Oxalic Acid glycerine towels, sponges, etc.

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Robert Mathews, ACBA Webmaster

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Jul 11, 2022, 8:06:30 PM7/11/22
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On the swarm list, there was a brief discussion of using Oxalic Acid and glycerine towels/sponges, which prompted someone to ask me offlist for some more info. I thought I'd post info here in the hope of sharing and getting info from people more knowledgeable and experienced than me, since I'm certainly no expert.

The Oxalic Acid glycerine theory is probably best covered on Randy Oliver's site, on this page and others:


The consensus (borne out by my small experience) seems to be that this method works well -- perhaps very well -- as a prophylactic to prevent mite counts from soaring in the first place, rather than as a treatment to lower a high mite count.

Anyway, here's what I was asked by someone, which are good questions:

>So you keep the sponges on all the time?

I personally plan to put them on in the spring and just leave them there until the fall. I don't think there's a consensus on whether they should be left on after that. In theory we might be breeding oxalic acid-resistant mites if we leave them on too much, but the scientific literature seems to indicate no trace of oxalic acid resistance yet, despite heavy use by some commercial beekeepers over periods longer than have been necessary to breed resistance to other miticides; this paper looked for evidence of resistance but didn't find it:


In practice, as Jerry suggested in the other thread, what a few hobby beekeepers do is unlikely to have much effect either way.


>I thought it wasn't approved in the US when you have honey supers on--which is most of the time here, right?

That's right, although actually, using oxalic acid on glycerin towels isn't approved at all in the US at this point. There's apparently only one legal oxalic acid product for dribble and vaporization currently, "API-Bioxal", and that was traditionally "not for use with honey supers on". However, the USDA is in the process of removing that restriction on that product:


So it seems that oxalic acid in general has been found safe for use with honey supers. Anecdotally, many people seem to have been using it that way anyway, often recommending that you put it only on the bottom brood box, then not harvesting any honey from the box above that one because it's the most likely to be affected by any oxalic acid getting in the honey. I've been harvesting honey with a one box gap from the oxalic acid towels, and it doesn't taste any different to me.

A reasonable objection is more that oxalic acid in glycerin on sponges is not authorized by the USDA for use at all as a varroa treatment. That doesn't mean anyone's found anything wrong with it; it's just that insecticides all have to be specifically authorized for use in certain ways. The Randy Oliver site goes into this and the hope is that this method will be approved eventually.

In the meantime, many people feel that if it's for their personal consumption, they're willing to bend the rules a little, and it's pretty widespread: you can actually buy the soaked shop towels at Biofuel Oasis. Everybody winks and says "this is only intended for cleaning and bleaching the wood on your hive frames". Mmmm-hmmm. I certainly wouldn't do it if I was selling honey, just because of the potential hassle if you got caught.

But for my own use, it's hard to imagine that putting the same amount of oxalic acid in a glycerin towel to be be released over several months is going to be anywhere near as harmful as using that same oxalic acid in a fogger or dribble all at once. I suppose you never know, though.

>Do you make them yourself? 25 grams of oxalic acid mixed into 25 grams of vegetable glycerin? Swedish towels?

I made them myself with the "wood bleach" oxalic acid in a plastic tub I got from Biofuel Oasis, Plus vegetable glycerin from Amazon. I did equal 1:1 weights of 500g of each. I combined it in a saucepan that I don't care about, then heated it on the barbecue to 160°F, wearing safety glasses in case of splashes, stirring gently with chopsticks. I used these sponges from Amazon recommended by Randy Oliver:


I cut them into quarters, then just stuck the sponges in the saucepan of warm solution. I didn't bother with all the complicated turning them on their side, etc. described on the Randy Oliver site; I just swirled them around with chopsticks until they absorbed the solution. Then I picked them up with the chopsticks and put them into a Ziploc bag, and they seem to be lasting well enough.

I then just put one of those quarter sponges on top of the bottom brood box and leave it there. And my mite counts in those hives are looking good.

su...@kuchinskas.com

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Jul 11, 2022, 8:55:38 PM7/11/22
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great information, thanks!

Phil Stob

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Jul 11, 2022, 9:45:06 PM7/11/22
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In one of Randy's recent articles, he pondered what exactly is the mechanism at work here.   While oxalic acid can be toxic to the mites, but the dishcloth/towel method doesn't seem to ever get to that level of toxicity. The theory, as it stands, is that the oxalic acid is interfering with their sense of smell, which makes it hard to find the right cells to dive into.  Hence, their reproduction ability is greatly reduced.   Cut their ability to reproduce by even a small amount, and they dwindle out.   That's why its not very effective with a high mite count colony, but better as a long term preventative measure.   At least that's the theory currently.   Lets see what Randy has to say next month when he comes to talk. 

