People were aware of the fungus growing in Malheur National Forest in Oregon for quite some time, but it was investigated more closely by researchers when they realized that it was responsible for killing large groves of evergreen trees. When foresters cut into an infected tree they would find spreading white filaments, mycelia, which draw water and carbohydrates from the tree to feed the fungus. Researchers collected samples of the fungus from a widespread area and analyzed the DNA. A large sample of the specimens they collected turned out to be from a single organism. They estimate that it has been growing for about 2,400 years, covering 3.4 square miles. It’s name is Armillaria solidipes but it’s known as the “Humongous Fungus.”
You would not see a huge, looming mushroom in the forest where it grows. Armillaria grows and spreads primarily underground and the sheer bulk of this organism lies in the earth, out of sight. Occasionally, during the fall season, this specimen will send up golden-colored “honey mushrooms” that are the visible evidence of its hulking mass beneath. Scientists have not yet begun to attempt to estimate the weight of this specimen of Armillaria. Low competition for land and nutrients have allowed this organism to grow so huge; it possibly covers more geographical area than any other living organism.
I that’s pretty amazing.