In the old growth forests of coastal British
Columbia there is a fungus which has been used
medicinally for 2000 years. It is a bracket fungus called agarikon or quinine
fungus (Laricifomes officinalis, Fomitopsis officinalis). Bracket fungi are the
shelf shaped wood decay ones that grow on trees and logs. Most of them are
perennial and continue to grow for many years. They make a new layer of spore
producing tubes on the underside of the bracket each year. If a bracket fungus
is cut in half, you can see the annual layers analogous to the annual rings in
a tree trunk.
The agarikon is one of these bracket fungi, but a rare and
unusual one. It grows high up in the canopy of very large, old trees, and the
brackets can live for many decades. If it is on the trunk it is hoof shaped
like many other shelf fungi. On a branch, however, it tends to grow vertically
downwards, like a thick white icicle. If you see one, which is unlikely, it is
usually well beyond reach. To actually get your hands on it, you need to find a
big fallen tree. The generic name refers to Larix, the larch tree, for in Europe it
grows on old larch trees. In BC its host is Douglas fir. Like all such fungi,
what we see is the fruiting body, essentially a spore producing flower. The
growing parts of the organism are felts and hyphal threads which grow through the
tree year after year, as it is a parasite on these old trees.
The fruiting body is a chunky white structure and the annual
layers are quite apparent even without sectioning it. Unlike other shelf fungi
it is soft and chalky on the surface, and is very bitter. Identifying fungi by
taste is a common practice among mushroom lovers, but a warning is in order. If
you taste an unknown fungus do not swallow any of it. There are many toxic
fungal compounds.
Agarikon (Laricifomes officinalis)
In all the years of studying fungi, I had never seen the
agarikon in nature. Except for two specimens I retrieved from mushroom shows,
of unknown origin, it remained very elusive. That was until last year, on a
Nature Vancouver hike through an old forest near Hope. A centuries old Douglas
fir had recently fallen beside the trail, and attached to it was an agarikon!
Its chalky white surface was unmistakable.
What is so special about this fungus? Its rarity is, of
course, one of the significant features. It only grows on old trees, and even
in old growth forests it is uncommon. As old growth forests are now uncommon,
the agarikon is even more uncommon than it once was. Although it has been known
in Europe since at least Roman times, it is
almost extinct there now. Very few old growth stands remain in Europe .
There are reports that it now survives only on larches in the Slovenian Alps.
Strengthening the case for protecting agarikon and its old
forests, is research on the medicinal potential of this fungus, and the
importance of maintaining as much of its genetic diversity as possible. This
research has uncovered both antibacterial and antiviral activity. Agarikon has
been used traditionally to treat both tuberculosis and smallpox, and First
Nations probably also used it as a medicine. Figures carved from agarikons were
sometimes placed on the graves of shamans.
The potential of this fungus is yet another reason for
preserving our old growth forests. The loss of agarikon could very well result
in the loss of effective treatments for serious diseases. There are also other
fungi restricted to old growth stands, and the medicinal properties of fungi
have been poorly researched. With the rapid advances in molecular biology and
biochemistry that are now taking place, the promise of agarikon and other
forest dwellers may yet be realized, provided we protect the habitats where
they dwell.
