oxalic acid strength

[gavin]

No probs MM - but I wanted to post the original here as I was trying to be as clear as I could and I think that the 'other place' post was clear as it was. In general, just lifting something straight out of one forum and into another (as I did this morning) isn't right, but as I wrote the thing I thought that would be OK.

Didn't know that Rothamstead were also playing with oxalic acid solutions, but I suppose every bee researcher would have thought about it then.



Gavin

 

[Finman]

By calling the 7.5+100+100 recipe as 3.5% once again you are confusing people. Please, please, please more!

Gavin

Thanks Gavin. I have seen yours math skills.

 

[jimbeekeeper]

yawn!

 

[Bee-Key-Pur]

No, not yawn, can we have more, it's better than eastenders!!!

Brian

 

[dickbowyer]

Still confused, is the P*****/M******* supplied Italian 6% solution of OA in sugar solution OK or not to use straight out of the bottle in good old blighty? If efficacy is better with higher "strength" solutions, are the colonies more damaged?

 

[jimbeekeeper]

Still confused, is the P*****/M******* supplied Italian 6% solution of OA in sugar solution OK or not to use straight out of the bottle in good old blighty? If efficacy is better with higher "strength" solutions, are the colonies more damaged?

Why not contact the maker?

 

[drstitson]

italians seem to have same problem with recipes for OA!

BUT

6% would appear to be the concentration recommended by italian academics so that's obviously why it is supplied as that for neat use at 5ml per seam:

"Sono stato alla fiera del miele a Montalcino dove vi era uno stand di una rivista di apicoltura nuova; nella quale è riportato un articolo del Dott. Nanetti [CRA-API] in merito all'uso dell' ossalico con la tecnica del gocciolamento "efficace, semplice, economico, sicuro per l'uomo, tollerato dalle api e rispettoso dei prodotti delle api" nella formula dei 100 grammi di acido ossalico, 1000 di zucchero, 1000 di acqua e cinque millimetri per favo occupato dalle api"

 

[Finman]

italians seem to have same problem with recipes for OA!

"efficace, semplice, economico, sicuro per l'uomo, tollerato dalle api e rispettoso dei prodotti delle api" nella formula dei 100 grammi di acido ossalico, 1000 di zucchero, 1000 di acqua e cinque millimetri per favo occupato dalle api"

..........100/ 2100 = 4,8%


-............................the difference with 6 and 4,8 is that 6 is 25% bigger than 4,8

 

[drstitson]

No no no

"100/ 2100 = 4,8%"

NO NO NO - that is w/w not w/v

doesn't anyone pay attention when making winter syrup????


1kg sugar + 1 kg water = around 1.6 litres solution NOT 2 litres ( ie less than a full pop bottle).

so 100g oxalic (which adds say another 50ml to final volume) is 6% w/v

 

[Hombre]

Doubtless this will rattle on like this again at the end of the year, then someone in Continental Europe will suggest that things should be harmonised, allowing the discussion to be renewed for another three or four years. As we discuss an interim figure uncommon to both ConEu and UK alike.

That will doubtless impress Finman and others no-end.

 

[Finman]

.
IF YOU KNOW SOMETHING ABOUT CHEMIST, THE PERCENTAGE WILL BE CALCULATED WITH WEIGHTS

The formula is

7,5 G + 100 G SUGAR + 100 G WATER = 207,5 G

7,5/207,5 = 3,6%


you need not know anything about volume. You may report the alcohol with voloume percent of with weight percent, but in this trickling case it means weight % all the time.

Listen guys. I have not invented these formulas and they are made by European Union Varroa Group. A Finnish group member Seppo Korpela invented for exacple the " 5 ml by seam". It was better than just sprayieng on bees.

 

[gavin]

Phew! Thanks Drstitson. And personally I think that the harmonisation is there: 4.5% (3.2) or 3.5% (2.5), take your pick. I don't think that anyone in the UK should be selling Italian 6%, and if folk don't stray off into half-baked variants due to misunderstandings then life would be a lot simpler. However ...

Still confused, is the P*****/M******* supplied Italian 6% solution of OA in sugar solution OK or not to use straight out of the bottle in good old blighty? If efficacy is better with higher "strength" solutions, are the colonies more damaged?

The easily bored are free to look away now.

