Armillaria ostoyae

In Oregon's Blue Mountains lies something extraordinary, a single organism stretching across nearly four square miles.

It isn't a whale or a giant tree, but a fungus, Armillaria ostoya, also known as the honey fungus.

Underground, its filaments thread through the soil, connecting to the roots of countless trees.

By some estimates, this one individual weighs hundreds of tons and maybe thousands of years old.

At first glance, it looks like an ordinary forest, pine trees, streams, and meadows.

But hidden beneath the soil lies the largest living organism known on Earth, a single fungal network of Armillaria ostoyae, often called the honey fungus.

This colossal mycelium stretches for nearly four square miles and is thought to be thousands of years old.

Every mushroom you see popping up from the ground, there is just one tiny piece of this enormous creature.

Now, if you're ready, let's begin.

The world's largest living organism is a forest fungus.

Hidden beneath the soil of Oregon's Blue Mountains lies something almost impossible to imagine.

It looks like an ordinary forest floor at first glance, scattered with trees and fallen leaves.

But beneath it all stretches the threads of a single fungus, weaving through the earth like a living web.

This organism, Armillaria ostoyae, covers an area of nearly four square miles and is believed to be thousands of years old.

Though its mushrooms sprout briefly above ground, the real body of the fungus is an underground lattice of microscopic filaments called mycelium.

Scientists consider it the largest living organism on Earth, far bigger than any whale, tree, or coral reef.

In some cases, it spreads across thousands of acres, forming one of the largest organisms on Earth.

In Oregon's Blue Mountains, a single honey fungus, Armillaria solidipes, covers over two thousand acres and is estimated to be thousands of years old This vast organism grows slowly, spreading through the forest floor, its hyphae branching and reconnecting in endless patterns.

From above, you would never know it exists.

You might see scattered mushrooms, small golden clusters appearing each autumn, but beneath your feet lies a living network larger than many cities.

It is a fungus.

In the Blue Mountains of Oregon, scientists discovered a honey fungus, Armillaria ostoyae, that covers more than two thousand acres.

It has been growing for thousands of years, perhaps as long as eight thousand years, spreading slowly through the soil, decomposing wood, and connecting the entire forest.

Most fungal networks are not quite this large, but even a modest network can be astonishing.