There's a Fungus Among Us

EhobaX writes "BBC News reports, 'Swiss scientists have found what they say may be Europe's biggest mushroom - covering an area about the size of 35 football pitches.'"

Comments

I think some Quaking Aspen are bigger.

[JQuick]

Some aspen forests are dominated by clones. Additional trunks sprout from the roots of its sibling, break the surface, and appear to be a distinct individuals even though the root system is still partially shared among them.

If the shared root structure is broken, certain clumps of trees may now be considered separate organisms, despite being genetically identical siblings. Logically, even a few capillary sized connections would suffice to define their status as a single organism.

The mycelia underground by which this fungus spreads, and which serves to define these large mushrooms as a single organism are analogous to the shared root system of these quaking aspen forests. The fruiting bodies (mushrooms) on the surface grow from a shared network of underground fibers. The trees and mushrooms are each genetically homogeneous, interconnected biological systems, thus single organisms.

One such tree/clone-forest in Utah named Pando (latin for "I spread") has over 47,000 trunks, weighs over 7 million kilograms, and covers about 118 acres. A large number of similar clone forests exist in Canada. Though some believe one or more of these Aspen groves in Canada is larger, Pando is older by several hundred years.

So, this mushroom in Washington has a web of mycelia that span 2200 acres. On the surface it seasonally fruits above ground bodies in shady areas scattered across this area. That's big. Despite the fact that the horizontal surface spanned by the underground network is about 20 times larger, perhaps the Aspen edges it out.

Above ground the volume and mass of the aspen, per acre, is significantly greater. One trunk, its branches, roots, and leaves, are certainly more massive than a significant number of mushrooms. At nearly 5 thousand trunks per acre, that's a lot of wood! Since the acreage difference is only a factor of 20, one only need show that one acre of Aspen is 20 times heavier or voluminous than one acre of this mushroom. I found no data to confirm this but I believe that 1 acre of Pando would kick one acre of mushrooms butt.

I'll grant that the mushroom covers a larger footprint on the soil thus has a larger area (measure in acreage). The mycelia also may edge out the root system per acre in displaced soil volume. Considered in their entirety I'd be very surprised if by volume or mass it is truly the largest. Thus, I find it hard to believe that this mushroom is a larger organism than Pando.

BTW, These clone forests are quite interesting in the fall and spring. The connected clones change color in the fall, and open their leaf buds in the spring in parallel. It is possible to see the boundary of clone forests, and spot genetically different isolated trees within the boundary of the forest. Mid season they are visually indistinguishable. At those times, isolated trees, or boundaries between genetically diverse stands of trees, are easy to spot visually.