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how do trees communicate with each other
Do plants talk? Not in words, but a wounded plant can send a message through the air. The classic field experiments used sagebrush and wild tobacco.
A clipped sagebrush releases scent molecules, called volatile organic compounds, V-O-Cs. They drift away through the air toward a neighbor, here a wild tobacco plant.
The neighbor that catches the smell turns on its defenses early. In the field, those tobacco plants lost less to hungry insects.
To test that it travels by air, researchers put barriers between the plants. Blocking the air stopped the warning; blocking only the soil did not.
Now underground. Many tree roots partner with fungus, wrapping them or growing inside, and it trades soil minerals for sugar from the tree. Here are three neighbors.
Each root system spreads its own fine roots through the soil. The fungus lives on them, so the roots are where any link between trees must begin.
Fungal threads can touch the roots of more than one tree, so a web could join them. That is the wood wide web idea.
But a 2023 review found the big claims outrun the evidence. Whether the web carries sugar and warnings between trees is still debated.
So, in short: scent signals through air are well shown in experiments. The fungus story is still being tested, and the hype got ahead of the data.
Plants do send signals, and scent on the air is the best-shown route between neighbors, and the underground story is a good question that is still open.