The Hidden Life of Trees
What They Feel, How they Communicate: Discoveries from a Secret World
by Peter Wohlleben
Greystone Books, 2016 (Originally Ludwig Verlag, in Germany, 2015)
Regular readers of this blog will have noticed that my tastes run in a few particular directions—natural history, human history, biography, food—at the expense of a broader view. In my defense, I should note that during my day job I read an awful lot of business, self-help and personal improvement books—the books I describe here are pure recreation for my mind. Still, that does not excuse the fact that there is little if any poetry or fiction on my reading table.
Occasionally I feel I should read more of these genres. Then I come across a text like Peter Wohlleben’s and think, who needs fiction when reality is so extraordinary? Wohlleben’s charming, passionate text will put you in a mind of ents, say, or Tolkien or the Brothers Grimm. Evidently the idea of an enchanted forest isn’t so far-fetched after all.
Like many scientific popularizers (Bill Bryson, Malcolm Gladwell et al.), Wohlleben pulls together threads from existing research. With them he weaves an image of arboreal life that is not necessarily visionary but certainly revelatory for the lay reader. A professional forester in Germany, he makes a strong case that some sort of sentience exists within and among trees. Certainly, trees cooperate more than we imagined. One of his most charming stories describes his realization that some “stones” in his forest were in fact the living, nubby elbows of ancient tree roots associated with a large bole that had been felled centuries earlier. He puzzled over this, eventually concluding that the roots were being sustained by interconnections to the roots of other, still standing trees that were sharing resources. Why, he wonders, would they do such a thing? This question informs the book.
Trees help each other in other ways. Acacias, upon being browsed by giraffes, release ethylene to communicate to surrounding acacias, which quickly pump bitter chemicals into their own leaves, making them unpalatable to grazers. Giraffes thus will graze a tree for a few minutes (until its leaves turn bitter), then move a hundred meters, or turn upwind, in search of trees that haven’t yet got the news about giraffe mealtime.
Wohlleben describes tree etiquette and tree school. He delves into the continuing mysteries of how trees move water so far up their trunks (what we learned in middle school turns out to be wrong), and explores the ability of trees to communicate via electrical impulses through what appears to be a nervous system. He argues that trees feel pain, and makes a powerful case for how a forest is not simply the trees but the inestimably diverse, largely misunderstood microbiome in the soil that allows trees, and all things, to thrive. One cannot read this book without wincing at our ill-informed attempts to “manage” forests, especially the forest plantations quite common in Europe.
A growing body of work about the sentience of animals informs contemporary discussions about ethical scientific research, animal husbandry and human diet. Wohlleben would like us to have the same discussion regarding how we relate to trees. Although his perspective is refreshing to the point of feeling radical, it is not a new one. John Muir, arguing for the protection of California redwoods 125 years ago, lamented, “It is easy to murder trees. They cannot run away.” It is easy also to dismiss Muir and Wohlleben's argument that trees are sentient beings and deserve to be treated as such. But our view of the world must change as our understanding of the facts changes. John Muir was considered a crank in his time. Today he is an icon. So consider this: in 2015 the country of Ecuador amended its constitution to grant legal standing to nature. In that nation a river or a forest now has standing to sue for protection or relief from abuse. Is that the misguided result of cranks? Or is it a harbinger?