Moldy Covers

[The15thMember]

I have alluded to this issue before, but I'm now at the point where I've tried a bunch of different things and nothing is working consistently, so I thought I'd toss it to the crowd for ideas. 

I constantly have trouble with mold of various species growing in between my inner and outer covers.  I seem to have less mold problems with migratory covers, since there is no space the bees don't have easy access to, but it happens occasionally with them too.  The mold is usually white or green, occasionally black, but only if I let the situation progress too far without a cleaning.  I have tried more ventilation and I've tried minimal ventilation.  Obviously I clean the tops with vinegar, or if it's really bad, I bleach the cover and repaint it, but it just comes right back after a month or two.  Is there anything else I can be doing to deter mold growth? 

[Occam]

I can't really speak to having mold growing on my covers but mold is tricky. The roots are next to impossible to get rid of even if you get rid of what you can see. That's why they don't recommend picking mold of bread and eating the "clean" bread, the roots are so present (I admit to having done this on occasion). It's the same with wood, once the roots get into it it can be impossible to eliminate. Have you tried replacing the covers altogether?

[The15thMember]

I can't really speak to having mold growing on my covers but mold is tricky. The roots are next to impossible to get rid of even if you get rid of what you can see. That's why they don't recommend picking mold of bread and eating the "clean" bread, the roots are so present (I admit to having done this on occasion). It's the same with wood, once the roots get into it it can be impossible to eliminate. Have you tried replacing the covers altogether?

No, because it happens to my new covers when I add hives.  I just got a poly hive, first time I've ever used it was when I put a swarm in it last month.  The lid and inner cover are brand new, well painted.  The second time I went to inspect them, mold under the cover.  Which is particularly discouraging, because this is one thing I was looking for improvement in with the poly hive. 

[Kathyp]

Living in Oregon mold is the state plant.  I gave up on it long ago, but I wonder if you painted the covers with that latex bathroom paint that is supposed to be mold resistant?

Otherwise, even though it looks icky, I have not found that it does any harm.  If they get bad enough, I scrub them and put them out in the sun in summer, but in winter there's not much to be done about it here.

[The15thMember]

Living in Oregon mold is the state plant.  I gave up on it long ago, but I wonder if you painted the covers with that latex bathroom paint that is supposed to be mold resistant?

Otherwise, even though it looks icky, I have not found that it does any harm.  If they get bad enough, I scrub them and put them out in the sun in summer, but in winter there's not much to be done about it here.

It's good to know you haven't noticed any problems with it.  Yeah, we're in a similar boat with humidity in my area, which, like the PNW, is a temperate rainforest. 

[Occam]

It may not be a bad thing either,  it contributes to the microbiome of the hive which may help good for the bees things want to be there

[salvo]

Hi Folks,

Many, many of my club's newbees as well as oldbees have this problem. just within the past few days several people have posted the issue. Many of them are using hive-top feeders and have inadequate ventilation.

sample:
First inspection and the girls were so docile. Spotted the queen! Lots of comb built out, some capped.
My inner cover and telescoping lid had blue mildew. Is this due to all the rain? Any reason to be concerned?
I searched the group and some said mold doesn?t affect bees but asking because mildew and mold are different.

I use a hive top feeder and had problems with moisture and mold last year. It was suggested by a mentor to increase ventilation by putting wooden tongue depressors or popsicle sticks on inner cover edges which worked great. Just that tiny bit of extra ventilation made a big difference.

I was that fill in mentor. I know I was her mentor's mentor.

Anyway, get a couple of paint stirrer sticks. Cut them in half, about five inches each. Put these pieces cross-ways, like a bracket across the corner. This lifts the outer cover about the thickness of two nickels.

The "dirty stuff" will stay there for a looong time, but it will be drier. If you want, you can staple screen ober the hole in the inner cover to keep possible robbers out. I tell newbees to always put an inner cover over their hive-top feeder. They can leave it in place when lifting the feeder for inspections, and, it's not totally open to the bees in the air when you're replacing the syrup. Slip it to one side.

Sal

[The15thMember]

It may not be a bad thing either,  it contributes to the microbiome of the hive which may help good for the bees things want to be there

I guess it's possible.  There are lots of different molds, and bees' respiratory systems are very different from ours. 

Hi Folks,

Many, many of my club's newbees as well as oldbees have this problem. just within the past few days several people have posted the issue. Many of them are using hive-top feeders and have inadequate ventilation.

sample:
First inspection and the girls were so docile. Spotted the queen! Lots of comb built out, some capped.
My inner cover and telescoping lid had blue mildew. Is this due to all the rain? Any reason to be concerned?
I searched the group and some said mold doesn?t affect bees but asking because mildew and mold are different.

I use a hive top feeder and had problems with moisture and mold last year. It was suggested by a mentor to increase ventilation by putting wooden tongue depressors or popsicle sticks on inner cover edges which worked great. Just that tiny bit of extra ventilation made a big difference.

