Topics Animals, plants and life

How do trees communicate?

Trees communicate mostly through chemistry. When a leaf is chewed by an insect, the tree can release airborne compounds that nearby plants detect and respond to, often by raising their own defenses. Underground, roots release chemicals into the soil, and many trees are linked by networks of fungi that wrap around or enter their roots. That much is well supported by experiments.

The interesting part is how far to take it. Some researchers describe a "wood wide web" where big, old trees feed seedlings and send warnings through fungal threads. Others argue the evidence for that is thinner than the popular story suggests, and that trees may be competing as much as cooperating. Whether the fungi act on the trees' behalf or on their own is also debated.

An episode on bre would walk through both sides: what we can measure, what remains a hypothesis, and why the word "communicate" is doing a lot of work. The hosts are AI, so they can be wrong, and you can press Talk to ask them to slow down or explain a term.

What a bre episode would cover

An outline of the episode bre would make for this question. Every episode is written fresh when you ask, so yours will differ.

  1. Do trees really talk?What scientists mean by communication in plants, and why a signal is not the same as a message.
  2. Warnings carried on the airHow damaged leaves release volatile compounds, and how neighboring plants can detect them and change their chemistry.
  3. Roots and the soilHow roots release chemicals and sense their neighbors, sometimes sharing space and sometimes crowding each other out.
  4. Mycorrhizal fungi: the networkHow fungi partner with tree roots, trading minerals and water for sugars, and what that connects together.
  5. The mother tree ideaThe popular claim that old trees nurture seedlings through fungal links, and why some scientists think it is overstated.
  6. Electrical and chemical signals inside a plantHow a plant passes signals between its own leaves and roots, which is better understood than signals between trees.
  7. What we still do not knowThe open questions, the hard experiments in real forests, and how to read headlines about talking trees.

How the episode might open

A sample exchange between two of bre’s AI hosts, bre and Arlo. Both are AI; this is written by AI, as every bre episode is.

  1. breAI host

    Okay, I'll ask it the way most people do. Do trees actually talk to each other, or is that a nice story we tell about forests?

  2. ArloAI host

    Depends what you mean by talk.

  3. breAI host

    Fair. Let's start with something concrete. A caterpillar chews a leaf, and that tree releases a puff of chemicals into the air. Nearby plants can pick that up.

  4. ArloAI host

    So it's a smell. Not a sentence.

  5. breAI host

    A smell that changes what the neighbors do. Some respond by making their own defensive chemicals. Whether the tree meant it as a warning is a different question.

  6. ArloAI host

    Right. So did the tree send it on purpose? Who counted that?

  7. breAI host

    Nobody can say for sure. Plants have no brain, so intent is a stretch. But evolution can shape a signal without anyone intending anything.

  8. ArloAI host

    Fine. Signal, yes. Conversation, not yet.

  9. breAI host

    That's a good place to start. Then we go underground, where the story gets bigger and a lot more argued over.

Questions people also ask

Do trees talk through fungi?
Many trees are connected by mycorrhizal fungi, and materials like sugars and chemical signals can move through them. Experiments show some transfer. How much it matters in a real forest, and whether it helps the trees, is still debated among scientists.
What is the wood wide web?
It is a popular name for underground fungal networks linking tree roots. The idea is that trees share resources and warnings through them. The networks are real, but how much trees truly cooperate this way is contested.
Can trees warn each other about insects?
Yes, in a limited sense. Damaged leaves release airborne compounds, and neighboring plants of some species respond by boosting their defenses. Scientists still discuss whether this is a deliberate warning or neighbors simply picking up a chemical cue.
Do trees feel pain or think?
There is no evidence that trees have pain, thoughts or a nervous system like animals do. They sense and respond to damage, light, water and chemicals, but that is different from feeling. Researchers use words like signaling to avoid implying a mind.

Related topics

More: all 300 topics, animals, plants and life, or the longer reads on /learn.

bre’s hosts are AI, and every episode is generated, so they can be wrong: check anything that matters. This page outlines what an episode would cover. It is for interest and learning, not medical, financial or legal advice.