Oxalic Acid now - pros / cons?

[ksjs]

For whatever reason I seemed to have concluded that OA treatment was excessive and unnecessary if you had used Apiguard in the autumn. This wasn't based on anything other than assumption; not good enough.

Anyway, I've recently become aware of the fact that this runs contrary to what most people do in terms of proper varroa management (though as ever it seems there's debate on this). I understand OA should be applied in Dec / Jan i.e. 'broodless' periods. Therefore late Feb is late for treatment! I know however OA can be applied any time though is less effective when brood is present.

I will do more reading around the subject but in the interim can someone give a guide as to best course of action / does anyone know of a source that gives an overview of whether it might be best to leave things as they are or to go ahead with treatment given circumstances.

By the way, this is just 1 hive, was treated with Apiguard in autumn and it had zero mite drop during last days of the treatment. The hive seems OK at the moment with the occasional day out for the ladies over the last month or so, a constant gentle buzz and, from hefting, still a decent amount of stores left. Strong winds, wet and cold here for now.

Thanks for any help.

 

[BBG]

This will create some debate.

Weather has said that Feb and March will be warmer than usual while April and May will be colder than usual (for those months). I think they're right.

Oxalic does some disgusting stuff and there are long time beekeepers who don't use it at all - others do.

 

[mbc]

pros = kill some varroa
cons = kill some open brood, possibly shorten lifespan of workers, interfering with the bees when they're best left alone

 

[Finman]

.
It is now end of February. Propably beehives in Britain have quite much capped brood. Mites are in safe under cappings. Oxalic does not work in this situation.

If you have several hives, you may lift the brood frames to the biggest hive. Then you may clean broodless hives with oxalic.

That brood hive you may clean with thymol or with formic acid later when days are 15C warm.

 

[Finman]

Oxalic does some disgusting stuff and there are long time beekeepers who don't use it at all - others do.

in Denmark every beekeeper uses trickling. It is absolutely the best treatment ever invented if the hive has brood brake.

We here in Finland are adding Spring treatment but it is very different that of UK.

At once after cleansing flight trickling may be used. We have then half metre snow and Winter continues. If lucky, the hive has not yet brood and oxalic do its job.

.

 

[itma]

Most of the varroa live in capped brood cells.

Oxalic only hits varroa that are on bees, not protected in sealed cells.

So Oxalic is used when the mites have nowhere to hide - when the bees are broodless.

It makes no sense to use it when there is brood present.




Do you have a current varroa problem?
If not, relax.
What does your inspection board show after several (count them) days?
Be concerned if there's more than 10/day (averaged over those several days) at any time of the year, but that doesn't need to mean Oxalic. Though of course a swarm, natural or artificial, doesn't have any brood ...

 

[jenkinsbrynmair]

If you're that concerned, wait until it warms a bit and Apiguard before serious nectar flow starts

 

[susbees]

Be concerned if there's more than 10/day (averaged over those several days) at any time of the year, but that doesn't need to mean Oxalic. Though of course a swarm, natural or artificial, doesn't have any brood ...

Most of us can assume a long brooding season this year I'd think: 10 mites a day averaged over 10 days in February natural drop....equals an early shook swarm with estimates of 500-4000 mites in the colony. I would be "concerned".

 

[Easy Beesy]

ksjs
why have you changed your mind? why do you want to treat? have you done a mite count? is it high enough to warrent treatment? if not, why worry about it now? leave it til you AS your colony. OA is not compulsory.

Eb

 

[Queens59]

Year 1 - Didn't like the 'idea' of OA so didn't use it, just used Apiguard and another Apivar (or sim) treatment in early season.

Bees spent most of year 2 killing every Queen and producing nothing

This winter? Used OA and will top up this thread in autumn/winter 2012 as to how they manage this year...

 

[Monsieur Abeille]

As per itma - dont fret unless you know you have a serious mite problem. Put a monitor board in and count the mites after a week or so. If a large amount then consider your next option - possibly apiguard/api life var, possibly a shook swarm - when its warmer.

