this chapter that trees are definitely silent, the latest scientific research casts doubt even on this statement. Along with colleagues from Bristol and Florence, Dr. Monica Gagliano from the University of Western Australia has, quite literally, had her ear to the ground. It's not practical to study trees in the laboratory; therefore, researchers substitute grain seedlings because they are easier to handle. They started listening, and it didn't take them long to discover that their measuring apparatus was registering roots crackling quietly at a frequency of 220 hertz. Crackling roots? That doesn't necessarily mean anything. After all, even dead wood crackles when it's burned in a stove. But the noised discovered in the laboratory caused the researchers to sit up and pay attention. For the roots of seedlings not directly involved in the experiment reacted. Whenever the seedlings' roots were exposed to a cracking at 220 hertz, they oriented their tips in that direction. That means the grasses were registering this frequency, so it makes sense to say they "heard" it.

Young spruce sprout particularly well in the dead bodies of their parents. This is known as “nurse-log reproduction” in English and, somewhat gruesomely, as Kadaververjüngung, or “cadaver rejuvenation,” in German. The

It's true that some of this carbon dioxide does indeed return to the atmosphere after a tree's death, but most of it remains locked in the ecosystem forever. The crumbling trunk is gradually gnawed and munched into smaller and smaller pieces and worked, by fractions of inches, more deeply into the soil. The reain takes care of whatever is left, as it flushes organic remnants down into the soil. The farther underground, the cooler it is. And as the temperature falls, life slows down, until it comes almost to a standstill. And so it is that carbon dioxide finds its final resting place in the form of humus, which continues to become more concentrated as it ages. In the far distant future, it might even become bituminous or anthracite coal.

When they are choosing their trees, deer go for whatever is unusual. Whether they choose spruce, beech, pine, or oak, they will always choose whatever is uncommon locally. Who knows? Perhaps the smell of the shredded bark acts like an exotic perfume. It's the same with people: it's the rare things that are most highly prized.

It's a shame you can't transport entire beeches or oaks into the laboratory to find out more about learning. But, at least as far as water is concerned, there is research in the field that reveals more than just behavioral changes: when trees are really thirsty, they begin to scream. If you're out in the forest, you won't be able to hear them, because this all takes place at ultrasonic levels. Scientists at the Swiss Federal Institute for Forest, Snow, and Landscape Research recorded the sounds, and this is how they explain them: Vibrations occur in the trunk when the flow of water from the roots to the leaves is interrupted. This is a purely mechanical event and it probably doesn't mean anything. And yet? We know how the sounds are produced, and if we were to look through a microscope to examine how humans produce sounds, what we would see wouldn't be that different: the passage of air down the windpipe causes our vocal cords to vibrate. When I think about the research results, in particular in conjunction with the crackling roots I mentioned earlier, it seems to me that these vibrations could indeed be much more than just vibrations-they could be cries of thirst. The trees might be screaming out a dire warning to their colleagues that water levels are running low.

Some species-like spruce-rely on timing. Male and female blossoms open a few days apart so that, most of the time, the latter will be dusted with the foreign pollen of other spruce. This is not an option for trees like bird cherries, which rely on insects. Bird cherries produce male and female sex organs int he same blossom, and they are one of the few species of true forest trees that allow themselves to be pollinated by bees. As the bees make their way through the whole crown, they cannot help but spread the tree's own pollen. But the bird cherry is alert and senses when the danger of inbreeding looms. When a pollen grain lands on a stigma, its genes are activated and it grows a delicate tube down to the ovary in search of an egg. As it is doing this, the tree tests the genetic makeup of the pollen and, if it matches its own, blocks the tube, which then dries up. Only foreign genes, that is to say, genes that promise future success, are allowed entry to form seeds and fruit. How does the bird cherry distinguish between "mine" and "yours"? We don't know exactly. What we do know is that the genes must be activated, and they must pass the tree's test. You could say, the tree can "feel" them. You might say that we, too, experience the physical act of love as more than just the secretions of neurotransmitters that activate our bodies' secrets, though what mating feels like for trees is something that will remain in the realm of speculation for a long time to come.

Even though scientists haven't fully researched the relationships yet, we do know that higher species diversity stabilizes the forest ecosystem. The more species there are around, the less chance there is that a single one will take over to the detriment of the others, because there's always a candidate on hand to counteract the menace.

Whether it's a wolf ripping apart a wild boar or a deer eating an oak seedling, in both cases there is pain and death.

If things become dire for the fungi and their trees despite all this support, then the fungi can take radical action, as in the case of the pine and its partner Laccaria bicolor, or the bicolored deceiver. When there is a lack of nitrogen, the latter releases a deadly toxin into the soil, which causes minute organisms such as springtails to die and release the nitrogen tied up in their bodes, forcing them to become fertilizer for both the trees and the fungi.

To enter into a partnership with one of the many thousands of kinds of fungi, a tree must be very open-literally-because the fungal threads grow into its soft root hairs. There's no research into whether this is painful or not, but as it is something the tree wants, I imagine it gives rise to positive feelings. However the tree feels, from then on, the two partners work together. The fungus not only penetrates and envelops the tree's roots, but also allows its web to roam through the surrounding forest floor. In so doing, it extends the reach of the tree's own roots as the web grows out toward other trees. Here, it connects with other trees' fungal partners and roots. And so a network is created, and now it's easy for the trees to exchange vital nutrients (see chapter 3, "Social Security") and even information-such as an impending insect attack. This connection makes fungi something like the forest Internet.

Planted forests, which is what most of the coniferous forests in Central Europe are, behave more like the street kids I describe in chapter 27. Because their roots are irreparably damaged when they are planted, they seem almost incapable of networking with one another. As a rule, trees in planted forests like these behave like loners and suffer from their isolation. Most of them never have the opportunity to grow old anyway. Depending on the species, these trees are considered ready to harvest when they are about a hundred years old.

