Trees do communicate. Who knew? Suzanne Simard did. And she told us about it ever so passionately and eloquently in my favourite talk of the TED Summit. (In my informal poll of other attendees, she was tied with Jennifer Brea for favourite overall).
Simard discovered that trees are connected underground by an enormous fungal network, the mycelium*. Her first experiment showed that trees can pass carbon to other trees through this underground network, within a single species and across species such as birch and fir; and she has also shown the transfer of water and other nutrients such as nitrogen. The transfer is bidirectional and varies according to the other tree's need - trees got more when they were heavily shaded in the summer, for instance.
All trees seem to have this capacity to connect, but some trees have more connections than others. These hub, or mother, trees can be connected to hundreds of other trees. Simard calls these mother trees because they favour sending nutrients to their own secondary seedlings. Trees can even send warning signals in distress situations, wisdom that can protect the future of a forest. So the network goes beyond a symbiotic transport network to being a neural network that actually transmits intelligence. The forest is more than the sum of its trees; it's a complex organism in its own right. This amazing information brings a new sense of wonder to a walk in the woods. You almost wonder if you’ll feel the vibration of this extraordinary social network beneath your feet.
Simard's research has implications for the forestry industry. Harvesting forests should respect the powerful function of these hub trees because they hold the future of the forest in their roots.
By the way, Simard is Canadian. As Canada Day draws to a close, how appropriate to post this blog celebrating a Canadian who blew everyone away at TED. Simard was authentic, passionate, articulate without being artificial, and totally charming. She left us with a new lens to appreciate forests.
*Mushrooms are just the tip of the iceberg of this vast underground network (See a short summary of one of my favourite talks from a previous TED about mushrooms and mycelium. This was also the favourite of that conference. What is it about mushrooms?) What's underground is gigantic compared to what we see on the surface.