So what's the problem with Oxalic Acid then?

[Monsieur Abeille]

Last year the natural mite drop on one of my hives was minimal, but an oxalic acid treatment between Xmas and New Year knocked down several thousand.

Thanks sixfooter, think thats me convinced.

 

[RoofTops]

If I go over to plastic frames for all my hives then I'd shook swarm them ever a year which will make a massive dent in Varroa numbers.

I shook swarmed onto plastic frames this year and was caught out by one colony which still had massive numbers of mites. The problem was there were no frames of unsealed brood to put in as a bait frame - they all had plenty of sealed as well but I thought there shouldn't have been too many mites on the bees themselves - I was wrong.

I zapped them with formic acid but not until several weeks had passed because that was how long it took me to realise they still had a serious mite problem. I used formic acid so it would attack the mites in sealed brood as I felt drastic action was called for. Hundreds of mites fell out over a week.

In hindsight I should perhaps have given them - wait for it - OA syrup straight after the shook swarm. This is what I would probably do next time but thymol could also have been used or formic acid of course.

 

[MuswellMetro]

I am not anti Oxalic but i am extremeley allergic to it, if i eat Rhubard crumble i swell up in the throat and cannt breath, if ipick rhurbard leaves my hand swell

So i do not use oxalic acid

i use lactic acid, not as good as you need two application in Decmeber and you need to spray the Bees not just trickle , and the hive is open longer and you break the ball of bees

but you can apply it more than once

but saying i am considered getting a freind to treat one of my hives with oxalci this year just as a trial ( thats on FINMAN's advice)

Does anyone else use Lactic Acid

 

[Hivemaker.]

Because oxalic damages the bees, it damages the queens, and dribbling oxalic does damage the bees,causing irreparable damage to there internal organs,malphigian tubules ect.
You can only do one dose as two will shorten their lives too much. If two does too much damage then one is doing some damage,and especially to the queen as she could be expected to have 3 doses or more.
As for shook swarming.....in my view thats for people who have completely failed in all other methods of controlling something as simple as varroa.

 

[Repwoc]

Gardenbees and Mike A:

I think you're both being a bit ridiculous about this. The winter OA treatment is one of the most effective and easy to apply varroa treatments available and posting emotional and scary rants like you have done will put new beeks off, which can only lead to more colonies suffering and dying unnecessarily from varroosis.

There has been extensive scientific research carried out on treating bee colonies with dilute OA+sugar solutions (search the forum for links) and the benefits far outweigh the drawbacks. Treating the bees with it is far from being a major faff - once the solution is made up (easy), all that is necessary is to squirt 5ml of it along each seam of bees. I use a 5ml syringe (easy to obtain) to do this and each hive takes about one minute (max) to treat from roof off to roof back on.

While it is important to be careful when using any chemicals, small amounts of oxalic acid are not dangerous to the average person. When handling the solid or strong solutions I would advise wearing rubber gloves and safety specs, although personally I don't bother. (I don't wear them when cleaning the toilet either and I consider bleach and toilet cleaners to be more hazardous than OA.) OA is soluble in water so any that gets on the skin can easily be washed off.

OA is widely available as a wood bleach and general cleaning agent (eg for boats). It is good for removing rust stains from fabrics (used it a lot for that) because of its ability to chelate iron. It isn't a controlled substance and you don't need a licence or anything to buy it.

As has already been mentioned, OA occurs naturally in many plants and even in honey, so proclaiming it to be a deadly poison is, in my opinion, just scaremongering. The average person would need to consume a significant amount of the solid to suffer death, and I bet it doesn't taste too good so not something that will happen easily/accidentally. Take a look at this page for more information:

http://www.rhubarbinfo.com/poison

Note the bit about vitamin C. It is metabolised to OA - shock horror! - so whatever you do, don't eat any more fruit and veg. Oh, I forgot, you'll get scurvy instead.

