Mushroom Networks Beneath Forests Transmit Chemical Signals Like a Brain

Walk through any healthy forest, and beneath your feet lies one of the most complex communication networks on Earth — a vast, branching web of fungal threads called the mycorrhizal network, often nicknamed the "Wood Wide Web."

Tree roots and fungi form symbiotic partnerships in which the fungi extend their thread-like hyphae across the forest floor. These connect the root systems of dozens or even hundreds of trees — sometimes across multiple species — into a shared underground exchange.

What Trees Send Through It

• Carbon and sugars: Mature "mother trees" send up to 30% of their carbon to younger seedlings, including those of different species
• Nitrogen and phosphorus: Redistributed where most needed
• Distress signals: Trees attacked by insects release chemical alarms that warn neighbors to ramp up defenses
• Water: During drought, deeper-rooted trees can share water with shallower-rooted neighbors

Implications

This research, pioneered by ecologist Suzanne Simard, has fundamentally changed our view of forests — from collections of competing individuals to communicating super-organisms. It has also informed modern forestry: clear-cutting destroys these networks, and replanted areas struggle to thrive without them.