Translated by Jane Billinghurst, author and forester Peter Wohlleben's latest book The Heartbeat of Trees: Embracing Our Ancient Bond with Forests and Nature, with the aid of the latest scientific research, shows how deeply humans are connected to the natural world. The book also explores the language of the forest, the consciousness of plants, and the eroding boundary between flora and fauna.
In the excerpt below, from Chapter 9. In Close Contact with Trees, is an exploration of the possible ways humans and trees might communicate.
The excerpt here has been reproduced here with kind permission from the publisher, Penguin Random House India.
Why can't we communicate with trees the same way we communicate with, say, elephants? I like to compare the two because they have much in common. Both live in social groups and look after not only their young but also their elders. That famous elephant memory is also found in trees, and both communicate in languages that we didn't even recognize at first. Trees communicate through their interconnected root systems, and elephants communicate using sounds below the range at which we can hear, which they pick up through their feet over distances of many miles. Both engender in us a feeling of admiration and a desire to interact with them. We get a feeling of well-being when we run our fingers over the rough skin of both creatures, and what we would love above all is to get a reaction from them.
And here there is a distinct difference between elephants and trees. The animal lets us know what it likes. It responds by reaching out its trunk and making contact. There is definitely non-verbal communication going on here. And that is exactly what many nature lovers wish could happen with trees. But the little voice in my head, firmly grounded in the conservative views of science, immediately shouts: "No. That is taking things too far." And yet, I am a very inquisitive person, and when I consider everything that has been discovered in the field of natural sciences " take quantum physics, for example " then I'd like to take a closer look before I reject an idea as being impossible. And what has been discovered about trees sometimes leaves the little voice in my head lost for words.
Can people communicate with trees? In order to answer this question, we first have to take a closer look at what we mean by "communicate." It is not enough that we consciously or subconsciously eavesdrop, so to speak, on the scents trees use to communicate among themselves. We have a physical reaction when we breathe them in, but for communication to happen, the trees also need to react to our signals. In the past, I have categorically refused to admit that this might be possible.
I am given to neither religious nor mystical thinking. Perhaps this is a result of being unable to escape the obligatory trip to church every Sunday when I was a child. The preacher and the monotonous, unvarying rituals of the service bored me. I invented novel games to pass the time, such as pressing my eyes tightly shut while I gazed up at the overhead lights until kaleidoscopic patterns of light appeared on my eyelids " not exactly what my parents were hoping I would get out of this weekly visit. In high school, I greedily soaked up anything to do with science, as it seemed the only logical way to understand the world. And that's how it has been for me ever since, even though I know that in many cases scientific facts are simply the current best explanation we have for natural processes. These explanations are often revised and many statements are qualified. That's how science operates.
I would like very much to believe in higher powers. I think it would be emotionally rewarding and surely comforting. But I can't, and therefore I bring a healthy portion of skepticism to the table when non scientists report experiences that sound unbelievable. I know that sounds strange coming from someone who writes about the feelings of trees and even talks about tree language, but these are both subjects on which even conservative scientists agree.
Let's take a moment to consider tree communication using the methods of modern science. Trees transpire chemical compounds. We are subconsciously aware of these compounds and we respond with changes in blood pressure. The tree, for its part, is unaware of our response " after all, we are not in contact with the tree in any way. And even if we hug the tree and talk of electric fields, which is one way we could mutually affect each other (because plants, like us, function partially by transmitting electric signals), there is still one huge obstacle: time. Trees, as we all know, are awfully slow. You can multiply the time it takes you to make contact with the tree by ten thousand to find out when you can expect a response.
If electrical impulses within the tree travel at a maximum speed of less than half an inch (1 centimeter) per second, and you make contact with the bark as you hug the tree, you could indeed get an answer right away. At least you could if the signal is processed at the point of contact, but that is something we do not know. Certain processes are regulated in the roots " how much water the leaves can use, for example " and the distance from the canopy to the roots and back to the canopy (or to your hands) varies from tree to tree, but it is a long way. And now we are approaching one of the central questions about what it is to be a tree. Trees store memories, respond to attacks, and transfer sugar solution, and perhaps even memories, to their offspring. All these abilities suggest that they must also have a brain. But no one has yet found any such thing.
Many parts of a living tree, like most parts of its trunk, are not even active anymore. With the exception of the outermost growth ring, none of the interior is still in use. You could even say it was dead. Nothing happens here apart from a few purely physical reactions, which are the same as the reactions you see in wood after a tree has been cut down. There's the swelling and shrinking caused by getting wet or drying out, for example, as well as resistance to fungal decay thanks to tannins the tree stored earlier in its life that now act as a sort of waterproofing.
The vessels that transport water are found on the outermost growth rings. And that's why it's especially damp, even wet, there, which has the added advantage that most fungi can't grow in these rings. Fungi like damp conditions, but (with a few exceptions) if they get too wet, they drown. And because many species of fungi like to make life difficult for trees, it's a good idea for the tree to have a zone running around the outer part of its trunk that repels most attackers.
But, let's get back to the brain. Even in the outer parts of the trunk, most of the cells are dead wood. And so, we can confidently discard any speculation that important information is being processed here.