This ability to produce different compounds is another feature that helps trees fend off attack for a while. When it comes to some species of insects, trees can accurately identify which bad guys they are up against. The saliva of each species is different, and trees can match the saliva to the insect. Indeed, the match can be so precise that trees can release pheromones that summon specific beneficial predators. The beneficial predators help trees by eagerly devouring the insects that are bothering them. For example, elms and pines call on small parasitic wasps that lay their eggs inside leaf-eating caterpillars. As the wasp larvae develop, they devour the larger caterpillars bit by bit from the inside out. Not a nice way to die. The result, however, is that the trees are saved from bothersome pests and can keep growing with no further damage. The fact trees can recognize saliva is, incidentally, evidence for yet another skill they must have. For if they can identify saliva, they must also have a sense of taste.

Communication between trees and insects doesn't have to be all about defense and illness. Thanks to your sense of smell, you've probably picked up on many feel-good messages exchanged between these distinctly different life-forms. I am referring to the pleasantly perfumed invitations sent out by tree blossoms. Blossoms do not release scent at random or to please us. Fruit trees, willows, and chestnuts use their olfactory missives to draw attention to themselves and invite passing bees to sate themselves. Sweet nectar, a sugar-rich liquid, is the reward the insects get in exchange for the incidental dusting they receive while they visit. The form and color of blossoms are signals, as well. They act somewhat like a billboard that stands out against the general green of the tree canopy and points the way to a snack.

Plants communicating by means of sound waves? That makes me curious to know more, because people also communicate using sound waves. Might this be a key to getting to know trees better?

And how do trees register that the warmer days are because of spring and not late summer? The appropriate reaction is triggered by a combination of day length and temperature. Rising temperatures mean it's spring. Falling temperatures mean it's fall. Trees are aware of that as well. And that's why species such as oaks or beeches, which are native to the Northern Hemisphere, adapt to reversed cycles in the Southern Hemisphere if they are exported to New Zealand and planted there. And what this proves as well, by the way, is that trees must have a memory. How else could they inwardly compare day lengths or count warm days?

A biologist from Leningrad, Boris Tokin, described them like this back in 1956: if you add a pinch of crushed spruce or pine needles to a drop of water that contains protozoa, in less than a second, the protozoa are dead. In the same paper, Tokin writes that the air in young pine forests is almost germfree, thanks to the phytoncides released by the needles. In essence, then, trees disinfect their surroundings.

Research revealed the spruce to be an absolutely unbelievable 9,550 years old. The individual shoots were younger, but these new growths from the past few centuries were not considered to be stand-alone trees but part of a larger whole. And, I think, quite rightly so. The roots is certainly a more decisive factor than what is growing above ground. After all, it is the root that looks after the survival of an organism. It is the root that has withstood severe changes in climatic conditions. And it is the root that has regrown trunks time and time again. It is in the roots that centuries of experience are stored, and it is this experience that has allowed the tree's survival to the present day.

Every day in summer, trees release about 29 tons of oxygen into the air per square mile of forest. A person breathes in nearly 2 pounds of oxygen a day, so that's the daily requirement for about ten thousand people. Every walk in the forest is like taking a shower in oxygen. But only during the day. Trees manufacture large amounts of carbohydrates not only to lay them down as wood but also to satisfy their hunger. Trees use carbohydrates as fuel, just as we do, and when they do, they convert sugar into energy and carbon dioxide. During the day, this doesn't affect the air much because after all the additions and subtractions, there is still that surplus oxygen I just mentioned. At night, however, the trees don't photosynthesize, and so they don't break down carbon dioxide. Quite the opposite, in fact. In the darkness, it's all about using carbohydrates, burning sugar in the cells' power-generating stations, and releasing carbon dioxide. But don't worry, you won't suffocate if you take a nighttime ramble! A steady movement of air through the forest ensures that all the gases are well mixed at all times, and so the drop in oxygen near the ground is not particularly noticeable.

A multitude of algae live in salt water. Thanks to them, large amounts of oxygen bubble out of the ocean year round. Algal activity in the oceans balances the oxygen deficit in Central European forests in the winter so well that we can breathe deeply even when we are standing under beeches and spruce covered in snow.

Chief Marilyn Slett, president of Coastal First Nations, is well aware of the forest's importance: "Our leaders understand our well being is connected to the well being of our land and waters...If we use our knowledge and our wisdom to look after [them], they will look after us into the future." The Kichiwa of Sarayaku, Ecuador, see their forest as "the most exalted expression of life itself.

And one final limitation is an organism’s own genetics: an organism that is too greedy and takes too much without giving anything in return destroys what it needs for life and dies out.

Every five years, a beech tree produces at least thirty thousand beechnuts (thanks to climate change, it now does this as often as every two or three years, but we’ll put that aside for the moment). It is sexually mature at about 80 to 150 years of age, depending on how much light it gets where it’s growing. Assuming it grows to be 400 years old, it can fruit at least sixty times and produce a total of about 1.8 million beechnuts. From these, exactly one will develop into a full-grown tree—

los bosques son superorganismos, es decir, una estructura similar a un hormiguero.

When the logs in the fireplace crackle merrily, the corpse of a beech or oak is going up in flames. The paper in the book you are holding in your hands right now is made from the shavings of spruce, and birches were expressly felled (that is to say, killed) for this purpose. Does that sound over the top? I don’t think so. For if we keep in mind all we have learned in the previous chapters, parallels can definitely be drawn to pigs and pork. Not to put too fine a point on it, we use living things killed for our purposes. Does that make our behavior reprehensible? Not necessarily