mould in hive

[JamesM]

Hi
This my first post, and my first winter with bees.

I have put fondant over the crown board on each of our 2 hives, and on one there was an empty super over that, giving space to the fondant, and I thought the extra air would provide a degree of insulation against this cold.

Yesterday I lifted the roof to see if they were eating any fondant (they're not) - and I found mould growing inside the empty super. Just your ordinary green mould (and what might be mildew on the outside).

The super is treated with boiled linseed oil - which I thought at the time would be more `natural' than commercial wood preservatives (I've since found that's not so clear).

Is the mould unusual - or anything to worry about? I have now removed the super and replaced it with a wooden feeder (Adam's feeder?) - upside down. Much like an eke.

Any comments?

Thanks
James

 

[Polyanwood]

Possibly damp. Bees don't like damp. Are you on an open mesh floor - if so make sure you have taken out the varroa tray.

Have you insulated your hives too??

 

[JamesM]

Open mesh floor - yes
Varroa tray - no
insulated hives - no

(I guess the crown board reduces ventilation? It's main hole has a box of fondant over it, but the small hole is open - just covered with wire mesh)

 

[Poly Hive]

James?

Open floors began in the UK with poly hives which is a pretty broad hint that top insulation is required.

Mesh floor and top insulation go hand in hand.

PH

 

[rae]

Here's how it works.

The bees produce lots of water vapour as they consume stores (sugar = energy + CO2 + Water). The cluster is quite warm, so the water stays as vapour.

As the warm vapour hits a cold surface, the water condenses (just like your bathroom windows). This happens on the walls of the hive (no problem, it just runs out), and can happen on the crown board (bit of a problem as the water drips on the bees).

With a big empty super up top, you've created a cold void for the vapour to flow up into...and condense. So your super is damp and goes mouldy.

I would remove the super, and put a bit of kingspan or similar into the roof. If you need space to add fondant, use a small eke.

We ran uninsulated roofs last season and the top of the crownboard was similarly covered in mould. This year all the hives have kingspan in the roof and there is not a sign of mould - the roof space remains warm enough for the water not to condense.

 

[Black Comb]

I have a large colony with a fondant tub on the crownboard in a "cut out" of kingspan. Enclosed in a super (it's a decent sized tub) and then roof. OMF with slide out.

When I checked the fondant yesterday noticed that on the crownboard underneath the kingspan was starting to go mouldy?

Any ideas why?

 

[Hivemaker.]

Damp.

 

[Black Comb]

Agreed but why is it damp under the kingspan?

 

[MuswellMetro]

Open mesh floor - yes
Varroa tray - no
insulated hives - no

(I guess the crown board reduces ventilation? It's main hole has a box of fondant over it, but the small hole is open - just covered with wire mesh)

i would not worry too much, yes you could put a 460x460mm 2" block of insulation above the crown board,i do, but i haver found most wood in my hives that i have used linseed on in the past goes mouldy without BEE anywhere near it, so i no longer use it

the colderst part of the hive is going to be the outside wall or above the crown ( if the feed hole is blocked with fondant), therefore on the cold surface you get condensation+ linseed = mould

 

[oliver90owner]

Remove the top ventilation. End of damp in roof (provided the roof is vented). Insulation over the crownboard would be good.

RAB

 

[JamesM]

Thanks for the replies/suggestions.

I've read that linseed seals the wood, whereas preservatives don't. Sealing it means the wood can't breathe, so I wonder if that's relevant. Next super I buy I'll treat differently and see.

 

[Queens59]

In my WBC I filled a lift with polystyrene for insulation - and it has given the bees something to do...chewing the edges all winter!

 

[JamesM]

Thanks

 

[Poly Hive]

Are you going to apply insulation above the CB James?

PH

 

[Hombre]

Raw linseed oil is a great product, but it's not only used in feed for horses. It is a nutrient for fungus too, so needs to be used in combination with a fungicide so that it doesn't support fungus growth in damp conditions.

 

[Polyanwood]

I had some old wax and i did some of my hives in a beeswax/linseed mixture. I now wish i had added some tea tree oil to reduce mould risk.

 

[drex]

James, I hope you only treated the wood on the outside of the hive.

This weekend I was pleased as I came across a tin of old formula cuprinol clear, so I bought it, even though I wil not need it for a few years.

 

[Silly Bee]

In my WBC I filled a lift with polystyrene for insulation - and it has given the bees something to do...chewing the edges all winter!

Not a good idea IMO.

 

[biglongdarren]

i had the same damp patch problem on one of my hives last year...new cedar hive,bare wood,open mesh floor. all i done was set a few matches between the broodbox and the crown board to let the draft through the box...alot of people on here said that it was a bad idea because it left the hive like a chimmey but i tried it anyway,this is my first winter as a beekeeper and the damp has cleared up and my bees are still here....slowly but surely am finding out that bees are alot hardier than i first thought..luck

 

[savoyard]

I found condensation underneath the space quilt on one hive - next to the blocked off feed holes. Glass / perspex / polycarbonate crown boards are not vapour permeable - another reason to start using them...

You still need a ventilated roof though. Damp + no ventilation = dry rot; I lost a roof to it last year, when the vent holes became obstructed.

From my personal notes:-

The old Min of Ag leaflets recommend a 3/4 inch (19 mm) hole in each side of the roof (total area 1134 sq mm)

The BIBBA leaflets show roofs with two such holes each side (total area 2268 sq mm)

A "shop bought" roof has typically 2 slots 25 x 7 mm on two sides (total area 350 sq mm)

Regards

Savoyard