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View Full Version : Oxalic acid as a cold fog????



beelord
09-20-2004, 03:30 PM
I have been reading the chatter on the oxalic acid vaporizers - especially the one from Canada requiring the battery and the heated pan. I have learned a great deal. I have LOTS of beehives and am looking for a faster method of treating with the oxalic acid. I have purchased a cold fog unit that puts out a lot of fog in a short time. I have just started experimenting with it. I diluted the oxalic acid 1pound to 2 gallons of water and fogged into the entrance for a count of 10. Before fogging, I took samples to obtain an approximate mite infestation level for each of six hives by brushing about 100 bees into a jar with some alcohol and then rinsing the bees through a double sieve Dadant honey filter. Only one hive was found to have mites (a 15% mite to bee ratio). I am going to wait 10 days to check my sticky boards for mites after the fogging treatment.

I cannot find any research work or other beekeepers using any methods other than the heat vaporization...which seems impractical to me for thousands of hives.

A German company has a unit that goes on top of the hive that looks very cool, but is still following the heated vapor principle. (http://www.alfranseder.de/)

BULLSEYE BILL
09-20-2004, 10:18 PM
>I cannot find any research work or other beekeepers using any methods other than the heat vaporization

There have been other types of application, misting and dribbling. The misting was from a spray mister, and the dribbling was dribbling the solution on the top bars. Both were done with limited results.

Let us know how your fogger holds up. We have had this discussion before and came to the conclusion that the caustic nature of the acid would ruin the fogger.

You may want to use the powdered sugar roll instead of the alcohol to test your mite count. The normal number of bees in a test is about one cup, = 300? bees I think.

15% mite ratio is extremely high, I would be checking the sticky boards every day to get a good idea of the mite drop per day. I think you should see a high drop within two to three days if it is going to work.
http://www.beesource.com/ubb/Forum1/HTML/000799.html
http://www.beesource.com/ubb/Forum2/HTML/000468.html

Axtmann
09-20-2004, 10:57 PM
Beelord you’re to complicate with your cold fog. You can open the hive and dribbling the liquid acid in each row.

I have seen the system with the top heated method on a demonstration. It takes at least 10 minutes for each hive and doesn’t work during the cold time of the year when colonies are brood free, because bees running out of the cluster. A fan blows the acid and warm air through the hive for up to 10 minutes to reach all bees; it’s like a circulation.

With lots of colonies you can connect several Vaporizer in a line. Even if you would connect 10 or 20 together it still takes 1 minute to treat. In your situation I would call the company in your country and ask the guys.

I work with two at the same time but I know a commercial beekeeper here he runs up to 8. He has a helper to fill the trays because it vaporized faster than one guy can handle it.
The hives standing in long rows in each bee yard and he can easy treat up to 200 or more colonies in one hour.

He screwed 8 connecters on a board the same distance the hives standing together and put the board in front of the hives than plugged the vaporizer in the connecters and has a long cable with a switch close to his truck.

If you would work with 10 or 20 Vaporizer I think you need a few helper also.

Be careful with your liquid acid it’s hard on the bees because it goes in there stomach when they clean each other. When mixing the acid with water you need 35grams acid for 1000grams water (1 litre). A stronger concentration will kill bees.

swarm_trapper
09-21-2004, 05:11 AM
can a bug fogger like the fgmo fogger be use to fog the OA

Gregg
09-21-2004, 07:12 AM
Another ND beekeeper! Welcome aboard, Beelord. I have learned of another method recently to use Oxalic acid, that I may be trying soon depending on the effectiveness of the FGMO/thymol fog I just used over the weekend. Feel free to send me an email if you want to discuss this some more.

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Gregg Stewart

Michael Bush
09-21-2004, 07:37 AM
>can a bug fogger like the fgmo fogger be use to fog the OA

I assume that's what's being discussed. However I don't know of anyone doing it nor the long term effects on the fogger. My guess is the acid will corrode the fogger. Also, the fogger is made for OIL, not for water, I don't know if oxalic acid will dissolve in oil, but I would not expect that to be the case. Acids are very polar which causes them to dissolve well in water but not in oil. The Lonely "H" on the end of the acid is looking for an "OH" to be attracted to. Oil doesn't have the "OH" it's looking for. Water does.


