Mystery #4Tier 3plants and fungi

How do threads of hidden fungi team up with plant roots deep underground?

Under the soil, wrapped around the roots of almost every plant, lie fine pale threads of fungus, from the same kingdom as mushrooms and mould. They are not attacking the plant. Somehow the fungus and the roots are working together as a team. What could a plant and a fungus possibly do for each other down there in the dark?

A red and white fly agaric mushroom in grass, the visible tip of a fungus whose threads are teamed up with tree roots below — Photo: Andrew Smith · CC BY-SA 2.0 · via Wikimedia Commons

Your guess

What do you think? How might hidden fungus threads and plant roots help each other underground?

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