Mold in the humidor?

Mold is one of the most pernicious substances on earth. Even if you are successful at treating the wood with alcohol, sanding away the top layer, and hermetically sealing the grain, some spores will probably remain. There are also mold spores in the air and in every cigar we have. While your efforts will probably help in reducing their number, the only real protection against mold is environmental vigilance. Don't let the humi get warm and moist enough to let them grow again.