What the World’s Largest Organism Reveals About Fires and Forests

This story was originally published on Atlas Obscura.

There is something massive and prehistoric under the Blue Mountains of Oregon. Pando, Utah's famous grove of quaking aspens is almost invisible to the untrained eye because it is the largest recorded organisms on Earth. A single specimen of honey mushroom, or Armillaria ostoyae, has been growing for thousands of years.

It covers nearly 4 square miles within the Malheur National Forest and is estimated to weigh as much as 35,000 tons. The conditions created by the 20th century forest management are believed to have contributed to the record-setting dimensions of the fungus. It continues to grow, expanding mostly underground in networks of mycelia. Beneath the bark of the trees, the fungus moves up into them. It eats away at the tree, killing it, and then eating the dead wood for decades. The Humongous Fungus is a symbol of an ailing, at-risk forest, the consequences of fire suppression, and the challenge of restoring the health of the environment.

If there were no trees dying, I wouldn't have a job, says forest pathologist Mike McWilliams, who calls himself the unofficial tour guide of the massive fungus.

A country store under towering pines on US Highway 26 advertises its famous buffalo burgers and ice cream. He leads the way along one Forest Service gravel road. The party has to get out to hike.

The dense forest gives way to a balding hillside. The work of the Humongous Fungus is not being done by the trees here, but by a smaller relative. There are several Armillaria specimen in Malheur, but it is hard to tell with boots on the ground. Researchers collect samples and map them.

The trees become smaller and closer together as McWilliams drives deeper into the forest. Foresters call the ground surface fuel because of the fallen trees and brush. The main attraction of the tour is the Humongous Fungus.

The decay that Malheur's most famous resident leaves behind is easier to see. A collection of toppled trees is what should be a thick and thriving forest. The 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846 888-666-1846

It got so big because of the history of fire suppression.