I love trees and forests. I’ve loved them since I was a girl, when I’d wander in the woods that backed up to our yard, build lean-tos, and feel some magical sense of wonder being around the trees. Even today, out on a walk, I’ll stop next to a tree, lean against it, touch it, and experience the bark. There’s a connection I’ve always felt, but never understood.
This Radiolab episode feeds right into those feelings and makes me suspect my feeling of connection is grounded in the trees themselves.
The episode introduces the idea that trees are not just single organisms doing their own individual thing, but part of interconnected forest networks, communicating not just with other trees—including other tree species—but also with underground fungi. It’s a network of exchanged resources, the trees depending on the fungi for minerals and the fungi depending on the trees for sugar.
The network appears to be way more involved than my simple sugar-for-minerals sentence suggests. It’s like a “fungal freeway system connecting one tree to the next and to the next.”
Some of the ideas were mind-boggling.
- That the fungi, which look like white threads, can contain up to 7 miles of thread-like tubes in a pinch of dirt.
- Fungi get minerals out of the soil by hunting, mining and fishing.
- Trees can store sugar in fungi “banks,” which can hold it during good times, and loan it back when times are tough.
- Trees facing threats will send underground signals to warn other trees of danger, allowing the other trees to produce chemicals to help them withstand the threat.
- In one study, a single tree was connected to 47 other trees around it, like an airline flight pattern.
It’s a short episode but one whose ideas delighted me. The idea of forests as connected systems, communicating with each other, is mind-expanding. How we might view that idea, is beautifully summed up by the two guests:
“The whole forest, there’s an intelligence there that’s beyond just the species…We don’t normally ascribe intelligence to plants, and plants are not thought to have brains, but when we look at the below-ground structure, it looks so much like a brain, physically, and now that we’re understanding how it works… there are so many parallels.”
Susanne Simard, Professor of Forest Ecology, University of British Columbia
“I do find it magical. I think there is something like a nervous system in the forest. Because it’s the same sort of large network of nodes, sending signals to one another. It’s almost as if the forest is acting as an organism itself. They talk about how honeybee colonies are sort of superorganisms, because each individual bee is sort of acting like it’s a cell in a larger body.
Once you understand the trees are all connected to each other, they’re all signaling each other, sending food and resources to each other, it has the feel, the flavor of something very similar.”
Jennifer Frazer, a science writer with Scientific American
This episode is as compelling today as it was when it was released in 2016. Especially if you have a special place in your heart for trees.
A fun, invigorating and thought-provoking listen.
- Podcast Link: Radiolab
- Episode Link: From Tree to Shining Tree
- Hosts: Jad Abumrad and Robert Krulwich
- Date: 7/30/16
- Duration: 32 minutes
- Pursuing Podcasts Rating: 5 out of 5
Radiolab “is a radio show and podcast weaving stories and science into sound and music-rich documentaries.”
Here are links to some more information on the subject of plant “intelligence:”
- Smarty Plants¸ February 13, 2018 Radiolab episode that includes Jennifer Frazer as a guest and “revisits the hot-button topic of plant intelligence.”
- Dying Trees Can Send Food to Neighbors of Different Species, Scientific American, The Artful Amoeba blog, Jennifer Frazer, 5/9/15.
- Wood Wide Web, a blog referenced in the Radiolab Tree episode.
- Podcast Notes.org: Key takeaway notes from the Tree episode.
- Are Plants Conscious? Stefano Mancuso, TEDx Talk, 3/4/15
- The Roots of Plant Intelligence, Stefano Mancuso, Stefano Mancuso, TED Talk, July 2010