Cheers, 

Robert Silverstein

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Jul 12, 2022, 1:16:04 AM7/12/22
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This past Thursday evening Randy Oliver was the speaker at the San Mateo Beekeepers’ Guild. 
His topic was Concepts in Varroa Management. My opinion is that it was a great talk and it might help others to hear from him directly. He covered topics mentioned in this thread. The recording is available on YouTube. https://youtu.be/y3fcJbK5k20
Bee well

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Jim Veitch

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Jul 12, 2022, 1:48:36 AM7/12/22
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Just to remind everyone: the ACBA is hosting an in-person workshop with Randy Oliver Saturday August 6th.  Details are below:

Tickets available  https://www.eventbrite.com/e/acba-randy-oliver-workshop-2022-tickets-371817164147

A workshop with Randy Oliver on August 6, 2022

In the morning Randy talks about how to have healthy, productive bees, about his current research and other topics of interest. The afternoon showcases how to inspect hives and what to look for.

About this event

A very popular yearly workshop by Randy Oliver has been sponsored by ACBA . Randy has been a professional beekeeper and now spends full time developing practical applications for both commercial and hobbyist beekeepers.

Attendees must be vaccinated for Covid-19 and must be members of the ACBA. Masking is expected.

The workshop is aimed at beginning to intermediate beekeepers, though in past years even very experienced beekeepers learn something. Morning lecture and afternoon hands-on demonstration so afternoon attendance is limited to 18. Cost $60 per person (eventbrite fee is extra).

Morning lecture session

The morning lecture session will start at 8:30 am sharp at San Leandro Community Center in the Thunderbolt presentation room. The morning session only is $35 and we can seat up to 50. We will be open for check-in at 8 am. Refreshments will be provided.

Afternoon session

At the lunch break, the full-day attendees will get directions to the bee yard for the afternoon hands-on session.

Lunch is on your own.

Questions and FAQ

For questions, contact Jim Veitch jvei...@gmail.com

If you don't want to pay the eventbrite fee then a check got to the Treasurer (trea...@alamedabees.org) will secure you a spot.

Find out more about Randy's advice for successful beekeeping at http://scientificbeekeeping.com/ , many of his articles have been published in the American Bee Journal.



Gerald Przybylski

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Jul 12, 2022, 4:16:21 AM7/12/22
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A quick web search turned up the links below.
Our bee forage Oxalis. Oxalis and some other forage sources have high percentages of oxalic acid
in them to fend off plant eating pests.

Mar 10, 2021 ... So, this recent ruling for oxalic acid in honey means that the FDA and USDA will not test honey for the presence of oxalic acid, or if oxalic ...

Mar 12, 2021 ... At this time, the EPA has determined that the quantity of oxalic acid (API-Bioxal™) in the honey is not expected to exceed levels that naturally ...

The following range of values were found in honeys of untreated colonies: formic acid, from 17 to 284 mg/kg, n = 34; oxalic acid, from 11 to 119 mg/kg, n = 33.

Aug 17, 2017 ... Kale, and many other foods, contains high levels of oxalate. Oxalic acid is naturally occurring and found in plants such as spinach, chard, ...

We expose ourselves to all kinds of risks. Driving, air travel (increased x-ray exposure), sun-tanning (cancer), foods, medicines, etc.
(exclude fake threats like power lines and cell phones)
It's important to know the relative threat.

Those of us who are fortunate enough not to need to treat don't have to agonize
about product residues in our honey supers or wax.

In 1988, Varroa were expanding into a "naive" population of honey bees.  Two factors accounted for Varroa population increase.
Varroa populations grew exponentially in hives in the absence of coping traits in the bee population, and
they increased more when hitchhiker are Varroa carried home by robber bees targeting Varroa weakened hives.
The survivor bees these days express Varroa resistance traits, which keep infestations in check.
The hitchhiking Varroa problem remains as long as susceptible honey bee genes remain in the neighborhood.
Genetically weak hives in the neighborhood die out, and don't reproduce.
I step down off my soapbox.
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While COVID-19 is with us, maintain social distance!
Comply with State Mandated shelter-in-place guidelines for gloves and masks.
Don't go out in public if even a little bit ill, even to catch a swarm. (Risk of spreading virus)
Swarm chasing SOLO is preferred for now.

su...@kuchinskas.com

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Jul 12, 2022, 11:38:40 AM7/12/22
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Hello! I want to combine my two weak hives. Several times, I’ve combined a swarm with an existing colony using the newspaper method, always after dark. I’ve never combined two separate colonies before.

