I live in San Francisco where winters are cool and damp rather than
cold. For the off-season, I had my supers stored in an area where they
were protected from rain but otherwise exposed to dampness. This was a
very damp winter, too. As a result, the supers developed a bad case of
mold. It is especially bad in comb that had been used to raise brood,
where many of the cells are full of mold. Even the wooden frames of my
honey supers have mold growing on them.
 
Could the mold in the brood comb be harmful to the bees, and, in the
case of mold on the frames of my honey supers, could it be harmful to
the honey?