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The charismatic forester argues that trees can be a powerful weapon in the fight against climate change – so long as we leave them alone

Elon Musk has offered a prize of $100m for the best carbon capture and sequestration proposal. I can save his committee a lot of time. The money should go to Peter Wohlleben, the German forester whose book The Hidden Life of Trees was the most improbable and encouraging blockbuster of 2015. Wohlleben’s idea is this: leave forests alone. Stop fiddling with them, thinking that we can deal with climate change better than nature. If we fiddle, our Romes will burn.

The Hidden Life argued that trees are social and sensate. The Power of Trees shows that they can be our saviours. But it’s terribly hard to let ourselves be saved. We think we can be the authors of our salvation. We are doers by constitution. Of course, there are things we could and should be doing, but in terms of forestry practice, often what’s billed as part of the solution is part of the problem.

Anyone who has planted a tree in their garden knows that it has a profound effect – it makes your garden cooler in summer and warmer in winter. Forests do that on a grand scale. A deciduous forest in summer is often as cool as a lake. Berlin is 15C warmer than the ancient forests nearby. The coniferous monocultures so beloved of commercial foresters are not such good coolers: they’re up to 8C warmer than their deciduous counterparts.

Forests cool by transpiring. If there’s no water, there’s no cooling. Drought can kill trees fast, but trees have many sophisticated ways of dealing with it, and Wohlleben sets them out. As a species, we have survived many climatic changes by changing our behaviour – and that’s how trees survive, too.

Crucially, trees learn from their past traumas and produce offspring programmed with those lessons. Trees that have narrowly escaped drought are more prudent in the future: they slow their growth and ration their drinking. They have two main methods for influencing their children: the first is good parenting. Mother trees regulate their children’s growth by changing the rate at which they drip-feed them with sugar solution through root networks, and children growing in the rain and light shadow of the mother won’t drink heavily or overeat. The second is epigenetic inheritance, which enables useful behavioural traits to be passed on fast to future generations.

Deciduous forests in particular remove greenhouse gases effectively, and sequester carbon for as long as they live. The rate of carbon capture increases until they’re around 450 years old. Cut them down and burn them and you’re releasing carbon dioxide not just from the wood, but also from the forest floor – as the soil, previously cool in the shade, warms and therefore accelerates the metabolism of microorganisms, which consume the remaining humus.

The way of the woods is not the way of the market, and if we see forests as warehouses we are doomed. Foresters must be more than stockholders, shelf stackers, shippers and restockers. We need a radically new ethos. Deciduous trees are not “harvest-ready” at 200 years: they are teenagers. Tree planting isn’t necessarily good: the collateral costs may be extortionate. We must interrogate comforting expressions such as “renewable energy”, and learn the real cost of our toilet paper.

If we don’t learn to leave the trees alone, the trees will eventually be alone anyway – but without us. Wohlleben brilliantly and readably shows us how urgent and how hard it is to do nothing.

Charles Foster’s next book, Cry of the Wild, is published in May by Doubleday. The Power of Trees by Peter Wohlleben, translated by Jane Billinghurst, is published by Greystone (£18.99). To support the Guardian and Observer order your copy at guardianbookshop.com. Delivery charges may apply.

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