Dont beat yourself up too much, many disagree with the use of Oxalic at all. In any event, now is not the time to consider using it without proof of a large infestation (and probably not even then).

 

[oliver90owner]

Personally, I don't like Apiguard (Thymol) because of the 'going off-lay' problem at the most prolific laying time of the year. And it is likely not that good anyway, efficacy-wise.

Probably prefer a shook swarm, with first capped brood culled after it, as a preferred attack in spring.

No chemicals, there are other benefits and it is effective (with the first capped brood culling). With several colonies, I do admit to not losing all the brood I take from them, but that is another story.

RAB

 

[tkwinston4]

I do admit to not losing all the brood I take from them, but that is another story.

RAB

Tell??

 

[Hivemaker.]

Tell??

Transfer it to other colonys until emerged.

 

[ksjs]

Do you have a current varroa problem?
If not, relax.
What does your inspection board show after several (count them) days?
Be concerned if there's more than 10/day (averaged over those several days) at any time of the year, but that doesn't need to mean Oxalic.

Doesn't everyone have a varroa problem?
As mentioned above I had zero mite fall during last few days of apiguard in autumn, what this means right now I don't know. I have no varroa floor in at moment to help ventilation. Could put in then count after a few days.

 

[ksjs]

ksjs
why have you changed your mind? why do you want to treat? have you done a mite count? is it high enough to warrent treatment? if not, why worry about it now? leave it til you AS your colony. OA is not compulsory.
Eb

Doing a bee course at moment and last class was on diseases: the explicit advice given was apiguard in autumn OA in Jan without exception. I hadn't been aware that this treatment regime was so 'approved'. I appreciate it probably isn't as there are some dissenting voices.

I want to treat to give bees best chance. This is not based on any count though (nor indeed a good enough understanding of OA and varroa / other forms of control e.g. culling drone) which is probably next step.

 

[ksjs]

Personally, I don't like Apiguard (Thymol) because of the 'going off-lay' problem at the most prolific laying time of the year. And it is likely not that good anyway, efficacy-wise.

Isn't it around 90 something % effective? Surely that, along with other measures, makes apiguard an important part of managing varroa? As for going off-lay, do you reckon there's insufficient time following apiguard for queen to get back into laying such that there's sufficient winter bees?

 

[ksjs]

Dont beat yourself up too much, many disagree with the use of Oxalic at all. In any event, now is not the time to consider using it without proof of a large infestation (and probably not even then).

Thanks for this and all other replies - varroa board going in now. Will see what count is and take it from there.

Utter ming in N Wales today: hive is sodden and my wind break (garden wind break netting) which is stretched over the hive and held down by concrete blocks was virtually off this morning. Hope they aren't too annoyed...

 

[oliver90owner]

the explicit advice given was apiguard in autumn OA in Jan without exception (my undelining)

Sounds more like instructions to me. Was it Finman delivering the course?

In my opinion it is utter clap-trap. Advice and direct instructions are somewhat different.

Not used Apiguard in autumn nor oxalic in January for the last five years, or more. Can't be more explicit than that. Sounds more like instructions for dummies than learning to become a beekeeper. From dummies, as well? There may be a case of students only hearing what they want to hear, I don't know. Need to hear both sides, but there is something amiss with your course, I would suggest.

RAB

 

[oliver90owner]

Isn't it around 90 something % effective?

Is it? Never yet seen any average values for efficacy under typical UK conditions. Best to find the minimums so you know the possible range, as well. Being over-optimistic can be very bad for the bees.

do you reckon there's insufficient time following apiguard for queen to get back into laying such that there's sufficient winter bees?

Sorry, the post had nothing to do with the above, I was responding to post #11. Extra thoughts from then were about the actual strength of the colony - this needs to be included before blindly jumping in with any arbitrary treatments/manipulations.

RAB