A few years ago a beekeeper friend announced to me that mold had taken over her hives and killed all her bees. Now whenever I see mold—or even hear about it—I think about her. When I tried to explain that it was the other way around, that the bees died and then the mold came, she didn’t believe a word of it. She cut out all the combs and washed the frames with bleach. Too bad.
A variety of molds will grow on the combs when the moisture in the hive gets too high. The moisture gets too high when there are not enough bees to fan it away. I suppose the confusion arises because these moldy combs frequently contain dead bees that are also covered with mold, so it looks like the mold killed everything.
According to various sources, one of the molds frequently found on combs is Penicillium waksmanii which can actually inhibit the growth of certain bacteria, including American foulbrood. Other molds are usually present as well, as evidenced by the different colors—usually blue, white, yellow, or gray.
If you have a dead hive loaded with mold you will be tempted to discard the comb, but it is usually not necessary. The first thing you need to do is decide how the colony died or became weak. If you can eliminate American foulbrood and colony collapse disorder, then you can re-use the combs.
The first thing to do is take the frames to a warmish, dry place where they can dry out for a few days. These things can smell wicked—like moldy stuff does—so put them in a place where they won’t bother you. Separate any frames that are molded together and let them air dry. As they dry the mold growth will slow down and then stop.
Once the combs are dry you can store them in an empty super. After your colonies build up in the spring you can place the moldy super on top of a big, vigorous colony and the bees will clean and polish every cell in a matter of a few days. Worker bees always clean old cells prior to re-use anyway, so this is not an unnecessary burden on the bees. The bees are very thorough and, after they are done, the combs can be used for brood or honey production. It’s amazing, but no taste or smell of mold will remain on the combs.
Rusty
Interesting clarification on what came first, the mold or the dead bees. Re: reusing old bee equipment. I take it by your post you’d say “Forget it” if it was foulbrood or CCD?
Nancy,
Right. We know American foulbrood can be transmitted on old comb and should be burned. Even though we don’t know what causes CCD, reused equipment appears to infect bees who move into it. In either case it is not worth the risk. Plain old mold, however, is not a problem.
Good to know. I lost one of my hives last summer & it smelled fermented & was abundantly moldy, but I don’t think it was AFB. I was looking at replacing it but maybe I will try airing it out. Thanks!
Thank you so much. This is exactly the problem I was having today and I wanted to let you know that I appreciated your work.
Exactly what I was looking for. As a new beekeeper, I thought the best thing to do with the drawn out supers that the bees cleaned last fall were all dry and double bagged them and put them in the basement – they would be fine – WRONG! lol
The 6 drawn out supers that we have are going on the porch today to start their drying process…..we are going to get some rain so we’ll be sure to bring them in – hopefully the stink will be gone by then!
It’s amazing how much moisture is in frames and combs. They look and feel dry, but once you seal them up they mold in no time. I think most of us have done this at one time or another, so don’t worry. But the moldy smell won’t go away until the bees have cleaned them up.