The Armillaria fungus, commonly referred to as the honey mushroom, holds the distinction of being the world's largest mushroom.

It thrives in the Mulhall National Forest, nestled within the scenic Blue Mountains of eastern Oregon, USA.

Its colossal proportions are nothing short of astonishing; the honey mushroom stretches to such immense dimensions that its discovery is nothing short of awe-inspiring. It boasts an incredible radius of 5.6 kilometers, a size comparable to an entire hill.

In 1998, Dr. Katherine Parks, a distinguished female scientist hailing from the Pacific Northwest Research Center of the United States Department of Agriculture and Forestry, embarked on an investigation into the mysterious demise of cedar trees within the National Forest Park.

Dr. Parks discerned striking discrepancies between the ailing trees and the deceased ones. Vast swathes of resplendent golden mushrooms had taken root. This revelation ignited Dr. Catherine's curiosity, sparking the question: Could these mushrooms be linked to the trees' demise?

To unravel this enigma, Dr. Katherine Parks meticulously extracted root samples from over a hundred trees that had perished in diverse locations. The results of the subsequent DNA tests took Dr. Catherine by surprise.

Fungi were unearthed in every root sample, but the most staggering revelation lay in the comparisons.

Astonishingly, over 60 of the samples belonged to a single bacterial strain! It is crucial to note that these samples were sourced from distinct areas, signifying the presence of an unprecedented, gargantuan fungus beneath more than 60 deceased trees.

Dr. Parks employed aerial photography to pinpoint locations where tree mortality was prevalent and systematically sampled the roots of the affected trees.

The fungus was conclusively identified through DNA testing, and after comparing 112 samples, the world's largest fungus, the "honey mushroom," was positively identified.

The Armillaria fungus, often dubbed the "honey mushroom," emerges from minuscule, invisible spores and boasts a history that spans over 2,400 years. Regrettably, its growth is often accompanied by the demise of trees.

Wherever this fungus takes root, a plethora of dead trees can be found in its wake.

According to expert assessments, this colossal "honey mushroom" extends over an impressive 3.5 miles (equivalent to 5.6 kilometers) into the earth, delving a substantial 3 feet (approximately 0.9 meters) into the soil and encompassing an area akin to 1,665 football fields.

The mushroom's weight remains a mystery, as it defies estimation. Profoundly, the scientific community acknowledges that no animal or plant of larger dimensions has been discovered through current scientific means.

This isn't the first encounter with an Armillaria fungus of such magnitude, as an expansive specimen covering 1,500 acres was discovered in Adams, Washington, in 1992.

Forest scientists in the United States are eager to develop methods for controlling the fungus due to its severe tree-damaging tendencies. Nonetheless, there is also an intriguing belief among scientists that this formidable fungus may have unforeseen positive contributions to offer in the future.

During the research conducted on the honey mushroom, it was observed that the hyphae of this fungus form attachments to tree roots, absorbing water and carbohydrates from the tree, consequently leading to the tree's demise.

The hyphae can penetrate the ground to depths of up to 10 feet, invading tree roots through a combination of pressure and biochemical enzymes. It's worth noting that the arid climate of eastern Oregon may well contribute to the mushroom's impressive size.