oxalic acid treatment

[b.lambert]

Hi
want to give my bees the trickle treatment I have two hives one on a double brood the other single can anyone give me a formulae to treat both. I have the crystals and was told 10g oxalic acid 50g sugar 250ml hot water. Is this okay and will it treat the hives in question?

[Jon]

The correct ratio is 7.5g oxalic with 100g sugar and 100ml water assuming you are using the oxalic dihydrate crystals supplied by the likes of Thorne.
It's late for oxalic treatment as bees probably have some brood by now and most of the mites will be safely tucked away.

I did a blog entry on the oxalic treatment in December here.

The standard treatment is 5ml per seam irrespective if it is a double or single brood colony.
It is not necessary to separate the two boxes in a double brood colony. Just trickle 5ml into each seam between the frames in the top box.

[gavin]

Just like to agree with Jon, although some do use a more dilute solution (and some use stronger!). That's the one I recommend, 7.5g +100g +100mls. It makes about 160ml, enough for about 5 colonies.

The lower-sugar one must be an old recipe as there is good evidence that higher sugar oxalic mixes are tolerated better.

Is it too late? No, it will do some good, but it is past the ideal time to catch all the mites in broodless colonies.

cheers

Gavin

[Rosie]

Perhaps the low sugar one was used in the days when oxalic acid was sprayed all over the bees. That was abandoned quite early in the development of oxalic acid delivery. I think it was replaced by sublimation and that, in turn, was replaced by the current safest and effective method of trickling.

Rosie

[Eric McArthur]

Rosie wrote:
Perhaps the low sugar one was used in the days when oxalic acid was sprayed all over the bees. That was abandoned quite early in the development of oxalic acid delivery. I think it was replaced by sublimation and that, in turn, was replaced by the current safest and effective method of trickling.
.................................................. ....
The definitive research on the use of oxalic acid as a trickle treatment was carried out by Charriere et al in Switzerland and reported in the Schweizerische Bienen Zeitung in October 1999. The report titled “New Recommendations for the Oxalic Acid Trickle Treatment” was reported for the first time in the English language Bee Press in the November 2000 issue, page 266, of the Scottish Beekeeper magazine.
The results of the oxalic acid trickle treatment were discussed at the International Zollikofen Congress in June 2000 and the consensus from this Congress was that an aqueous solution of 35g oxalic dihydrate dissolved a litre of 1 : 1 sugar syrup was the most suitable for the Central Europe.
The original application of oxalic acid as a spray treatment was employed in Russia by Ivanov and Sotnikov in 1988. The original oxalic acid treatment concept was pioneered in Japan byTakeuichi in 1983.
The spray treatment was perfected by Radetzki in Germany 1994. However it was very labour intensive and was quickly superseded by the Trickle Method. The Fumigation Method came later and is the most flexible if not the most popular.
I myself started using the trickle method in winter 1999 as a prophylactic and to prove to myself that the bees could survive the substance, which of course they can. I used the fumigation treatment for the first time in October 2003. That first treatment knocked down the first “fly in” Varroa incursion and using a constant monitoring system of one Varroa floor per five colonies, I have been able to keep on top of the mite from that very first incursion. Again, ask Peter Stromberg.
I moved over to the 60% formic acid treatment in 2006 and still use it today in conjunction with the trickle - as and when necessary!

Eric

[Jon]

The definitive research on the use of oxalic acid as a trickle treatment was carried out by Charriere et al in Switzerland and reported in the Schweizerische Bienen Zeitung in October 1999.
The results of the oxalic acid trickle treatment were discussed at the International Zollikofen Congress in June 2000 and the consensus from this Congress was that an aqueous solution of 35g oxalic dihydrate dissolved a litre of 1 : 1 sugar syrup was the most suitable for the Central Europe.

I think quite a lot of water has flowed under the bridge since then.

Here is another reference.

This states that 3.2% is a good strength for your average colony which is what you get with the ratio I quoted in the post above, 7.5, 100g, 100g

Nanetti seems to be the main authority on Oxalic if anyone wants to google the name.