 

These two hives are around six feet apart. Does the two feet or two miles rule apply, as in, will foragers from the eliminated hive go back to their old location?

 

Should I cheat the hive to be eliminated closer and closer to the standing hive before I combine?

 

Should I do this after dark?

 

BTW I did a sugar roll on the hive to be eliminated and only had two mites, so I don’t think this will be an issue. The standing hive is queenright but she’s not laying much.

 

Thanks!

 

Jerry Przybylski

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Jul 12, 2022, 12:17:33 PM7/12/22
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#1. Never combine a sick hive with a healthy one. 
#2.  You can pinch one of the queens, or let the bees decide. 
#3. Put the smaller colony on top of the paper over the  bigger one. 
#4. Field bees will return to the home location. Completely remove that hive and stand, or use a nuc box to collect the foragers. Keep adding them to the combined hive. Or, move the hives right next to each other before combining them. IMO the moving option will be better. 
#5. Dusk might be a little better, but any time of day is fine. Don’t work bees after dark. 

IMO. Summer is a good time for colonies to be down sized. There isn’t much foraging for them anyway. Large colonies can become robbers, and robbers bring hitchhiking mites back with them. 
Reduce entrance sizes to make hives less vulnerable to robbing. 

That’s what 2¢

-- Siri apologizes 4 autocomplete errors...

On Jul 12, 2022, at 8:38 AM, su...@kuchinskas.com wrote:


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Jennifer Radtke

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Jul 16, 2022, 12:35:17 PM7/16/22
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The BioFuel Oasis Cooperative in Berkeley sells the OA glycerin towels made by my advanced mentorship students.  This will be the 6th year in a row we are using the towels, with much success.  Basically you put them on in July, change them every 6 weeks 3x for a total of 18 weeks, which gets you through the July-October high mite season.  You need a hive to have 2 (or more) boxes of brood and put the towels between those two boxes of brood.  If only 1 box of brood, they will not work very well or enough in areas of high mites.

We have not found the sponges to be effective in Oakland/Berkeley where there is very high mite pressure, so have been continuing with the towels.  I had been worried about switching to sponges, because of the significantly lower surface area.  Randy Oliver's experiments have found that surface area matters a great deal.

My mentorship is starting an experiment starting right now with 2 hives in the same yard in Oakland/Berkeley - one with towels, one with sponges.   This time we are using 5 or below mite counts to start the hives with the treatments.   With the towels, I've recommended 8 or below as the starting mite counts, because they work quite well in our experience.  We're going to see if we start at a lower mite count with sponges, if they can work for us.

Jennifer
Jennifer Radtke, Learn from the Bees
On Monday, July 11, 2022 at 5:06:30 PM UTC-7 Robert Mathews, ACBA Webmaster wrote:

Maryly Snow

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Jul 17, 2022, 12:34:51 AM7/17/22
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Because the FDA has not yet approved Oxalic acid strips is not the same thing as saying that
the FDA does not approve of the strips!

For the past 2.5 years the FDA has been pretty busy approving Covid vaccines, especially the newer
MRNA type.

My beek and I put them on top of the bottom brood box. Haven’t noticed any taste difference.

Maryly

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su...@kuchinskas.com

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Sep 6, 2022, 6:59:42 PM9/6/22
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I have a Mann Lake plastic, hand-cranked two-frame extractor I’m ready to pass along. The crank handle has broken, but you can order a new one for $7.50.

 

This is the extractor: https://www.mannlakeltd.com/beekeeping/extraction-bottling/honey-extraction/extractors/2-frame-plastic-extractor/

 

The part number for the handle is HH131.

 

It just doesn’t work for me: It’s quite deep, and with the limited amount of honey I’m getting these days—every drop is precious--it’s too difficult to get it all out.

 

You can pick it up in the EC hills. If you respond, let me know when you could pick it up. I’d rather give it to the first person who can come, rather than the first person who hits respond.

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su...@kuchinskas.com

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Sep 7, 2022, 4:00:24 PM9/7/22
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The extractor is spoken for!

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