Dick and anyone else still worried about the Endolapi pre-made oxalic acid solution: yes, colonies may be more damaged with higher doses, but probably much of the time you will not see it.

a) 6% (w/v) oxalic acid dihydrate - Endolapi from Pa****s and Maisemore
b) 4.5% (w/v) (aka 3.2% anhydrous) - Trickle 2 from Thornes
c) 3.5% (w/v) (aka 2.5%) - some folk and - apparently - Oxuvar

As you go down the list you decrease the risk to your bees without compromising (much) the effect on Varroa. Pa***es told a list member that their one (a) was approved by an English regional bee inspector yet most in N Europe think it too strong. So if you use it things will probably be OK. However ... it would be safer to dilute it. Full marks to Sabrina who used light syrup to dilute it. If you want to know how much sugar and water to add to the Endolapi 6% stuff to convert it to the 4.5%/3.2% strength then it was posted here: http://www.beekeepingforum.co.uk/showpost.php?p=99946&postcount=4

Hope that helps - hope it didn't make too many people yawn - hope that it was as good as Eastenders - and I hope that Finman has more of an interest now in lemon juice (v/v!) and can leave this one alone

Gavin

 

[gavin]

.
...... but in this trickling case it means weight % all the time.

Sheesh!!!! Help ma boab .......

.... but all the packaging on the commercial stuff, all the recipes given out by reputable organisations and the scientific papers say 'w/v' .....

 

[Finman]

"100/ 2100 = 4,8%"

NO NO NO - that is w/w not w/v

doesn't anyone pay attention when making winter syrup????

1 kg water + 1 kg sugar = 2 kg syrup = 50% sugar


If you calculate 1 kg sugar /1,6 syrup = 63% sugar (false) Then you calculate water content 1 kg water /1,6 syrup = 63% water


So we have both water and sugar 63%. Is that correct?. together = 126%

 

[Finman]

Sheesh!!!! Help ma boab .......

.... but all the packaging on the commercial stuff, all the recipes given out by reputable organisations and the scientific papers say 'w/v' .....

Tell me where? What are those your reputable organisations?

 

[Finman]

.... all the recipes given out by reputable organisations and the scientific papers say 'w/v' .....

Here is yours British Beekeepers Association Advisory Leaflet Number B13
BBKA 2007
Obtaining the oxalic acid


Because the concentration is very critical
the BBKA advice is to obtain a PREPARED
SOLUTION of Oxalic Acid in sugar.

There are some available on the market from bee
suppliers such as:
Oxalic Acid from Endolapi SRL (Italy) which
is 6% of oxalic acid in a 30% sugar solution
Oxuvar from Andermatt. Which is a 3%
solution of oxalic acid supplied with sugar
to make up the desired concentration.......The dosage required is 5 ml
(millilitres) per seam of bees. This can be achieved by counting the
number of seams where there are significant numbers of bees.
Multiply this figure by 5 and this will give the quantity in ml of oxalic
acid solution that should be applied to the colony.


Guys, can you explain what that bolded text means. It is copied from BBKA link.

 

[Finman]

.
Is there comma in wrong place.
There are two products

1) Italian Endolapi SRL 6%

2) German Oxuvar from Andermatt, which is a 3%


What does mean "Mit OXUVAR® wird eine Oxalsäuredihydrat-Lösung 3.5 % zum Träufeln verfügbar gemacht, die sich speziell durch ihre einfache Applikation auszeichnet." http://vimeo.com/4560147

where it is said W/v in official text?

 

[Finman]

How do you explain this:

The treatment material is 3.2% oxalic acid in a 1:1 sugar solution.

The recipe for making this is as follows:- Make up a sugar syrup consisting of 1 kg sugar in 1 L of water. To this should be added 75 gm of oxalic acid dihydrate and well mixed. This will make 1.67 L of treatment material. Accurate weighing of the oxalic acid is essential because under-strength will give a poor mite kill and over-strength may kill bees!

http://www.dave-cushman.net/bee/wallyshaw.html
Wally Shaw's Oxalic Acid Trickling Document For Varroa Treatment

The trickling method was invented by professor Nanetti from Italy.

It was tested and developed further in European Union Varroa Group


.

 

[gavin]

Tell me where? What are those your reputable organisations?

Let's start (and, I hope, finish) with two:

The Welsh Beekeepers Association: http://www.wbka.com/infostation.html

The New Zealand Ministry of Agriculture and Forestry:

http://homepage.ntlworld.com/gandboss/BeeginnersFAQ/Problems/control-of-varroa-guide.pdf

That last guide is an excellent handbook. Look in the Appendix for the details.

 

[Finman]

Let's start (and, I hope, finish) with two:

The Welsh Beekeepers Association: http://www.wbka.com/infostation.html

The New Zealand Ministry of Agriculture and Forestry:

http://homepage.ntlworld.com/gandboss/BeeginnersFAQ/Problems/control-of-varroa-guide.pdf

That last guide in an excellent handbook. Look in the Appendix for the details.

Why don't you use European original reseaches and experts which have revieled this handling system?

You you know any famous varroa researcher in European country?

I have read the NZ handbook before you. It is collected from litterature and there is many faults inside.

.