When to treat with oxalic acid?

[Finman]

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Remember basic dosage. 100 g water + 100 g sugar + 7.5 g OA.
That is for 5 one box hive or to 3 two box hive.

Mixture will be 1.6 dl.

 

[Roola]

Disolve 1kg sugar in 1 litre of water. This produces 1.67 of 1:1 (100%)syrup. Add 75grm of Oxalic Acid. This gives a 3.2% Oxalic Acid (weight/volume) solution which is more commonly expressed as 4.5% Oxalic Acid solution.

What I've always used anyway - you can pro rata down the quantities to whatever you need

Thankyou having now spoken to a knowledgeable beekeeping friend I may look to join the vaporising camp. Question to you, I predominantly use Swienty Poly hives and am concerned as to how I might slide the tray through the entrance, I don't think it would be even possible without some melting happening... so under the mesh floor is my thinking however the mesh you get with the swienty hives I think is pretty crap and I was wondering if people have done this and if the vapour makes it through it into the hive or whether it condenses onto the mesh and doesn't make it through. If it does appear to work I was looking at the Varrox as a late Christmas Present to myself... would people say these are the better option?

So in brief:
Does vapour from oxalic acid make it through original mesh floor of swienty hive successfully?

Which piece of kit would you recommend for the job?

Thanks!

 

[beeno]

Hi Roola,
Wishing you and your family a happy new year. Don't forget to swat up on the human safety issues if you go down the vapping route.

 

[TryingToLetThemBee]

Thankyou having now spoken to a knowledgeable beekeeping friend I may look to join the vaporising camp. Question to you, I predominantly use Swienty Poly hives and am concerned as to how I might slide the tray through the entrance, I don't think it would be even possible without some melting happening... so under the mesh floor is my thinking however the mesh you get with the swienty hives I think is pretty crap and I was wondering if people have done this and if the vapour makes it through it into the hive or whether it condenses onto the mesh and doesn't make it through. If it does appear to work I was looking at the Varrox as a late Christmas Present to myself... would people say these are the better option?

So in brief:
Does vapour from oxalic acid make it through original mesh floor of swienty hive successfully?

Which piece of kit would you recommend for the job?

Thanks!

I have used a Varrox for two seasons and it has been well worth the 20-ish jars of honey; almost certainly paid for itself in year one. In London, I have BIAS now, based on a quick inspection I made of a nuc on 19th, so you might well have sealed brood for at least 3 weeks. The heating is at the end and the handle has some insulation, so the trick to not melting is to wait as the hot end cools. I would go that route rather than through the floor; I am treating said nuc through the floor and it seems a bit erratic; a solid "underfloor" and newspaper stuffed in the gaps helps.

 

[Honeybeeco]

Thankyou having now spoken to a knowledgeable beekeeping friend I may look to join the vaporising camp. Question to you, I predominantly use Swienty Poly hives and am concerned as to how I might slide the tray through the entrance, I don't think it would be even possible without some melting happening... so under the mesh floor is my thinking however the mesh you get with the swienty hives I think is pretty crap and I was wondering if people have done this and if the vapour makes it through it into the hive or whether it condenses onto the mesh and doesn't make it through. If it does appear to work I was looking at the Varrox as a late Christmas Present to myself... would people say these are the better option?

So in brief:
Does vapour from oxalic acid make it through original mesh floor of swienty hive successfully?

Which piece of kit would you recommend for the job?

Thanks!

We have started to used the varrox on our hives through the the year where needed and it's a nice tool, which works well, and is easy to use. We use wooden hives so don't have experience of the Varrox with poly hives, but with regards using it under the mesh floor, you have to remember OA is corrosive so if the mesh floors you have are of poor quality, a few uses of the oxalis acid via the varrox under the OMF could lead to the floor becoming useless and corroded.

Coincidentally, We are testing one of our OMF using the Varrox under it at the moment, doing repeated tests in our storage shed on the bench, to see what exactly does happen with regards it actually eating through the galvanised coating and also the steel. We are looking at it as It would be easier if we can slide it in the backdoor via the Omf than take off the mouse guards on the number of hives we have. It was noticeable on the first use via the OMF that the mesh floor showed immediate discoloration from OX but I'm having a few weeks off so the boys at wok are running the test for us. When I'm back to work in January I'll report back with how it goes.

 

[Roola]

Thankyou, really interesting reading! I would think the heat will also discolour the metal too. I'm not super fussed at present if the mesh floors are damaged as i'll be doing a phased replacement with better quality stuff but long term i'd be interested to see if there is much of an adverse effect, would prefer to treat under OMF from the rear.

 

[Cussword]

would prefer to treat under OMF from the rear.

That's pretty much what I do, I have under floor entrances on my wooden hives.

 

[Arfermo]

I started beekeeping with advice to a newbie that trickling oxalic was the only way to go. However, I used my own judgement as to the interference with the bees that that involved, opening the hive in cold weather, sloshing a potentially cooled liquid upon the poor little devils, bees flying when they would prefer not and potential stings and clusters of bees on my shoulders trying to benefit my bodily warmth, and got myself a Varrox and the crystals and sold the solution and the syringe that I had bought to someone else.
The first year I did "what it says on the tin" and shoved it in though the entrance to roughly the centre where the cluster was most likely to be with the consequence that a few bees got fried to a crisp too. Ever since then for nearly a decade I have placed the Varrox below the mesh floor on a metal sheet that I slide in where the varroa tray goes with the remainder of the aperture stuffed with foam. I may wear glasses and be quite a bit beyond the fortieth anniversary of my fortieth but I am sure I would have noticed a problem with the mesh - ALL of them remain in very good nick. All my mesh floors are National style from Wyxne Joxes and are almost certainly big T's products. Need I say more - good quality. I therefore suggest that sublimation below the OMF is the way to go for as long as there is no better alternative, say by modifying the genetics of the beastie. OK?
As to where to get a Varrox - cheapest I have found was last year at the Spring Convention. £100 as compared with £140 from you know who. Cheaper alternatives exist as has been mentioned elsewhere in this forum and they look as good too. Your choice.