I was that fill in mentor. I know I was her mentor's mentor.

Anyway, get a couple of paint stirrer sticks. Cut them in half, about five inches each. Put these pieces cross-ways, like a bracket across the corner. This lifts the outer cover about the thickness of two nickels.

The "dirty stuff" will stay there for a looong time, but it will be drier. If you want, you can staple screen ober the hole in the inner cover to keep possible robbers out. I tell newbees to always put an inner cover over their hive-top feeder. They can leave it in place when lifting the feeder for inspections, and, it's not totally open to the bees in the air when you're replacing the syrup. Slip it to one side.

Sal

Hm, as I'm thinking about this, perhaps when I had more ventilation, the mold didn't die (which is what I was hoping), but maybe it didn't continue to grow, or grow as quickly.  I have a couple moldy covers right now.  Maybe I'll do a little experiment and put a screened inner cover on some and leave some alone and see whether they grow at different rates.     

[Occam]

Keep us updated if you do, I'm curious to know what happens

[animal]

Don't know if this is bee-safe, but ...
The best "off the shelf" water based, mold resistant paint I've found is Zinsser Perma-whte exterior (about $40/gal.) It has a short shelf life (settles out bad and gets "clumpy")They also make an interior version, which I rarely buy. Pretreatment/cleaning with bleach(sodium hypochlorite based, highest concentration you can find, usually under 8%) If 7.5% : mix NO stronger than 1 part bleach to 4 parts water. I normally find 5 parts water to be best but I'm usually dealing with really bad mold.. and spraying a whole house. Lower than 1:5 concentrations work almost as well if you don't mind re-wetting several times and taking longer for it to work. Higher concentrations don't to work any better and make things more unpleasant for you.
For really stubborn spots, sealing with "Cover Stain" oil-based after cleaning. It's like "Kilz Original", but rated for exterior use as well.
A "real" paint store may have a mildewcide additive. If you use it, its best to use up the paint because it will shorten the shelf-life a remarkable amount.  Pretty sure all of the insecticide additives were taken off the market years back, but read the label closely anyway.(a real shame btw ... excellent product, small amount of insecticide placed exactly where you need it, and no spiders or dirt daubers on your soffets, but stupid people misused it so govt. gets involved.
They might also stock a mildew treatment that works a little differently than clorox and sometimes it will work a little better on some molds.
Killing mold in small areas you don't want to paint ... phenol, that old-time hospital smell, sure to bring back memories if you're over 50 and had childhood trauma in the hospital... but it can get expensive really quick and it's considered hazardous, so be careful.

One that might be of interest here is a borate treatment but it's either a real pain or expensive (if you buy stuff ready mixed). I use it where there's unfinished wood that has a history of dry rot and mold (usually basements, crawlspaces and sometimes attics. ... a mix of ethylene glycol antifreeze, borax and boric acid. You have to use the "concentrated" antifreeze, formerly called antifreeze, not the 50/50 or "ready to use" ... if it's not really thick and green, it's the wrong stuff.
Then you have to heat it (I do it over a fish cooker 5 gal. at a time) to dissolve the solids, cool down slowly, and you end up with a supersaturated solution that you can cut with water to spray or brush ... You can store it in the original jugs for a week or two if you put it in a temperature-stable place 
For beehive treatment, I would think surface cleaning (or painting) after soaking it into the wood, would be best. It will discourage/"kill a few" termites but will not affect carpenter bees fwiw.

[BeeMaster2]

Reagan,
Dealing with mold safely around bees is done in 2 parts. First you kill the mold with 10% chlorine bleach. The. You cover the same area with vinegar. The vinegar kills the spores. Both are safe for the bees.
Jim Altmiller

[The15thMember]

A "real" paint store may have a mildewcide additive.

I happen to have a great real paint store in my town, which has extremely knowledgeable and helpful people.  I should try talking to them about a better paint than the random outdoor mistints they give me at really discounted prices. 

Reagan,
Dealing with mold safely around bees is done in 2 parts. First you kill the mold with 10% chlorine bleach. The. You cover the same area with vinegar. The vinegar kills the spores. Both are safe for the bees.
Jim Altmiller

I don't know that I've ever tried both bleach and vinegar in a single cleaning.  I'll try that next time. 

[BeeMaster2]

Just bee sure not to use them together at the same time.
Jim Altmiller

[Oldbeavo]

Everyone is trying to solve the mould problem, but what is causing it.
I haven't seem mould in dry situations, why is there moisture?
Ventilation is something that us humans think is important, but i think it is not as important for the bees. They will sort it out.
Are we mucking up the bee system by doing what we think is necessary?
We have been using migratory lids with no vents, and have just gone around and stuffed toilet paper in the vents of older lids.

[The15thMember]

Just bee sure not to use them together at the same time.
Jim Altmiller

Right, right, obviously.  I didn't mean it like that. 

