So what's the problem with Oxalic Acid then?

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kazmcc

Queen Bee
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Longsight, Manchester, UK
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None, although I have my eye on one ( Just don't tell Dusty ;) )
I get the feeling I am about to open a HUGE can of worms, but I've been given a quick run down of our plan for the ladies, and it includes a winter treatment with Oxalic. Please remember I have no say ( yet ) over how these bees will be treated so don't tell me off......just inform me please ;)
 
Some swear by it - and some swear about it. I have never done it, as I am in my first year - and admit I hate the thought of trickling acid on my bees - but I'm a newbee so can't truly have an opinion on something I haven't experienced first hand.

I shall watch the comments from a distance - fireworks scare me...
 
I used it last winter and on new swarms this season (caught swarms not from my hives), and saw no ill effects.

From what I have read and heard, it pays to get the recipe right - too strong and the knock down rate of bees will be as high as the varroa!....but, in the right dilution, works a treat. The one caveat seems to be not to use it more often than every 3 months(can't see why anyone would want to though)...presumably because it may have an effect if used on the same bee too soon. It seems that an annual dowsing doesn't bother the queen.....there may be repercussions when treating an early swarm if that same queen has been treated in the winter....a gamble, and not the end of the world.

Treat the colony when there is no brood, very good knock down rate, gets them started in the spring with very little varroa messing things up for them.

Having a trawl with the help of google, I'm having difficulty finding much negative about varroa treatment with oxalic acid.
 
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I spent some time looking into this as it's frequently mentioned at my local BKA meetings. It's one of the more "organic" treatments, but of course that doesn't mean it's cuddly and green and harmless. It's very poisonous to humans, not to mention bees themselves, and has to be measured out and applied with great care.

It has some advantages: it does kill a lot of mites, and it should be possible to avoid damage to adult bees if used very carefully. It's unlikely to kill off the queen, and apparently doesn't cause too much distress. It doesn't leave too much in the way of residues either, at least not when compared with "synthetic" treatments, and very tiny amounts may occur naturally in honey, so it's not totally alien to the environment. Having said that, I personally wouldn't touch it with a bargepole for the following reasons:

Firstly, it's an outrageous sledgehammer-to-crack-a-nut! It really is dangerous to humans, not just Health and Safety Executive, nanny-state -type "hazardous", but quite capable of causing death and severe skin damage even from a small portion of one bottle of hive treatment. Why bother with it??

Secondly, it can only really be used on a cluster of adult bees as it doesn't kill varroa in brood cells, so if you're in a mild part of the country there's a possibility that you'll still be carrying some varroa into spring in brood cells unless you do several intrusive treatments. Plus, a trickle treatment is hard to control in terms of the amount that each bee gets, so some overdosing of individual bees is likely. Not nice for the bees.

Thirdly, it's a real faff, what with face masks, gloves, keeping the unused acid secure, getting the dose just right, filling syringes etc. Having poisons around the place is always a responsibility. Bore.

If I really felt that the winter cluster of bees was in trouble and needed varroa treatment before spring, I might be tempted to use lactic acid, which has much of the advantage of oxalic acid and reduced disadvantages. Measured doses can be sprayed on and it appears to be less unpleasant all round. Still a hazardous chemical though, very nasty for the bees, and not something I'd undertake lightly.

Of course, the other argument might be that varroa is also nasty for the bees, and what's more can be spread from your bees to other peoples'. I suppose it's up to individual choice in the end.
 
As a fellow newbeek I'm in two minds as to whether I'll be applying this winter. However the lecturer that taught me (24 year experience) recommended it, as does a local large producer and the bee inspector - so my inclination was to do it.

However, mite fall to date has been small so may still hold back this year.

The idea of trickling acid seems inheritantly wrong, but have there been any studies showing detrimental effects to weigh up the percieved benefits?
 
The one caveat seems to be not to use it more often than every 3 months

Absolutely only once a year!!

With a correct solution I have used it for the last 3 years with no ill effect on my bees and a good result on varroa death.
You can buy the solution already made up from a supplier- apply slightly warmed 5 mls per seam of bees.
I make up my own solution - disposing safely any unused within that day.
 
Oxalic Acid occurs naturally in low doses in a wide variety of plants and animal tissues. Found in minor poisonous plants such as Rhubarb (do not eat the leaves!). It is not a strong acid such as HCl but it is a strong bleaching agent and it main use in industry is bleaching wood and paper pulp. As a bleach it is dangerous to handle but since Beeks are using it as a 6% solution it is not too difficult to handle and use, so long as you take adequate precautions as, of course you do, with any household type bleach. Think Bleach Think Oxalic Acid.
 
So I suppose the problem would lie with the queen, who, if using the same girl for two years, would end up with two doses, whereas the bees would be exposed to it once. What would you do about that? Does it matter that she would get dosed twice?
 
As a fellow newbeek I'm in two minds as to whether I'll be applying this winter. However the lecturer that taught me (24 year experience) recommended it, as does a local large producer and the bee inspector - so my inclination was to do it.

However, mite fall to date has been small so may still hold back this year.

The idea of trickling acid seems inheritantly wrong, but have there been any studies showing detrimental effects to weigh up the percieved benefits?

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.

Again this year there has been hardly any natural drop, but I still think I will do an oxalic acid treatment even if its just for comparison.
 
