Acetic acid

[OldFarm]

I am debating using acetic acid to fumigate a hive that failed this winter, I've never used it before. There seems to be 2 ways of going about it: bottom up (pad soaked in acetic acid at the bottom of the stack and between each box in the stack, as directed by Thornes) or top down (stack of boxes plus an empty box on top, then a dish of acetic acid in the empty top box). Top down looks like the safer option as it minimises bee keeper exposure. Have seen suggestions of sealing gaps between boxes with tape and putting the stack in a very large bag, wheelie bin type bag. PPE is important, and the view of what's reasonable seems highly variable. Have seen some advise that says wait until the weather is warmer, but other sources don't take temperature into account.

Looking for advise and observations.

 

[elainemary]

I am debating using acetic acid to fumigate a hive that failed this winter, I've never used it before. There seems to be 2 ways of going about it: bottom up (pad soaked in acetic acid at the bottom of the stack and between each box in the stack, as directed by Thornes) or top down (stack of boxes plus an empty box on top, then a dish of acetic acid in the empty top box). Top down looks like the safer option as it minimises bee keeper exposure. Have seen suggestions of sealing gaps between boxes with tape and putting the stack in a very large bag, wheelie bin type bag. PPE is important, and the view of what's reasonable seems highly variable. Have seen some advise that says wait until the weather is warmer, but other sources don't take temperature into account.

Looking for advise and observations.

Hi I’ve used acetic acid for sterilising combs over the last 3 years. Effective against wax moth (never had), chalkbrood (rarely get) and nosema spores. I bought an outdoor toy box and keep 4 old brood boxes that I picked up from an auction for this purpose. I use my mask bought for OA sublimation when using and gloves. I soak c100ml 80% acetic acid in a pad of cotton wool (the cheap folded type you can buy in the baby section in chemists) and put this in a plastic container (eg the type you buy fruit in). Need this amount per full brood box. Place this on top of the brood frames. I loosely wrap a bin liner over the top and the toy box lid keeps the boxes bee free and contains the fumes. Leave it for a few days then air the combs in my bed shed for a few days before reusing. Seems to work well. I’m sure I’ve read somewhere the fumes are heavier than air so I put the pads on top. Evaporates and does it’s job quicker in warm weather. I’ve left a few old combs that need melting down in the toy box this winter with a couple of ‘spent’ pads of cotton wool that have had the acid in, no sign of any wax moth to date either.
Hope this helps
Elaine

 

[Gilberdyke John]

I am debating using acetic acid to fumigate a hive that failed this winter, I've never used it before. There seems to be 2 ways of going about it: bottom up (pad soaked in acetic acid at the bottom of the stack and between each box in the stack, as directed by Thornes) or top down (stack of boxes plus an empty box on top, then a dish of acetic acid in the empty top box). Top down looks like the safer option as it minimises bee keeper exposure. Have seen suggestions of sealing gaps between boxes with tape and putting the stack in a very large bag, wheelie bin type bag. PPE is important, and the view of what's reasonable seems highly variable. Have seen some advise that says wait until the weather is warmer, but other sources don't take temperature into account.

Looking for advise and observations.

Are you proposing to fumigate just the box or combs as well? I simply pour warmed (to liquefy) concentrated Acetic acid into a shallow ceramic or glass dish on a flat hive sized board. Sit the box over it and a flat cover over that. Perspex or glass works well so you can see inside. Patience is required to.let the fumigation work If you're treating hives with frames in you need an eke below the box to provide clearance for the dish. Evaporation does go on when cold but works better when warm. Usual care required when handling corrosives.

 

[oliver90owner]

Noo, don't use glacial ethanoic - it will be solid again in a few minutes. It is much safer to handle when slightly diluted.

Your frame nails, etc will take a thrashing from either ethanoic or by burning sulphur strips. I reckon burning sulphur is more effective as a fumigant.

Pulling the boxes together with a ratchet strap (or two) helps to seal most small gaps - and can allow a taller stack to be fumigated on occasions.

 

[jenkinsbrynmair]

Your frame nails, etc will take a thrashing from either ethanoic or by burning sulphur strips.

It will even blacken the wires embedded in the foundation/comb

 

[hemo]

Main reason I go unwired or use starter strips for my frames.

 

[WoodenBeam]

It will even blacken the wires embedded in the foundation/comb

I’ve stored supers and brood boxes of drawn comb over winter for the last few years sealed up with acetic acid - yes the wires do go black but the bees don’t seem to mind, must be working for this to happen & I certainly wouldn’t want to be a wax moth larva living somewhere within the stack

 

[oliver90owner]

must be working for this to happen & I certainly wouldn’t want to be a wax moth larva living somewhere within the stack

Even water will rust steel. Comb wiring will be more resistant to rusting but not too much extra acidic conditions are required to discolour the surface. I use metabisulphite for sterilising wine bottles - a sniff of SO2 is far worse than a sniff of vinegar (I know which I would prefer to breath in - and it is not the SO2! Apparently it is waxmoth eggs, that can readily survive poor ethanoic fumigation; they don't survive a quick dose of burning sulpur.

 

[Amari]

I’ve stored supers and brood boxes of drawn comb over winter for the last few years sealed up with acetic acid - yes the wires do go black but the bees don’t seem to mind, must be working for this to happen & I certainly wouldn’t want to be a wax moth larva living somewhere within the stack

All my boxes with comb are stored outside so with night temperatures well below freezing this week I'm hoping the wax moths will have been killed. Less certain about WM eggs and Nosema. Temp in my unheated greenhouse two nights ago was -4C.

 

[WoodenBeam]

All my boxes with comb are stored outside so with night temperatures well below freezing this week I'm hoping the wax moths will have been killed. Less certain about WM eggs and Nosema. Temp in my unheated greenhouse two nights ago was -4C.

Ah........but I’m preparing for global warming

 

[OldFarm]

Thanks for the suggestions.

 

[Rory Fields]

must be working for this to happen & I certainly wouldn’t want to be a wax moth larva living somewhere within the stack

Even water will rust steel. Comb wiring will be more resistant to rusting but not too much extra acidic conditions are required to discolour the surface. I use metabisulphite for sterilising wine bottles - a sniff of SO2 is far worse than a sniff of vinegar (I know which I would prefer to breath in - and it is not the SO2! Apparently it is waxmoth eggs, that can readily survive poor ethanoic fumigation; they don't survive a quick dose of burning sulpur.

Thus gas me fearing sulphur AND acetic acid may be necessary to sterilise the mountains of drawn comb I've got