oxalic acid and glycerine mix

[Hivemaker.]

We are using an active, rather than a passive, vaporizer and find it works extremely well. Perhaps these 12v pan type ones don't really deliver the goods

Never used one of the pan type passive vaporizers so cannot comment much on those, but treating from the top with a pressurized type works very effectively.

 

[Beefriendly]

This is the research from Argentina using celulose/cardboard.

http://link.springer.com/article/10.1007/s13592-015-0405-7#Tab3

Here is a discussion using celulose/cardboard.

Please correct me if I'm wrong, but are you saying they used something like gun cotton to soak the oxalic/glycerine mixture into?

My mistake, we used a lot of nitrocellulose membranes in the lab for Northern/southern/western blotting of DNA and RNA.
The stuff we used wasn't dangerous LOL........http://www.gelifesciences.com/webap...0101&productId=&top=Y&storeId=12751&langId=-1
I just mis-remembered cellulose strips as nitrocellulose strips because I'm more familiar with them.

 

[Hivemaker.]

Update on RO website.

Update 24 Jan 2017

There has been lots of response to my article on OA/gly in ABJ (soon to be posted to this website). I’m in communication with EPA to get this application method approved.

I’m in the middle of a trial of OA/gly shop towels on 6 hives during our wet, cold winter. As of today, after ~3 weeks, the colonies are not showing any adverse effects upon the bees.

I’m currently working on is the best ratio of OA to glycerin, and the best amount per towel. The problem is that the towels don’t want to evenly absorb the optimum amount of glycerin to leave them less “oily” so that the bees will chew at the towels. I’m trying to figure out how to get a full roll of towels to absorb the right amount of solution without the need for squeezing out the excess.

I tried 700g OA in 700ml of glycerin, heated to 160F, and the roll of towels preheated 1.5 minutes in the microwave. I poured the hot solution into a tall, narrow asparagus pot, and set one end of the towel roll into the pot. When the solution had soaked half way up, I flipped the roll over, and placed the roll into a warm oven. After 15 minutes, the solution has still not absorbed to the center of the roll. So I left it for another hour in the warm oven. This proved to be a mistake, since the acid degraded the lower part of the roll into a soft mess.

The 700ml of glycerin also appeared to be too much–leaving the towels too “oily” feeling.

I’m now going to experiment with adding isopropyl alcohol (boiling point 180F) to the solution, and decreasing the amount of glycerin.

Please email me if you figure out ways to improve the method, and I’ll post here.

http://scientificbeekeeping.com/oxalic-dribble-tips/

 

[Finman]

.
Here is one study about glyserol and oxalic acid from year 2000
http://www.apidologie.org/articles/apido/pdf/2001/02/milani.pdf

Abstract
The toxicity of oxalic and citric acid to Varroa destructor was studied with a laboratory assay. A contact test was used for the bioassay.

Capsules were sprayed with solutions of the acids in a Potter tower and allowed to dry. Slight but significant differences in toxicity of oxalic acid were found among mites from different brood stages;

the median lethal density for mites from pupae with white eyes was 1.49 $\mu$g/cm2.

- Citric acid was less toxic than oxalic acid.

- The addition of sucrose to oxalic acid made the material more hygroscopic and the mortality of the mites increased at 75% R.H.

- Glycerol showed a similar synergic activity irrespective of relative humidity.

.Continued

Ten to 15 female Varroa destructor were
introduced into each capsule; after 4 h they
were transferred into a clean glass Petri dish
(60 mm dia.) with two or three worker larvae
taken from cells 0–24 h after capping
(Milani, 1995). To avoid the transfer of acid
crystals into the Petri dish, mites were first
transferred with a fine brush into a polystyrene
dish – without touching the treated
surface – and immediately after into the
glass Petri dish. The mites were observed
under a dissecting microscope 4 h (when
transferring into the Petri dish), 24 and 48 h
after the beginning of the treatment and classified
as mobile, paralysed or dead as in
Milani (1995).

So, there were no bees with mites!

- The mortality in treated capsules indicates
that oxalic acid and citric acid have a
contact toxicity on V. destructor, without
excluding other ways of action.

- Sucrose and glycerol proved to be synergists
of oxalic acid – at suitable concentrations
– under laboratory conditions.

- These results indicate that the efficacy
of a treatment with oxalic acid mixed
with sucrose and its side effects on bees,
although independent of temperature, might
be influenced by relative humidity.

 

[Hivemaker.]

Oxalic and glycerine strips.

http://scientificbeekeeping.com/scibeeimages/2016-Beyond-Taktic-pdf.pdf

 

[Finman]

Oxalic and glycerine strips.

http://scientificbeekeeping.com/scibeeimages/2016-Beyond-Taktic-pdf.pdf

Well. A huge work and quick release of results. Normal university research takes 5 years: Planning, funding, 3 years field working, writing and accept process...

