Expert: Dana Krempels, Ph.D. - 12/20/2007

Question
I was wondering if you could identify this fungus, or point me in the right direction.  The fungus lived in the basement of an old farmhouse, which had a dirt floor, stone walls, and a wooden beamed cieling.  The fungus grew out from the cieling, and reached entirely from the cieling to the floor in places (Approx 6.5 feet) such as around the walls, and was at least two feet thick in the centre of the room, where it was thickest.  The bottom surface was irregular, with "stalactites," and when cut, the texture was almost identical to that of a white cafe mushroom that one would buy at the supermarket.  When it was exposed to light, the entire fungus shrivelled up and disappeared - there was nothing left to indicate that it had even been there, not so much as marks on the wood.

Answer
Dear Jessie,

I had to pass this question along to our faculty's mycologist, who is capable of identifying just about any fungus you can imagine.  He's Dr. David Janos, a world-renowned expert on mycorrhizal ("fungus root") symbiotic associations, and is amazing with all things fungal.  Here's what he wrote in response to the description you sent:

"I have no idea what is being described.  It is very hard for me to
believe that if the "fungus" was "at least two feet thick" that upon
exposure to "light" it would disappear totally without a trace.  If the
humidity in that basement was sufficient to support that much actual fungus
growth, then they would have had to fully open and air out the place for at
least a couple of weeks for the fungus to "disappear".  If there is any
truth or slight accuracy whatsoever to the description, I'd guess that it
was the mycelium of a serious wood-rotter like Fomes annosus, possibly
living in the beams of the ceiling.  I would not want to spend any time in
that basement, and absolutely would not want to walk on the floor of the
house above if there was enough rot in those beams to produce that much
mycelium!"

So unfortunately...no positive I.D.  If you do see it again, try to get a sample, take a picture, and either email it to me (so Dave can have a look) or send it to a local university who has a mycologist on the faculty.  In any case, it sounds as if it's a good thing that it's gone.

(Maybe a space alien?)  ;)

Have a great holiday!

Dana