[This message has been edited by Michael Bush (edited September 21, 2004).]

loggermike
09-21-2004, 10:08 AM
Gregg ,I hope you have better luck with the fgmo-thymol than I did.I used it this spring coming out of almonds(they picked up a lot of mites there).Mite levels kept going up.I gave up after 6 weekly treatments(fogging only).There just isnt enough thymol being delivered to have any effect ,in my opinion and I already knew the plain fgmo treatment doesnt work.The bees were sure irritated by the thymol fog ,but there was no harm done to them or the brood ,it just didnt work.
As for the COLD fogger,it might work if the acid solution doesnt destroy it,and if it can get to all the bees .To use a HOT fogger(Burgess type)one would have to find a way to mix the acid evenly with the oil, maybe with a solvent?I hear experimenting is being done in Canada with this. I dont know,but with either one breathing the vapor would be a real danger even with a respirator I think.Be Careful.

[This message has been edited by loggermike (edited September 21, 2004).]

Gregg
09-21-2004, 11:59 AM
Mike, I'm not counting on the FGMO/thymol being effective. Oxalic acid is my backup plan. I'm heading out tonight after work to do a few ether rolls to see. I did a couple of ether rolls over the weekend: 1 hive that was treated with checkmite for two weeks, had about 20 - 30 mites (not good IMO, guess I'll start believing the naysayers about coumaphos resistance, but then I had some strips left over from last year, and what else to do with them, just throw them away?); 2nd hive had no treatment since Spring (FGMO only) and, WOW, I'm estimating 80 - 100 mites (didn't bother counting them all). I was SHOCKED, I know I've got'em, but I didn't realize it was that serious. This is the hive I'm going to do another ether roll on tonight, it was fogged with FGMO/thymol on Sunday.

What are you using for Varroa this Fall?

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Gregg Stewart

loggermike
09-21-2004, 01:47 PM
Gregg,I'm throwing in Apistan strips as fast as I can get the supers off.I hadnt used them in several years so am gambling they will have an effect.A friend estimated he was getting around 75% of them with Apistan.Checkmite worked fine last year but there are a lot of mites around and I am hearing of coumophos resistance.I am planning on vaporizing oxalic in November ,sooner if the Apistan doesnt knock them back enough.

Gregg
09-21-2004, 03:03 PM
Ditto here, Mike. A friend of mine here was in salvage mode in July/August and put in Apistan then (serious mite infestation). No honey crop from these hives, but at least the bees look pretty good now. 20 - 30 mites in an ether roll that has had Checkmite in for 2 weeks sounds like resistance to me.

I'll post the number of mites from my ether roll of my test hive (FGMO/thmol fogged) here tonight or tomorrow morning. I'm curious to see if the number will have been reduced at all. Plan on checking the bottom board also if the number is significantly lower.

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Gregg Stewart

beelord
09-21-2004, 09:37 PM
I have used the Check-mite strips religiously for 4 years with great results. I used them as directed and they were removed in May of this year. I now have lots of mites so resistance is a fact for me and other beekeepers I know. We are apparently dealing with several species of mites. Some will die from Apistan, some from Check-mite, some from Tac-tic, BUT all of these treatments will fail on some mites and it is the viruses they carry that strikes terror into the hearts of beekeepers. I have seen it many times where the bees were beautiful one day and a week later they are dead or nearly so. And it usually happens right before they are supposed to go into the almonds - which is not only devastating and expensive, but really embarrasing.

I have received a reply back from the Swiss research lab and he recommends the oxalic trickling method for now. He said that it should give at least a 95% kill. One treatment only. They also have used a slow release formic acid treatment and have few mites in 8 years. My issue with formic acid is it's danger to humans and queens and it's low efficacy level.

The fogger that I bought (for $700) pushes a tiny stream of liquid and then is forced with a lot of air into a fog. I will be using it more in about 2 weeks so will report on it's durability, etc.

I am just asking "what if"?? Why not a cold fog instead of the vaporizing pan? Maybe a thermal fog is better. I just don't know. I don't have much time to spend on this experiment and I and many other beekeepers are desperate for something that is A) fast and effective B) reasonably priced C) has little or no chance for the mite to become immune to it D) does not harm the bees and E) and most importantly is organic.



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beelord
09-21-2004, 09:43 PM
Michael Bush, you are right. The bug fogger will not work for oxalic. Oxalic will dilute in water only...unless it could be diluted in emulsified vege oil???