 

[mbc]

Oxalic and glycerine strips.

http://scientificbeekeeping.com/scibeeimages/2016-Beyond-Taktic-pdf.pdf

Rubbish, this guys not been in the European varroa group for 20 years, can't be useful.

Seriously, thanks for posting

 

[charlievictorbravo]

Oxalic and glycerine strips.

http://scientificbeekeeping.com/scibeeimages/2016-Beyond-Taktic-pdf.pdf

Thanks for posting that link - the .pdf is much easier to read than the pages from the ABJ and the tables and illustrations are clearer too.

Who's going to test it here (temperate atlantic maritime climate, rather than California) first? - using Api-Bioxal of course! You'd still be a scofflaw but to a lesser extent (using an approved chemical in a non-approved manner).

CVB

 

[Finman]

.
Los Angeles is situated at same latitude as Morocco's Rabat, 34 degree. Maritime climate.

Their climate is a good benchmark to Milton Keynes beekeeping.
.

Los Angeles has just now 20-25C day temps. At night 10C.

.

 

[piggy]

Does anybody know if a J-cloth would be similar to shop towel?

 

[charlievictorbravo]

Does anybody know if a J-cloth would be similar to shop towel?

Possibly too much fabric in J-cloths. Scott's Shop Towels are available in the UK - http://www.halfords.com/motoring/car-cleaning/sponges-brushes-buckets/scott-garage-shop-towels

You thinking of giving it a whizz?

CVB

 

[Erichalfbee]

Scott's Shop Towels are available in the UK -
You thinking of giving it a whizz?

CVB

Nick them from motorway service station loos?

 

[piggy]

I might give it a try in August, if there is a little more info. going forward.

It looks very promising, has anybody tried it in UK.

 

[JWF]

Looks interesting, definitely a good fit for end of season treatment after the supers are off.

 

[charlievictorbravo]

I might give it a try in August, if there is a little more info. going forward.

It looks very promising, has anybody tried it in UK.

I doubt it's been tried here. The blue towel idea has only just been made public by Randy Oliver and the forerunner of that was the idea of using cardboard strips soaked in the glycerin/OA mixture, which came from Argentina - they're actually on sale there as Aluen CAP. I hadn't heard of Aluen CAP before I read the RO article a week ago.

Whereabouts in Devon are you - I might be able to give you a hand with the assembly of the treatment.

CVB

 

[charlievictorbravo]

Nick them from motorway service station loos?

We don't have any of those new-fangled motorways down here, my lovely. Nearest MSA is over 2 hours away from here. You've probably got lots of them in Ceredigion. Send me some towels, will you, next time you nick some.

CVB

 

[Hivemaker.]

Reading about the results and looking at the charts I was rather impressed by the cardboard strips, a good cardboard which should be suitable for this can be obtained in large sheets from a company that produces the plain board used to make into beer mats, if a lot was to be required at a good price.

 

[charlievictorbravo]

Reading about the results and looking at the charts I was rather impressed by the cardboard strips, a good cardboard which should be suitable for this can be obtained in large sheets from a company that produces the plain board used to make into beer mats, if a lot was to be required at a good price.

The strips were better for a small operation but RO was concerned about the labour involved in making , fitting, removing and disposing of the strips arising from his 1500 double-box hives - 12,000 strips involved!

I can see how the towels might work - bees chew them and drag the chewings out through the front door, spreading OA crystals around the hive on the way. The photos of the strips did not show much sign of being chewed at all, so my question is how does it work (getting the OA in contact with the mites)? Notwithstanding that we don't know HOW they work, RO's results show the strips were marginally better than his shop towels.

CVB

 

[Hivemaker.]

The strips were better for a small operation but RO was concerned about the labour involved in making , fitting, removing and disposing of the strips arising from his 1500 double-box hives - 12,000 strips involved!

According to Fernando, one of the guys to do with the development of the cardboard strips, and one who is named by Randy as giving him advice...
he has this to say about the cardboard strips.....

The bees begin to gnaw the strips until they are removed from the hive. Then if population and brood is high the bees will removed the strips in less than two month.

But even if they didn't remove the strips I see it as no big problem, no more so than the plastic strips that need to be suspended between the frames like Apivar, Bayvarol, Apistan,etc... the bees certainly don't remove these and they have been used for years, and still are, by beekeepers with just a few hives up to those beekeepers running thousands of hives, with no big issue, and those plastic strips also have to be disposed of.
I also like the fact that the strips are actually suspended in the bee ways, near the brood, so the bees cannot easily avoid them.

The shop towels may or may not present another problem if used in late summer and during the autumn, one being they may hinder any feeding, especially if using contact feeders, and could be ignored by any bees prone to having a smaller nest with a large honey arc above.

 

[foghornleghorn]

Looks interesting, definitely a good fit for end of season treatment after the supers are off.

Assuming its wouldn't be strong enough on its own for a single yearly application what would the best way to combine it with thymol/maqs etc?