Everyone is trying to solve the mould problem, but what is causing it.
I haven't seem mould in dry situations, why is there moisture?
Ventilation is something that us humans think is important, but i think it is not as important for the bees. They will sort it out.
Are we mucking up the bee system by doing what we think is necessary?
We have been using migratory lids with no vents, and have just gone around and stuffed toilet paper in the vents of older lids.

There is moisture because of my climate.  It is not at all uncommon for us to have relative humidity in the 90% range in the summer, and it rains a lot here.  There is mold in the forest, there is mold in the house, there is mold in the beehives.    I do have screened bottom boards for most of my hives, but neither my telescoping tops or migratory covers themselves have ventilation.  As I mentioned, I do own screened inner covers, but don't always use them, and I seem to have mold regardless. I do have a couple of solid bottom boards at the moment.  I'll have to see of those hives have less mold than the ones with screened bottoms.   

[Bob Wilson]

I never see mold, but then I almost always use top entrances, like Michael Bush suggests.
Georgia is very bad about high humidity, especially in summer, as I imagine most of the southeastern states are.

[Oldbeavo]

15th, i will be interested to see how the solid bottoms go. there was a Canadian study that basically said the human ventilation upsets the natural bee movement of air.
They said that bees move air horizontally across the frames and any thing that causes vertical air flow upset what the bees are trying to achieve.
We do have 3" vents across the bottom of the hive but i am starting to doubt if the bees need them, or i just think they do.

[animal]

Something I've run into in the last couple of years... and reminded of today ...
New plywood that molds almost immediately after getting damp. t's almost like one of those pre-seeded wildflower mats that my wife likes .. just get it wet and boom! stuff starts growing. I'm convinced that the plywood comes from the factory contaminated with spores.
The absolute worst offender seems to be the interior luaun stuff. .. moved a few scrap pieces that were dumped in the garage 3 days ago ... that  had been hit by just a few raindrops, not wet all over, leaned against wall ... moved first one,and saw the next absolutely covered in green mold.
Mold in modern houses is often from people going gung-ho on energy efficiency without paying attention to ventilation and forgetting that humans are moisture factories. Seal up a house too much and everything works fine as long as it is empty .. add humans sweating and breathing, and you get moisture/mold problems.

I would think the top of a hive would need some ventilation. When the box heats up; the warm, moist air will go up, not down. Without creating a convection current, ventilation will be negligible.
As far as the "bees know best" thing ... They didn't build the box, and can't just call a carpenter bee to drill a few holes. They can do the equivalent of caulking, though... So ... if no top entrance, why not try some spacer tabs 1/16" to 1/8" thick at the corners to hold the top a little above the sides of the box (and/or between inner cover)? (4 countersunk screws would give you a gap that is adjustable from zero to 1/2" shorter than the screws) ... If the bees don't like it, wouldn't they start trying to seal it up?

Other thing is the "roof" .. (water takes the easiest route) if roof is not waterproof, rain soaks in, soaks through and can even seep into the inside. A painted top might be water resistant but not water proof ... so it rains and everything seems fine but the wood gets wet under the paint. Sun gets on it later and paint switches from working for you to against you by providing resistance to the water vapor outgassing ... so you get a slightly pressurized area between paint and the cooler,wet wood below.. when there's pressure, something's gotta give.. either the paint breaks and peels or water is pushed through the wood and into the box.

Why would you need an inner cover if there is no top entrance? If anything, why not use a screen instead?

[The15thMember]

Other thing is the "roof" .. (water takes the easiest route) if roof is not waterproof, rain soaks in, soaks through and can even seep into the inside. A painted top might be water resistant but not water proof ... so it rains and everything seems fine but the wood gets wet under the paint. Sun gets on it later and paint switches from working for you to against you by providing resistance to the water vapor outgassing ... so you get a slightly pressurized area between paint and the cooler,wet wood below.. when there's pressure, something's gotta give.. either the paint breaks and peels or water is pushed through the wood and into the box. 

I have definitely had this happen to some of my migratory covers, and as a result they are not only moldy and paint chipped, but warped as well. 

Why would you need an inner cover if there is no top entrance? If anything, why not use a screen instead?

Without an inner cover, the bees would stick a telescoping top down and it would be impossible to leverage it open.  That's why migratory covers don't need inner covers. 

So here's what I'm thinking about doing.  I have a bunch of different potential combinations of equipment (permutations of solid BB, screened BB, solid IC with entrance open, solid IC entrance closed, screened IC, migratory top, telescoping top).  I've got 10 hives at the moment.  I'm going to clean all the tops, and set up as many different combinations as I can.  Obviously there are a lot of variables here (hive location, the particular colony, the weather, etc.), so this won't be intensely scientific but maybe I can at least establish some trends for my apiary.       

[Occam]

My bees climb up into the telescoping cover and still glue it down some, at least have in the past. Since putting the insulation board a coroplast piece in there the edges don't extend down past the edge of the inner cover, so it's more of a really thick migratory cover.