 

[gavin]

I do recall seeing some evidence that it damages the worker bees (as does Varroa of course), but does this necessarily mean that it damages the queen? I would imagine that she isn't as exposed to the full effects as she doesn't access the syrup directly.

Fresh rhubarb leaves are around 0.5% oxalic acid, so the 3.2% usually used is just over 6 times stronger. Worth handling carefully and definitely in solution only but not terrifying stuff.

I'm happy to use it, and even to pass it round colleagues in the local association.

G.

 

[Hivemaker.]

But what feeds the queen.....the attendants...they consume the oxalic mixture, and there are many of them feeding the queen...plus of course the treatment may also dribble directly over the queen at time of application.

 

[Monsieur Abeille]

As for shook swarming.....in my view thats for people who have completely failed in all other methods of controlling something as simple as varroa.

Bloomin heck, I didnt realise that was controversial as well - had been happily planning to do one in the spring as a means to swap hives as well as (my percieved) benefits of IPM and swarm prevention.

I feel another thread coming on in the not too distant future!

 

[kazmcc]

So for those of you who won't use OA, what do you use? Or what methods do you use?

Isn't Apivar and other types of this treatment used for varroa? So why do you need to treat with so many things?

 

[gavin]

There ain't nuthin' in beekeeping that ain't controversial M. Abeille!

Pete - I'll bet that the queen gets stuff that is diluted slightly and only enough for her needs at the time whereas the other workers will hoover the stuff up as that is what workers do with syrup.

The bottom line - for queens - is has anyone noted queens living less long when oxalic is used?

G.

 

[gavin]

Kaz, I'll bet that many use thymol, as Hivemaker does. Now the odour from that is something to behold, and it *does* clearly affect the bees whereas there is nothing that you can see happening when oxalic is used.

I'm with Rooftops - freeing them effectively from Varroa is a kindness.

PS just to be clear I'd rather use neither but for the bees' sake I use both.

 

[susbees]

Who decided that 3.2% was the "best" dilution?

 

[Monsieur Abeille]

So for those of you who won't use OA, what do you use? Or what methods do you use?

Isn't Apivar and other types of this treatment used for varroa? So why do you need to treat with so many things?

Kaz - as there is no complete cure for varroa, the accepted (I think!) thing to do is IPM, or Integrated Pest Management. This comprises of many different "treatments" such as OA, Thymol, Drone brood removal, Shook swarming, Icing sugar, OMF etc etc - some of which complement eachother, some of which act in isolation.

Not everyone, clearly, does all of the treatments (and some apparently do none!), but the theory as I understand it is that by combining these treatments varroa levels have a chance of being kept to a minimum

Did I get that right?

 

[aseeryl]

Not much mention of vapourising OA crystals. I've seen adverts for (expensive) vapourisers, but you can make your own cheaply. Need to seal up the hive etc.

Is this a weird habit that foreigners inflict on their colonies?

BTW Wimps, please never drink fortified wines, famously port - it contains oxalic acid but it takes a lot more than the sniff of a cork to cause gout or kidney failure.

 

[gavin]

Is this a weird habit that foreigners inflict on their colonies?

It is certainly a weird habit of a set of Scottish beekeepers if they (we!) count as foreigners. Perhaps they were influenced by enthusiastic promotion of it by the ex-editor of the Scottish Beekeeper.

I think that the battery, cables, odd apparatus (or even copper pipe and blowtorch) appeals to a certain kind of person, but as Rooftops said they ought to be dying out quite soon!

G.

 

[RoofTops]

Who decided that 3.2% was the "best" dilution?

There has been extensive research in Europe on the use of OA syrup. A stronger solution is used in southern Europe.

 

[aseeryl]

It is certainly a weird habit of a set of Scottish beekeepers if they (we!) count as foreigners. Perhaps they were influenced by enthusiastic promotion of it by the ex-editor of the Scottish Beekeeper.

Is it a niche thing then?

