How forests communicate underground
For centuries, scientists dismissed the idea that plants could communicate. Trees were seen as solitary beings—rooted in place, competing for light, passively reacting to their surroundings. But recent discoveries have rewritten the script. It turns out, plants do talk—not in words, but through scent, root signals, and even underground networks. This article explores the fascinating world of botanical communication: how trees warn their neighbours, share nutrients, and support their kin. Welcome to the Wood Wide Web—nature’s quiet, leafy whisper network.
Outline
- Introduction
- Do Plants Really Communicate?
- The Wood Wide Web: Trees and Fungi
- Scent Signals and Airborne Messages
- Root Talk: Chemicals and Electromagnetic Pulses
- Trees That Mother Other Trees
- Competition vs Cooperation: Rethinking the Forest
- How Human Activity Disrupts the Conversation
- Final Thoughts
Introduction
The idea that plants are intelligent or communicative might sound like something out of a sci-fi film. But over the last few decades, researchers have uncovered undeniable proof: trees and plants send signals, both to each other and to other organisms in their ecosystem.
And no, they’re not just reacting to touch or sunlight—they respond, adapt, warn, and even help. It’s not quite speech, but it’s a complex language all the same.
Do Plants Really Communicate?
Yes—just not with vocal cords.
Plants “speak” using:
- Chemical signals
- Root exudates
- Electrical impulses
- Fungal networks
- Scent molecules
These signals allow plants to:
- Warn each other about predators
- Call in insect allies
- Share water and nutrients
- Recognise relatives
- Respond to stress long before it’s visible
It’s communication without consciousness as we understand it—but it works.
The Wood Wide Web: Trees and Fungi
Perhaps the most mind-blowing discovery in plant science is the underground mycorrhizal network—nicknamed the Wood Wide Web.
What is it?
A symbiotic relationship between tree roots and fungi. The fungi connect with roots and extend through the soil, creating an underground network that allows nutrients, water, and even messages to be transferred between plants.
How it works:
- Trees supply fungi with sugars (from photosynthesis)
- Fungi help trees access water, phosphorus, and nitrogen
- Through this web, trees send distress signals, share resources, and even help saplings survive
Dr Suzanne Simard, a Canadian forest ecologist, was one of the first to prove this network functions much like a neural network—trees are, quite literally, connected.
Scent Signals and Airborne Messages
When a plant is under attack—say, by aphids—it can release volatile organic compounds (VOCs) into the air that nearby plants detect and respond to.
Examples:
- Acacia trees in Africa emit ethylene gas when grazed, causing nearby trees to ramp up their tannin production (a bitter chemical that deters herbivores).
- Tomato plants exposed to VOCs from damaged neighbours will activate defence genes, even if they’re untouched.
- Willows, poplars, and maples have also shown this airborne alarm system.
It’s like a forest-wide “group text”: “Hey—trouble’s coming. Arm yourselves.”
Root Talk: Chemicals and Electromagnetic Pulses
Roots are more than anchors—they’re messengers.
Plants release exudates (sugars, acids, proteins) into the soil that:
- Attract beneficial microbes
- Warn other roots about toxins or pathogens
- Influence which nearby seeds germinate
Some studies suggest roots may also use electrical signalling—spikes in voltage similar to neural impulses—though this research is still emerging.
Imagine that: the ground beneath your feet alive with silent conversations.
Trees That Mother Other Trees
It gets even more emotional (yes, really). Studies show that older “mother trees” not only support the forest—they actively nurture their young.
They:
- Recognise their own offspring
- Channel more nutrients to related saplings
- Warn kin of drought or insect stress
- Continue to support the network even as they die
This isn’t Disney-level anthropomorphism. It’s documented science.
Suzanne Simard’s research on Douglas firs revealed that mother trees can increase the survival rate of their young by up to 400% when allowed to stay connected.
Competition vs Cooperation: Rethinking the Forest
For a long time, ecology focused on competition—the survival of the fittest. But the more we study plant networks, the clearer it becomes: cooperation is just as vital.
Trees don’t just battle for light—they:
- Share information
- Nourish each other
- Slow their own growth to avoid shading neighbours
- Form alliances with fungi and bacteria
This shifts how we see nature—not as a battlefield, but as a community.
How Human Activity Disrupts the Conversation
Deforestation and modern forestry practices often break these communication lines.
Clear-cutting forests:
- Destroys mother trees
- Disrupts fungal networks
- Isolates young trees without guidance or support
Monocultures (planting a single tree species) weaken forest resilience because:
- There’s less biodiversity
- Fungal networks are less complex
- Communication is reduced
If trees speak, then we need to stop cutting off their voices.
Final Thoughts
Plants don’t have brains or mouths—but they do communicate. They listen, respond, support, and survive through a complex system of signals and relationships.
Whether it’s warning their neighbours, feeding their young, or collaborating underground, trees and plants show us that intelligence can look very different from our own.
So next time you walk through the woods, remember: you’re not alone. You’re among beings quietly chatting through roots and air, leaves and spores—living their own rich, interconnected lives.
The forest speaks. The question is—are we ready to listen?
