We are not the only creatures with intelligence or the capacity for love. The Hidden Life of Trees reminds me of My Octopus Teacher because it expands how we human beings look at other beings who share the world. The fungi form webs of mycelium which help trees communicate and filter out bad stuff like heavy metals. Fungi, I now know, contain substances found in no other plants, which makes fungi unique beings on the Earth. Various fungi seem to explode out of the ground, and it’s miraculous to watch as the shapes and colors appear. I’m always stunned by extreme time-lapse shots of things growing - leaves popping out of branches in the spring and slowly unfurling. In German forests, wild boar, for instance, eat up all the acorns, but the trees cahoot with each other not to drop acorns every year so that the boar won’t rely on acorns for reliable sustenance.

Oak trees collude about when to drop their acorns. A healthy tree with enough water, defends itself against the beetle by emitting chemicals that repel the animal. Trees feel pain and react to parasites like the spruce bark beetle. The roots put out all this growth and the tree stays alive.

Its trunk is much younger, and it’s surround by shrubbery, which is part of the tree. Old Tjikko is more than 9,500 years old, but Wohlleben’s lesson about the tree is that its root system is what’s kept the organism going all these years. Wohlleben is German, but the film travels with him to Canada’s Vancouver Island, where he talks to native people about their connection to the forest, and to Sweden where he shows students the oldest tree in the world. The film shows him in a forest talking to Korean students, in a classroom lecturing on aspects of tree life, or recording thoughts and pictures of trees on his phone. The movie centers on German writer and forester Peter Wohlleben, who in 2015 published his famous book, The Hidden Life of Trees. The Hidden Life of Trees is chock full of mind-blowing information about trees, but as good documentaries should do, this one takes you well beyond its surface. I never knew that a forest of spruce trees might be one organism, that trees might talk to each other, that the mushrooms growing under trees might be part of a community with those trees or that if you want a good, healthy diverse forest after an old one has been clear cut for timber, don’t replant, just leave it alone. For most of Peter Wohlleben’s The Hidden Life of Trees, I sat with my jaw dropped and thought “Who knew?”

The hidden life of the trees