I'd never heard of this method of application till recently. Seemed like an OK idea and I was thinking of giving it a go.

 

[gavin]

One advantage folk claim is that you can use sublimation more than once per winter. One well-timed dribble is just as good.

Dribbling:

- is safer for the operator, no need for face masks
- doesn't need expensive kit
- easily portable bits and pieces, no heavy carrying
- well tolerated by the bees

G.

 

[Arfermo]

QUOTE=RoofTops;76974]Oxalic acid is approved by the Soil Association for organic beekeeping so I would very much doubt the owners of the farm need to be troubled - especially as the OA is only going to be used within the hive. Remember the OA is heavily diluted - except for those still vaporizing the stuff but they will all kill themselves eventually so that method will hopefully vanish. OA is poisonous when used incorrectly but sensible precautions are all that need to be taken. It is not cyanide.

The treatments people put on their wood hives are also probably poisonous so where do you stop? My car uses petrol - help, its a poison![/QUOTE]

What utter tosh has been written in this thread. I have no hesitation in recommending a Varrox evaporator available from Thxxxxs costing £93.46 + shipping. I commend it to anybody providing one can get hold of one, though not at retail prices circa £110. I got mine S/H virtually unused by a beek who had to give up. They are out there if you look. However, there is a cheaper one which is equally good is the Heilyser Vaporizer. I would only recommend the JB600 model, as the other one is another of the nasty DIY plumbing things. The current price in the US is $64 + shipping $7.20 and you can get quotes for UK delivery by email. An electrically operated evaporator operating from a 12volt source has a minimum 5-metre lead which can be extended further if one wishes, keeping one well out of any danger from the fumes.

As to the relative efficacy of OA treatments, have a look at the Scientific Beekeeping site which offers really detailed guidance. Evaporation has the benefit of more efficient distribution of the OA and infinitely less disturbance to the bees, which, as a hobbyist, is more important to me than any other consideration. What is more, repeat treatments are actually recommended which is not the case with trickling though I don’t see why. On one hive with a drop of 3000 (thousand) mites after the first evaporation treatment, I gave them another dose and then a third to get the mite level down to a reasonable level without any ill effects whatsoever. In fact my enquiries indicate that I have had a better average honey crop this year than anybody else in the local association with colonies bursting at the seams on brood and a half. The instructions for the Varrox vaporiser actually says that one is NOT limited to a single burst as with trickling and as for safety, just get upwind of the hive you are treating. Is that too simple? The other significant fact is that the method of treatment does not require one to open up the hive at all, and since Oxalic treatment of any sort must be done in or around the middle of the dormant season (unless one has devised a swarm or caught one of course) maintaining the comfort of the cluster is important. Why chill them if one doesn't need to. The usual evaporation method is to poke the gadget into the hive via the entrance. However, by putting a sheet of thin steel into where the drop tray goes, I vaporise from under the mesh floor, thus even less interference within the hive. Oxalic trickling or evporation is a must, be in no doubt about that as even FERA recommend it.

 

[Hivemaker.]

I know we don't yet have ccd....but they seem advise not to use oxalic.


5. If you observe high levels of varroa mites, treat them using soft chemicals, such as Apiguard, Apilife VAR, or MiteAway II. We DO NOT recommend the use of oxalic acid, or home made hard chemical mixtures.

Why? Colonies experiencing CCD have been shown to have kidney (Malpighian tubule) problems similar to those seen in colonies treated with hard chemicals. There are some reports that Oxalic acid may damage bee Malpighian tubules. Also the harder chemicals (fluvalinate, coumaphos, and amitraz) may have a sub lethal affect on bees which may add additional stress on the bees. By treating for varroa mites with soft chemicals, you are helping to keep the colonies mite population low while avoiding the potentially negative effects of hard chemicals.
This document was released on March 7 2007 and prepared by Dennis vanEngelsdorp, M. Frazier, and D. Caron at the direction of the CCD working group.