His voice floated over the smell of paint thinner and dusty signs, while I peered at the bored carpenter's hands. I felt the surface of the biscuit's rings while he methodically impressioned the other slice.
"Seven. Eight. Nine. Ten." He dimpled the rings with his pen, demarcating decades, units of life. My fingers still brushed lightly over the rings. The thin ones passed quickly like sliding over frigid ice of harsh winters, while the thick ones were rough with the definition of dank humidity and warm summer rain. He began tallying the hemlock's decads now. A human life passed by, a century, the Civil War, the birth of a nation. There were thirty in all. I mumbled something about the French and Indian War, while imagining the thin tree rising through a young forest inhabited only by Chippewa and animals yet unacustomed to the easy picking of a park garbage can.
We left the old breakroom and the remains of the three-hundred year old tree and perched on the skeleton struts of dismantled picnic tables, talking about the oldest and largest living thing.
"I thought the largest living thing was the aspen stand they found out West," he let the ash fall from his cigerette.
"Well, I'm not sure, this was quite a few years ago, I think," I said gingerly, unsure of my facts. I spoke of the humungous fungus, which, at least I had heard, was the largest living organism discovered. I recalled that it stretched across great distances of Michigan's Upper Peninsula. "Over in the west end," I added.
Later, I filled in my flagging memory with news reports which dripped with the mysterious aura of this giant fungus. I realized it was important in the Guinness Book of World Records sense, but surely there was something more to this than a number one spot on the list of stupendously big things. I found that there was something more though, something that would raise questions about how living things grow and the entire definition of an "individual."
The humongous fungus is a collection of fungi contained entirely within the genus Armillaria, commonly known as honey mushroom. While the mushrooms of the different honey mushroom species are definitely average-sized (and pretty tasty, so they say), the vastness of the Armillaria exists under the soil. The members of Armillaria form long rhizomorphic pipelines between distant food sources. Thus, the honey mushroom grows through vegetative means and seems to fullfill many of the strictures of the "individual" classification (apart from genetic evidence this includes the fact that a single region of the fungus cooperates with the others). The unveiling of this notable property among fungus and plants (like quaking aspen) spurred a decade of quantitative one-upmanship and a cascade of "biggest organism" newspaper stories.
It all began very simply with a grant study by the Department of Defense, which sought to discover the ecological effects of the not-so-super-secret ELF communication system scattered around the Upper Peninsula and Wisconsin. Around one of the control stations, the researchers noticed some odd floral behavior. The harvest of local oak trees had left behind fields of stumps which were being replanted with the more-profitable red pine saplings. Some of the saplings were being ravaged by the honey mushroom, while the former population of oak trees had been left in relative peace.
The size of one of the clones of this particular species of honey mushroom Armillaria gallica was a fairly accidental discovery and one unrelated to the initial goals of the study. Myron Smith, one of the primary researchers, explains in an e-mail to Thomas "Fungus of the Month" Volk:
I have often been asked something like,'what made you look for a large fungus?' Like most discoveries (and this is a point that needs to be stressed to granting agencies), we did not set out to make this discovery. Initially, (at least when Jim and I came on the scene) we wanted to find out how mitochondrial DNA was inherited in fungi in nature (Smith, Duchesne, Bruhn and Anderson, 1990). The first year we went out and sampled from a 120 x 60 m area. Nearly every sample was identical for mDNA and mating type. The second year we extended our sampling over a 1 km transect through the area and, again, detected this one wide-spread genotype. By extending the areas sampled in subsequent years, we were finally able to delimit the large area occupied by this genotype and then go on to show that this genotype likely represents an 'individual'.
He was working for the Department of Defense
after all. Through many hours of painstaking testing and research, Smith and his colleagues determined that one indivdual honey mushroom clone occupied an area of thirty-seven acres and weighed about 100 tons. Using growth measurements they also judged the age of the fungus to be at least 1,500 years.
Around this time the study was published in the April 1992 edition of Nature with a title that included the words "among the world's largest and oldest things." This was dramatic enough to attract the attention of mainstream media. Suddenly, the quant and lonely UP was on the global stage,
as major national newspapers and television newtorks rained phone calls down on the office of researcher Johann Bruhn at Michigan Technological University. What Thomas Volk terms "the fungus wars" had begun.
Hardly a couple months later, stories of a single Armillaria ostoyae fungus spread over 1,500 acres in Washington state surfaced. Questions also arose, though, about the rigourousness of the research and the validity of this new claim. Finally, eight years later, Armillaria gallica's domineering reign of "largest fungus" unequivocally faded into the twilight, when a 2,200 acre Armillaria ostoyae giant in Eastern Oregon was tested with the same scientific rigor as that first, noble fungus.
Now the world has moved onto bigger and older things, but the memory of that first discovery lives on in the Upper Peninsula and elsewhere. The gallica fungus graces the side of U-Haul trucks in their series of SuperGraphics and the inhabitants of Crystal Falls, Michigan honor it with the annual Fungus Fest. The festivities include a youth golf tournament, a humongous flea market, a duck race, and a humongous ten-foot-square pizza. Say what you like about the population of Crystal Falls, but never say they disrespect their fungus.
The last bits of the carpenter's cigerette smoldered in his fingers and he let it fall into the tangled metal under him. He looked toward me and simply said "Well," then moved resolutely toward the breakroom. It was our break from break and life moved along seemingly unchanged. The fungus was still out there though, under the surface growing larger, growing older and changing things at its own pace.
Works Cited / Referenced:
1. Most of this information originated from Thomas Volk's incredibly detailed page: http://botit.botany.wisc.edu/toms_fungi/apr2002.html. "The Humongous Fungus--Ten Years Later."
2. Details of Crystall Falls fascinating yearly fest can be found at: http://www.crystalfalls.org.
3. U-Haul keeps information on all SuperGraphics they use at: http://www.uhaul.com/supergraphics.
4. Refresher on Michigan history provided by: http://www.baylisslib.org/chipearlyhist.html and http://freedom.up.net/~wpbjo/second.htm.