winter oxalic treatment

[Hawklord]

Is there an optimum time ie weather, when the OA should be done? I'm thinking about heat loss from the colony while the treatment is being administered.

 

[jimbeekeeper]

I'm thinking about heat loss from the colony while the treatment is being administered.

Heat loss should not be an issue with OA trickle addtion due to the time the opperation takes which should be less than 60 seconds.

But as others have susgested, the OA solution should be about 20-25 deg C

 

[Finman]

Is there an optimum time ie weather, when the OA should be done? I'm thinking about heat loss from the colony while the treatment is being administered.

When bees are disturbed, they rise they temp to 30-40 C fronm 23c.

You must keep hurry before the temp rises. Bee cluster expands and it is difficult to put inned cover back.

Don't worry about heat loss.

Good handling temp is -5C - +5C. In higher temperature bees often try to attack and you need smoke.

 

[m100]

The rise in temperature isn't just the expansion of the cluster, it decreases the life of the bees. So as little disturbance as possible is the best bet. This means, everything is prepared and ready to go before you lift the lid, no splitting of supers from brood and a half, or splitting of double brood boxes, and quick effective tricking of 5ml per seam evenly spread all along any occupied seam.

Observe bees, trickle, move to next seam, observe bees trickle and so on. If it drops directly out of the hive onto the floor then it simply doesn't matter. Oxalic acid is cheap. With a 50ml syringe an effective but not excessive dose is achieved very quickly this way, squeeze to the next graduation mark, then stop.

You refill the syringe to 50ml for the next hive and you're all set to go again without mucking about worrying about what mark you were up to last or refilling halfway through. Of course if you have more than 10 seams of bees in your hive then you are buggered, but then you really shouldn't have clusters that big now

Pissing about with '3.5ml' over just the bees in a seam as some have suggested (here?) or in some of the mags is IMHO a waste of time.

 

[plumber]

bit of an ***** so I am asking how oxalic acid works.

is it absorbed by the varroa
is it coated on the bees and absorbed by the varroa
are parts of the parasite distroyed by the acid
what is the train of events ie trickle ???????? mite death
what happens in between
you trickle because it works but why
some vaporise it works but why
I have read papers they say do this at this time it will
reduce your mite load but often do not say why.

off to the anderson shelter

 

[BEEBEGIN]

Hi
So I have gone back to all this discussion that was happening in 2008.It looks to me that this oxalic treatment is best done when it is really cold like it has been the past month.
I should have read before deciding.
Will it matter do you think that the temp has now got up a bit?
Or do you think I should wait till cold is upon us again?

 

[gavin]

A lot of people - me included - have assumed that cold weather at this time of year suppresses brood production. That might be right, but I don't think anyone really knows. As mites jump into cells around 8-9 days after the egg is laid (just before sealing), there would be a delay after egg laying starts before the mites hide in sealed cells. So now is a very good time. A further consideration is that the bees will soon be on a mission to raise new brood whatever the conditions outside, so don't delay and give the treatment asap.

hope that helps

Gavin

 

[Finman]

Pissing about with '3.5ml' over just the bees in a seam as some have suggested (here?) or in some of the mags is IMHO a waste of time.

When EU varroa group developed this trickling system "per seam" was a new invention. Before that the syrup was only pissed on bees and the results become better with seam-system.

Actually bees are in "seam slices". It is not homogenous ball like we often think. If the weather is cold, bees stay in their seams and shrinken together.

 

[Onge]

LOL loved the term p155ed.

I'm sure it's a translation thing but it did make me chuckle.

Or is it the Leffe I'm drinking.

 

[Meg]

Plumber,

The acid attacks the mites feet - sticky pads, and their mouthparts so they cannot hang onto the bees properly or feed.

Applied in the middle of winter as most varroa are then 'phoretic' i.e. on the adult bees where they can be got at by the acid and not hidden beneath brood cappings.

Acid is applied in syrup so that is sticks to the bees and they want to try and groom it off. This spreadss it arouond and gives contact with a greater number of mites.

Most mites are killed within a few days.

Meg

 

[BEEBEGIN]

Ox acid

Well gave them it today,quite worm so as soon as I opened up out they came to see what was going on.
One hive (larger one of them all) di not mind at all.My smaller hive,as soon as I started to openup out they came and did not think much of it.
Any way the job is done and hopefully it will work.
Next stop Spring feeding.
PS
I must admit that before the snow came to us and we had a few 10 deg days(well about one hour) then crash back down to minus 1 or2.Any way there were a few bees that came out to have a look around,but by the time the sun was in and out quite a fe did not make it.

 

[Skyhook]

Am I glad I did that! After getting down to a count of zero with September treatment, I wasn't going to OA, but then relented. Having treated yesterday, today there were exactly 100 mites on the board!

I will post the results when they've finished dropping.

 

[Finman]

Am I glad I did that! After getting down to a count of zero with September treatment, I wasn't going to OA, but then relented. Having treated yesterday, today there were exactly 100 mites on the board!

I will post the results when they've finished dropping.

the biggest part of mites will die during 2 weeks .

It takes 4 weeks to drop.

 

[Meg]

Depends on whether colony is truly broodless or not. Phoretic mites (on the adult bees) should all be affected and therefore drop within a couple of days.

Meg

 

[peterbees]

For useful info on using Oxalic Acid, see Wally Shaw's piece on the Welsh BKA website Information Station item 001 www.wbka.com

 

[Finman]

Depends on whether colony is truly broodless or not. Phoretic mites (on the adult bees) should all be affected and therefore drop within a couple of days.

Meg

In broodless hive mites will drop during 4 weeks. I know that.
In couple of days they drop only few.

 

[MJBee]

Finman,

IF the colony is broodless why does the OA not act on the vareroa almost immediately? Four weeks seems to be a long time for it to take effect.

Regards Mike

 

[Erichalfbee]

I read that oxalic damages the mites claspers so that they cannot suck haemolymph so perhaps they drop off when they themselves are starving?
There is also damage to the respiratory system so perhaps the latter accounts for the immediate drop and the former for the later drop?

 

[Finman]

Finman,

IF the colony is broodless why does the OA not act on the vareroa almost immediately? Four weeks seems to be a long time for it to take effect.

Regards Mike

i do not know but so it happens. See Dave Cushman graphs.
Our varroa experts have statistics too.

 

[Finman]

the delay after treatment of the mite fall with different winter treatments

http://www.dave-cushman.net/bee/oxalic.html

Perizin is used 20 years ago and it is still in use to compare efficacy.

Perizin is Coumaphos compound. It is a non-volatile, fat-soluble thiophosphate ester with ectoparasiticide properties: it kills insects and mites. It is well known under manufacturer brand-names as a dip or wash, used on farm and domestic animals to control ticks, mites, flies and fleas. [1]

Like you see, it does not kill all mitea at once.