[Brad Harrison]

I bought a hive last fall full of mites so around end of November I got a vaporizer and went to ace hardware and got a can of wood bleach (oxalic acid) and treated my hive, which took a total of probably 2 or 3 min. I have very few if any mites from what i can tell. Very effective, cheap, don't have to worry with contamination of my honey or wax, doesn't kill bees, its simple and easy and mites dont become resistant to it.Why are more beeks not aware of this method of mite treatment? Or if they are aware, why arent they taking advantage of it? Am I missing something?

 

[rsjohnson2u]

Well, it's illegal comes to mind, first and foremost.

 

[RayMarler]

Does not being "approved" for beekeeping uses make using it illegal? I would think not, but I'm not a lawyer or legal consult.

 

[rsjohnson2u]

I'm not either. Not approved=illegal will be a personal choice. We beeks seem to scream bloody murder when someone uses pesticides off label near bees, however. A devil's advocate might say "what's the difference, really?" Just because there's no bag limits or open/closed season for some species of fish and game doesn't make it legal for me to hunt and fish them, at least in my state.

 

[BeeGhost]

Its not legal to use is the only reason that a bee keeper wouldnt use it. I tend to speed, not fully stop at STOP signs, not use my turn signal all the time and I also talk on the phone while driving................and I also use OAV with good results. Am I worried about contaminating my honey............not at all. Id be more worried about the bees working Oleander and poisoning me than OAV.

As for pesticides killing my bees............I would rather use OAV which is SAFE for all stages of bees than to dust with Sevin!!

 

[sqkcrk]

1. All beekeepers don't do anything the same.
2. Education
C. Another new thing to learn how to do.
4. Gotta buy a new toy to be able to use the OA.
5. It can be dangerous if not handled properly. So some folks may be concerned enough not to use it.
6. Not approved for use in beehives, which will keep some from using it.
7. There are so many other miticides on the mkt easier to use.
8. Beekeepers can be independent minded.

 

[Brad Harrison]

Oh so its basically red tap. I looked it up and there seems to be no money in it for anybody so no company wants to spend the money to have it aproved by the government. I think dusting your bees with powdered sugar was or is also illegal for mite treatment.
Well then I wasn't treating for mites I was just vaporizing oxalic acid to listen to my bees buzz, and if I was to take the time and effort to dust with powdered sugar, than I was just trying to sweeten them up a bit as they can get mean when your going through the hive.
If that ticks you off than I hope you don't ever speed going down the road because that's illegal as mentioned above and proven to be hazardous for yourself as well as for others in the vehicle and those on the road with you.

 

[sqkcrk]

Brad, it costs millions of dollars and years of trials and studies to get a product approved and registered as a Pesticide. There isn't enough profit in it for the manufacturer. If OA were approved as a pesticide, or powdered sugar for that matter, then all OA and powdered sugar would have to be labeled as a pesticide. I don't think anyone in the OA and powdered sugar industries wants that.

So it isn't red tape at all, it's business.

 

[BooneCtyBeek]

Mark,

I believe OA has been approved for and used in Canada and Europe for quite some time (and they are more strict with pesticides, et. al. that the USA is). On the outside chance you might know, is OA labeled as you described in those areas?

For those interested, Randy Oliver's site scientificbeekeeping.com has a wealth of information on OA treatment.

 

[Daniel Y]

Well, it's illegal comes to mind, first and foremost.

Can you show on instance that anyone was prosecuted for using it?

I assume you are not a lawyer and neither am I . but here is a different take on the issue.

It is perfectly legal at least as far as I can tell to kill your own bees. I found this out by looking into if it is illegal to poison bees if they are in your house. it is not in that case. In fact from what I can tell if they are your bees you can do with them as you wish. I found nothing that distinguished between being yours because they are in your hive or being yours because they are in the walls of your house.

So although it would be illegal to use a pesticide in a manner that kills someone elses bees. it would not be illegal to use that same pesticide in the same manner if it only killed your bees.

So the use of OA as a pesticide. Is it in fact illegal to use it on your bees in a manner that will only treat your bees?

I understand the issue goes beyond these concerns and includes issues like what is being put in a hive that is used to produce a food product. The bees forage in the area where all pesticides are likely to be used. Adding OA to a hive arguably does not make much of a difference. It will mingle with the Round Up and Seven just fine.

 

[JRG13]

I thought approval was pending here in the U.S. It's an off label use which falls into that legal area which does make it illegal to use that way if you're talking pesticides, but if you're just bleaching your frames and the inside of your hive boxes, well, that's another story isn't it.

 

[crofter]

Being in Canada I can use it without feeling naughty in any way. It works well. I doubt there are very many bee inspectors that are working to the letter of the law on OA unless you have been diddling them around over one of the reportable diseases.

 

[snl]

So the use of OA as a pesticide. Is it in fact illegal to use it on your bees in a manner that will only treat your bees?

Per the EPA, OA is no longer registered as a pesticide. The company or companies that originally registered it as such let the registration expire. So OA right now is just OA. Using it as a mite control is an "off label" use of the product regardless that it works and is used successfully almost worldwide.