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Axtmann
09-21-2004, 10:26 PM
Beelord how can you control the amount of oxalic acid if you blow it with lots of air into fog? What’s happening if you blow the air with pressure into a hive? If there is no gap where the pressure can escape the pressure will rise inside and kills the whole colony.
If the pressure can escape a certain amount of acid will also escape that mean it is an uncontrolled treatment.

“”I am just asking "what if"?? Why not a cold fog instead of the vaporizing pan? Maybe a thermal fog is better. I just don't know.””

The vaporizing pan is to make 100% sure each hive gets the right amount of acid to kill the mites and not the whole colony. There is no water involved and bees don’t get wet like with the trickling method. They are not cleaning each other to get dry and therefore they have no acid in their stomach.

Here are 1 gram oxalic acid tablets available to make absolutely sure the bees gets not to much acid.

swarm_trapper
09-22-2004, 05:47 AM
hey guys i read the trickleing methoud of OA application but cant seem to find it back how dose it work?

JWG
09-22-2004, 06:05 AM
Liquid oxalic acid treatment:
http://www.algonet.se/~beeman/research/oxalic/oxalic-0-nf.htm

Gregg
09-22-2004, 07:13 AM
Mike, Beelord (& anyone else interested):

Well, that does it for me concerning FGMO/thmol fogging. There were as many mites in the ether roll (maybe more) after fogging as there were before. I know this in no way constitutes a scientific study and that testing 1 hive is not a large enough group, but IMO the mite level should be at least slightly reduced after fogging, if it is effective. I was careful to have approximately the same number of bees in each ether roll.

Anybody want to buy a slightly used fogger (used only 3 times), some thymol, and a couple of bottles of FGMO?

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Gregg Stewart

loggermike
09-22-2004, 08:05 AM
>>I have received a reply back from the Swiss research lab and he recommends the oxalic trickling method for now. He said that it should give at least a 95% kill. One treatment only.

It will definitely bring down the mites that are not in the brood.But if there is still a lot of brood follow up treatments are needed and the trickling method was shown to be hard on the bees.So to be effective it needs to be done once-when the hive is mostly broodless.Your cold fogging might just be the ticket since there is no syrup used as in the trickling method.The vaporizer treatment doesnt seem to have the side effects of drizzling so repeat treatments can be carried out.Let us know how it goes-we need a fast effective way to do this.

WineMan
09-25-2004, 03:37 PM
Gregg/Loggermike

a few of us tried thymol/fgmo on around 1000 colonies this summer. kept real close track of them from time started til finished. final conclusion is that it has virtually no impact in commercial application.

in some cases it seemed to work but i think there are too many variables that make it a hit or miss proposition so i could never recommend it. i suspect the bottom line is that there is so little thymol being fanned out so fast by the bees that very little is accomplished. we kept lots of records from last year and found that with oil only the knock down rate is only about 1.5 to 2.5 times above natural fall. i believe most of the fall is due to the grooming that the bees seem to perform after the fogging and if there arent screens of some type on i suspect they get right back up cuz i never saw a higher percentage of dead ones compared to the natural fall. observed nothing different for fall when thymol is added and over the course of the summer the mite population only grew. as a whole, it never leveled off or decreased.

when failure was obvious we made the switch too. the propane method works but its darn time consuming. buddies purchased the electric model but i havent seen it used yet.

loggermike
09-25-2004, 06:39 PM
hey Wineman,Thats enough proof for me!I have solid bottoms so nothing falls through(except through the cracks).This spring it became obvious pretty fast that the mites were increasing in spite of the fgmo/thymol fogging.I would spot check around 30% of the hives with sticky boards and record the trend .It wasnt going down.The Apistan looks like it worked ,though we are gonna take a hit on the last two yards we were late in getting the supers off ,and strips in.

[This message has been edited by loggermike (edited September 25, 2004).]

Michael Bush
09-26-2004, 09:45 AM
>Well, that does it for me concerning FGMO/thmol fogging. There were as many mites in the ether roll (maybe more) after fogging as there were before. I know this in no way constitutes a scientific study and that testing 1 hive is not a large enough group, but IMO the mite level should be at least slightly reduced after fogging, if it is effective.

I think a drop test three days before and three days after treatment would be more useful and more accurate in determining what the effect on the mites is.