 

[Finman]

.
The issue has been missed badly.. When to trickle?

.trickling is very good method and it is used in warmer countries than Britain.
Gasifying does not make it worse.

Broodless is the key word in every place. You can use it even to swarms in summer.

 

[TryingToLetThemBee]

@Honeybeeco ; please let us know how you get on. But well, I would have thought; OA is a metal TREATMENT in contrast to, say, salt. eg http://www.google.co.uk/patents/US4316752

 

[GillGM]

Vapping

For those of us who don't use vapourised (up to now) what is involved? I have an out Apiary so have no access to power and use open floors. I think hives have to be sealed?

 

[deanrpwaacs]

I think it could be time for a sticky thread with what is involved/required for vaping . There are some shocking videos on line with no regards for safety . I understand what is required from reading several posts but it could be of use to a newb . Just an idea .

 

[jenkinsbrynmair]

For those of us who don't use vapourised (up to now) what is involved? I have an out Apiary so have no access to power and use open floors. I think hives have to be sealed?

Sublimated oxalic acid rises, so no real issue - it is more important that the hives are closed up whilst doing it and for ten minutes afterwards to ensure as many bees as possible get covered with the desublimated crystals - they can then spread it to the few that were out flying.

The varrox and similar use 12 volt power so can be operated using a can battery.

 

[Arfermo]

I think hives have to be sealed?

That is what the Varrox instructions say and you can read them on-line. As for sublimation - no big deal. Never done it any other way and never had a problem with bees or self. Bit of self-confidence, reading up on possible problems without taking too much of the negativity that abounds, and some practical common sense is quite enough. Speed and proficiency come with practice and your bees definitely will benefit from it. It astonishes me how long it has taken for supposedly experienced beekeepers to at last be taking sublimations seriously and who, after minimal experience, now claim to be so knowledgeable that they are the authority on the subject on this forum.

 

[Erichalfbee]

For those of us who don't use vapourised (up to now) what is involved? I have an out Apiary so have no access to power and use open floors. I think hives have to be sealed?

I have found it so easy.
I have modified my floors by increasing the depth under the OMF to make it easier.
Block up the entrance.
Slide in a metal tray under the OMF
Attach Varrox to one terminal of the car battery( I can get the car to the hives but if you can't a scrapped car battery in good condition is a viable alternative and will hopefully do six hives....somebody will correct me if I'm wrong on the number)
Pop in premeasured amount of Oxalic. The amount depends on the size of your box but isn't critical.
Slide Varrox under OMF
Block off the back with foam or towels or suchlike.
Clip leads to other terminal and time....that depends on the amount of oxalic. I use 3g and heat for 3.5 minutes.
Take out.
Re-block the back of the hive.*****
Dip varrox in bucket of cold water to cool it and move straight onto next hive.
Instructions say to keep hive blocked up for 10 minutes but I have found 6 is enough.
***** is where you should really have some decent particulate mask as some vapour does escape as you withdraw the Varox and you don't want to be breathing any in.

 

[rugbee]

That is what the Varrox instructions say and you can read them on-line. As for sublimation - no big deal. Never done it any other way and never had a problem with bees or self. Bit of self-confidence, reading up on possible problems without taking too much of the negativity that abounds, and some practical common sense is quite enough. Speed and proficiency come with practice and your bees definitely will benefit from it. It astonishes me how long it has taken for supposedly experienced beekeepers to at last be taking sublimations seriously and who, after minimal experience, now claim to be so knowledgeable that they are the authority on the subject on this forum.[/QUOT

But experience in beekeeping will help to make decisions with regards the bees and whether or what best treatment suits you and your bees
Sublimation is hardly a subject more a method of application of a pesticide of which there are two more ( as I'm sure you know) all I'm sure have their merit
I've trickled OA years ago when I first got resistance trouble but for me it did not suit that doesn't mean it didn't work
For me I have no intention of using OA in any form at the moment as it for me is costly and has mixed results but that i can't stress enough after paying the price of overuse of apistan that OA should be used as part of a mixture of different treatments

 

[linoleum bonypart]

Just got my vape set up all ready...Inc a small luggage trolley to wheel battery to hives

 

[djg]

I've just had >300/hive mite drop per hive 3 days after trickling. (Full Apiguard went on in late August)

Just to say that people shouldn't be put off treating with oxalic at this time of year, whatever the merits of sublimation v. trickling, whatever the outlook for the temperature, now that the Winter Solstice is over a week behind us.

If those 300 mites were still in the hives untreated, there would be overwhelming varroa infestations by late Spring....and even if the efficacy of my oxalic was below the 95% optimal level, given that some mites will be in the brood cells, the alternative is too grim to contemplate.

 

[Finman]

I've just had >300/hive mite drop per hive 3 days after trickling. (Full Apiguard went on in late August)

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Most of mites will drop during first 2 weeks. Third day is only beginning. dropping continues one month.

 

[Finman]

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Glasgow forecast for next 10 days. +5 - 0C and rain every day.
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Foraging will be interrupted.