 

[JWChesnut]

Oxalic can be hard on bees and queens. I've posted the mortality curve before, so won't repeat myself. It is possible (in careless application) to OD the bees and possible to damage the queen. The minimum effective dos to damaging dose ratio is narrow.

The standard Oxalic use case has changed from once a season to a 3 week course of periodic treatments. This is because of the lack of efficacy under capped brood. The repeated treatments makes the queen death and OD more likely, and raises the labor cost.

Oxalic is irreversible, once applied the crystals reconstitute on the hive.

Formic penetrates caps, and in the case of OD, the hive can be ventilated (and the fumigant removed).

 

[camero7]

1. All beekeepers don't do anything the same. Agree
2. Education
C. Another new thing to learn how to do. Doesn't take long.

4. Gotta buy a new toy to be able to use the OA. Fun part of OA

5. It can be dangerous if not handled properly. So some folks may be concerned enough not to use it. I really think this is overblown. I've been using it for 6 years on all my hives in the fall. never had a problem.

6. Not approved for use in beehives, which will keep some from using it. So are shop towels.

7. There are so many other miticides on the mkt easier to use. I found OAV the easiest of all of them. 60 seconds or so per hive, no lifting, bees aren't disturbed much and no brood/queen damage

8. Beekeepers can be independent minded. Amen

 

[peterloringborst]

The following may shed some light on why the vapor is not more widely adopted: it appears to be no more effective than the trickle, and is much less safe for the operator:

A review article by Rademacher and Harz (2006) summarizes over 50 references related to the use of OA in European countries. Their review article covers the efficacy of OA against Varroa and honey bee tolerance for the trickling, spraying, and evaporating application methods. The trickle and spray methods of OA application were employed in my dissertation research. I chose to exclude the evaporation method due to inherent hazards to the applicator. When OA sublimates, both OA and formic acid fumes are liberated and can permanently damage lung tissues if inhaled. Furthermore, the European literature regarding OA efficacy indicates that the trickle, spray, and evaporation methods of application are equally effective against Varroa mites.

Aliano, N. (2008). An investigation of techniques for using oxalic acid to reduce Varroa mite populations in honey bee colonies and package bees.

 

[snl]

"Furthermore, the European literature regarding OA efficacy indicates that the trickle, spray, and evaporation methods of application are equally effective against Varroa mites."

That's probably true in a broodless hive, but the trickle method does damage brood, OA vaporization does not.

 

[peterloringborst]

That's probably true in a broodless hive, but the trickle method does damage brood, OA vaporization does not.

It's my understanding that oxalic is used during broodless periods since it cannot kill mites inside the brood cells. What evidence do you have of brood damage using either method?

 

[snl]

What evidence do you have of brood damage using either method?

Per Randy Oliver:
Asking around, the jury’s still out, in my opinion as to whether OA summer treatment is worthwhile, due to relatively low efficacy, and demonstrated damage to the brood (see below). The later in the season, and the smaller the brood nest, the more effective the treatment is. In the short term, though, it sure causes a major drop of mites!
Does It Harm The Bees?
Ellis and Aliano found that OA is about 70 times as toxic to mites as it is to adult bees—which is a much greater spread than with either thymol or formic acid. The bees normally do not react defensively to being dribbled with syrup, but on rare occasions run out the entrance for a while. Occasionally one will notice a little adult bee kill after oxalic treatment. Adult bee kill does not seem to be an issue. However, there are questions about subtle effects, larval kill, and lasting suppression of brood development.
As far as winter broodless dribbling, it is absolutely critical to treat them only once, with exactly the right amount and concentration of OA. More than one winter treatment clearly hurts the bees. Charriere and Imdorf (2002) found that colonies treated with 5-6 ml/seam of 3% OA were only 85% the strength of controls by April 25. The best review is in Anonymous (1999). Typically, winter bees treated with OA start out a little slower, but catch up by the end of March.

There is more on his website.

 

[jim lyon]

We used an oxalic trickle this spring on check backs at the 3 week mark after queen removal. They typically had 3 to 5 frames of open brood when treated. A month later these 10 frame singles were wall to wall brood. I wasn't gauging against control hives, of course, but it seemed a typical build up to me based on what we have experienced in previous years when we elected not to treat at that stage. I realize there is research out there apparently proving a reduction in brood volume. I won't dispute there are probably scenarios where this is true but I really wouldn't use it as an excuse not to use oxalic if you feel your mite numbers are high and you have a good treatment window. I have also experimented with trickling several times throughout the summer but I'm not sure it really had much meaningful impact on mite numbers.
To answer the Question posed in the OP? I don't vaporize (sublimate) because trickling is so fast, cheap and effective. We do pallets of 4 singles in about a minute and doubles in a couple minutes and don't have to worry about a breathing apparatus or worry about which way the wind is blowing. Also no need to seal up the entrance and any other openings for a prescribed length of time. My question is why isn't everyone trickling in the fall or 3 weeks after a brood break?