Peter Wohlleben is a forester who believes trees are more like people than we think.

He believes trees have memories, they have friends, they have enemies, and they talk to each other over what he calls, the 'Wood Wide Web.'

Wohlleben writes about all this in his book, The Hidden Life of Trees, and he is in Calgary this week for the annual Wordfest, running until Oct. 16.

Wohlleben sat down with the Calgary Eyeopener to discuss the book ahead of a sold out talk at the Simmons Building.

Peter Wohlleben

Forester and author Peter Wohlleben says there's a lot more to trees than meets the eye. (Dave Dormer/CBC)

You write about trees as if they have human qualities, what do you mean when you say they talk to each other?

They do it not by sound, like we do, they do it... by scent. When a trees is hurt by an insect, which bites it, you can measure a reaction. There are electrical signals running through the tissue like when we feel pain but the tree thinks of its neighbours and warns them by scent. That's not the only thing, they also communicate by their roots system. They are connected via the roots and they send chemical and electrical signals.

So they give each other warnings, are there emotions attached to that? Is there fear and pain in those messages?

There's pain. For example, when trees suffer from heavy drought and the wood cracks inside and that hurts, the tree will always remember that. Trees have memories and will change its water management for the following years. When a tree feels pain from a drought, it warns the other ones so they can reduce their water consumption in advance.

Hidden Life of Trees

In his book, The Hidden Life of Trees, author Peter Wohlleben says trees are more like people than we think. (Peter Wohlleben)

On the flip side, can a tree experience happiness or joy?

We don't know that, science is not that far at the moment. That's like learning English for me by hitting the feet of surrounding people and hearing what they are telling me. It would just be a few words, which are not so nice. That's where we are now.

You talk about them as social beings? Do you believe a tree is a social being?

An unmanaged forest is able to cool down more than three, perhaps 10 degrees difference to a managed forest because they sweat together. Because they sweat out water they can cool down the climate and therefore the trees support each other without any doubt. For example, they support by pumping a sugar solution to a weak neighbour so they stay alive so the forest will be complete.

There are other arborists and foresters I've talked to in the past who believe trees communicate with each other, but they don't really anthropomorphize them the way you are, doesn't that put you on a different spectrum amongst foresters you meet?

They think on the esoteric side, but the book is 100 per cent serious, scientific research. But scientists always write without emotion… therefore no-one wants to read it and we have so many wonderful discoveries.

Hidden Life of Trees

Trees support each other by pumping a sugar solution to weaker trees through their root systems, says author Peter Wohlleben. (Peter Wohlleben)

When did this epiphany happen for you?

It was once when I felt an old beech tree and afterward I felt sorry for it. I realized it was a mother tree and nowadays I know mother trees care for their children. They suckle them — that's not a technical term I know — but they are pumping a sugar solution to the little ones and supporting them and when you put out those old fellows, then you destroy families.

Is it ethical to cut trees down?

It is. For example, this morning, I had breakfast, therefore I need farmland, or someone who owns it. And once there stood a primeval forest and I'm happy there is now farmland because I'm hungry in the morning. I just think we have to get things in a proper balance.


With files from the Calgary Eyeopener