I've said this somewhere else on this site today but it is worth repeating. A beefarmer I know in Finland has over 2,000 colonies and the only varroa treatment they get is a winter trickle of oxalic acid/sugar syrup. Because of the very long broodless period in the Finnish winter the treatment is so effective he needs no other treatment in the short summer. This does not apply in the UK where a late summer treatment of something like thymol is needed to hit the varroa again.

The point is for those worried about oxalic acid, the bees are thriving and he gets huge crops of honey.
 
I dont have a problem if others want to use it in their apiaries but I won't after reading up about it.

For example

Potential Health Effects


Oxalic acid is corrosive to tissue. When ingested, oxalic acid removes calcium from the blood. Kidney damage can be expected as the calcium is removed from the blood in the form of calcium oxalate. The calcium oxalate then obstructs the kidney tubules.

Inhalation:
Harmful if inhaled. Can cause severe irritation and burns of nose, throat, and respiratory tract.
Ingestion:
Toxic! May cause burns, nausea, severe gastroenteritis and vomiting, shock and convulsions. May cause renal damage, as evidenced by bloody urine. Estimate fatal dose is 5 to 15 grams.
Skin Contact:
Can cause severe irritation, possible skin burns. May be absorbed through the skin.
Eye Contact:
Oxalic acid is an eye irritant. It may produce corrosive effects.
Chronic Exposure:
May cause inflammation of the upper respiratory tract. Prolonged skin contact can cause dermatitis, cyanosis of the fingers and possible ulceration. May affect kidneys.
Aggravation of Pre-existing Conditions:
Persons with pre-existing skin disorders or eye problems, or impaired kidney or respiratory function may be more susceptible to the effects of the substance.

I wouldn't want to expose myself to it, so I think its cruel to force it on to any of my colonies.
 
Read the safety sheets for acetic acid .
This will also scare the pants off you , but Hey! a 4% solution goes well with my french fries :redface:

John Wilkinson
 
The 3.2% OA solution used by beekeepers is not particularly hazardous. I wouldn't want it flicked in my eye but the fact that it does not kill bees when used correctly shows how relatively harmless it is - other than to varroa but even they don't usually start dropping out of the hive until 24 hours have passed.

You have to ask yourself is it more cruel to leave the bees to be fed on by the varroa or to give them a dribble of luke warm sugar syrup containing a very diluted acid.

There are probably shampoos with lower pH values.
 
As my hives are on a farm, and as it is a poison, if i was to use this, would i need to advise the owners of the property?
 
Read the safety sheets for acetic acid .
This will also scare the pants off you , but Hey! a 4% solution goes well with my french fries :redface:

John Wilkinson

Nice

Acetic Acid

Emergency Overview
--------------------------
POISON! DANGER! CORROSIVE. LIQUID AND MIST CAUSE SEVERE BURNS TO ALL BODY TISSUE. MAY BE FATAL IF SWALLOWED. HARMFUL IF INHALED. INHALATION MAY CAUSE LUNG AND TOOTH DAMAGE. FLAMMABLE LIQUID AND VAPOR.


Health Rating: 3 - Severe (Poison)
Flammability Rating: 2 - Moderate
Reactivity Rating: 2 - Moderate
Contact Rating: 4 - Extreme (Corrosive)
Lab Protective Equip: GOGGLES & SHIELD; LAB COAT & APRON; VENT HOOD; PROPER GLOVES; CLASS B EXTINGUISHER
Storage Color Code: Red (Flammable)
-----------------------------------------------------------------------------------------------------------

Potential Health Effects
----------------------------------

Inhalation:
Inhalation of concentrated vapors may cause serious damage to the lining of the nose, throat, and lungs. Breathing difficulties may occur. Neither odor nor degree of irritation are adequate to indicate vapor concentration.
Ingestion:
Swallowing can cause severe injury leading to death. Symptoms include sore throat, vomiting, and diarrhea. Ingestion of as little as 1.0 ml has resulted in perforation of the esophagus.
Skin Contact:
Contact with concentrated solution may cause serious damage to the skin. Effects may include redness, pain, skin burns. High vapor concentrations may cause skin sensitization.
Eye Contact:
Eye contact with concentrated solutions may cause severe eye damage followed by loss of sight. Exposure to vapor may cause intense watering and irritation to eyes.
Chronic Exposure:
Repeated or prolonged exposures may cause darkening of the skin, erosion of exposed front teeth, and chronic inflammation of the nose, throat, and bronchial tubes.
Aggravation of Pre-existing Conditions:
Persons with pre-existing skin disorders or eye problems, or impaired respiratory function may be more susceptible to the effects of the substance.
 
As my hives are on a farm, and as it is a poison, if i was to use this, would I need to advise the owners of the property?

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!
 
Thanks rooftops, just wanted to make sure i was not going to upset the owners or bother them unnecessarily, if i decide to go down this root. Like you say though, where do you stop?
 
You have to ask yourself is it more cruel to leave the bees to be fed on by the varroa or to give them a dribble of luke warm sugar syrup containing a very diluted acid.

There are probably shampoos with lower pH values.

I understand your point of view John, but OA is imho one step too far considering what they have to deal with already with my IPM.
Autumn and Spring treatments and shook swarming every two years plus the other less effective methods through out the year like feed additives vitafeed green/gold and sugar dusting.

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.
 
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As an aside, calcium oxalate precipitation (because it is very insoluble) is the classical gravimetric/volumetric method of analysing the purity, or composition, of calcium compounds. Done it quite a few times 40 years ago. The method is not used so often these days!!!

Regards, RAB
 
i saw it used last year and the colonies are fine this season so i think i will be using it
 

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