Oxalic acid treatment

[BKF Admin]

Have you used an Oxalic acid treatment this winter?

 

[MJBee]

When I saw the poll I thought - only 12 votes not a very good response - then I noted it had only been running for 27 minutes!! - good response keep 'em coming.

A further thought how about adding first 24 hours mite drop figures - this would let members have some idea how their colonies are faring.
All the best for 2009
Mike

 

[Polyanwood]

I didn't manage to do 24 hour drop, but I got 28 mites in the 8 days after treatment. Perhaps the thymol has already killed most of them? Or perhaps there is a positive correlation between them being super defensive bees and being super hygienic!!! Ha, ha, Ha... if only.

 

[jimbeekeeper]

A further thought how about adding first 24 hours mite drop figures - this would let members have some idea how their colonies are faring.

Mike

Thats a good idea Mike, because when I did mine and got the following results I was quite shocked. On asking the question on this forum it turns out the drop is quite low.

Here are my results

- pre Oxalic treatment ave <1 day
- 24 hrs after OA - ~ 200
- 48 hrs after OA ~ 50
-96 hrs after OA <10

 

[MJBee]

Watch this space 2 hours to go to first 24
Mike

 

[MJBee]

I looks like the blitz I had on Varroa this year has paid dividends:-

24 hour post oxalic drop - 4 colonies - Best 0, Worst 25

Monitored since mid August total mites removed Best 337 Worst 1743

Next count will be a 7 day average.

Regards Mike

 

[tony350i]

no treatments off any kind for me this year.

Regards Tony

 

[BKF Admin]

Tony how is the small cell project going?

 

[tony350i]

hello Admin i hope this site and you have a good new year.

In winter i all ways leave fondant and pollen sub on all my hives and a couple days ago i gave some hives a top up but not all needed it.

They all look good to me i don't know what to say, all the hives that i regressed have all drawn 4.9mm foundation to a good standard and the only treatment that they got last year was one trickle at Christmas so i feel happy about letting them stand on there own, as long as i don't let them go hungry i think they will do ok.

thanks for asking

regards Tony

 

[bobandbec]

Checked one of my colonies after 3 days and counted a mite drop of 12. Hopefully the Apiguard in September worked! Begs the question whether Oxalic is essential after an Autumn treatment has been used?

Peter

 

[Polyanwood]

I wondered the same Peter because my mite drop was so low.

The question is at what level of mites is the harm of oxalic acid treatment greater than the likely harm of allowing mites to remain untreated? Is this question answered in the Defra book on varroa?

 

[ian]

Hi all

The only good mite is a dead one

I would not expect huge drops unless you have had problems/poor results from Autumn treatments. Good Autumn treatments are essential in protecting your winter bees

The benifit of Oxalic will be felt the following season when even a dozen mites now will amount to 1000s. It just gives you as clean a start as you can get.


Regards Ian

 

[BKF Admin]

After a treatment of OA should I be able to last out until a Thymol treatment when the suppers come off or whould it be common to need a sugar dust in between?

 

[grizzly]

Here are my results

- pre Oxalic treatment ave <1 day
- 24 hrs after OA - ~ 200
- 48 hrs after OA ~ 50
-96 hrs after OA <10

Hi Jimbo
Did you treat with Apiguard a couple of months back ?

 

[ian]

HI

With the majority of hives they will not be treated again until the Autumn after a Winter Oxalic.

No harm in some IPM methods through the season though.

Spliting hives making nuc's/increase and the like is also a good form of Varroa control


Regards Ian

 

[BKF Admin]

Thanks for the advice Ian.

 

[jimbeekeeper]

Hi Jimbo
Did you treat with Apiguard a couple of months back ?

No I treated with Bayvarol, but see my post http://www.beekeepingforum.co.uk/showthread.php?t=387

for a possible explanation.

But other people have told me that mite drop is low? When you consider that from when I last treated there will have been 6 or 7 mite expansions. Others have had drops of 600+ over a week, therefore mine is less than that.

So varroa has had 8 or 9 weeks to increase numbers. This is about 6 varroa lifecycles and they can double their numbers each lifecycle. So a total drop of 100 doesn't sound too bad. But if it's 100 day after day that would be a worry.

Also as per Ians post above, I have done IPM through out the season, and all of my hives are the result of AS.

jim

 

[jimbeekeeper]

According to Martin (1998), one can estimate the total mite population by multiplying the daily drop by 250-500 when the colony is broodless, or by 20-40 when brood is present. Other authors come up with a spectrum of different conversion factors. Luckily, you don?t really need to know the total mite population?you only need to know if the natural daily drop indicates that the mites are at a ?tolerable? level on their growth curve. Note that stickyboard readings can be wildly inaccurate at the beginning or ending of broodrearing, as mites ?transition? from the adult bees to brood, or vice versa. Stickies are the best sampling method during normal broodrearing periods while brood is emerging.

Ref http://www.scientificbeekeeping.com//index.php?option=com_content&task=view&id=58

Therefore in my pre oxalic state of less than one mite per day (probably less ) taking the worst count of x 500 = 500 mites in the hive.

 

[grizzly]

Its life Jim but not as we know it.

No need to explain anything, i was just curious, Admin very kindly helped me tother day, and i have yet to check the drop on my largest hive.

Just noting what sort of drop people are getting after OA and after treating in Autumn as well.

 

[jimbeekeeper]

I know I have done everything for my hives, so regardless of the mite count (although I am still intrested what others report) I do not fall in the any of the following groups!

Three strategies that always fail when battling varroa are:

1. Denial??I haven?t seen any mites, so my mite levels must be low.?

2. Wishful thinking??I haven?t seen very many mites, so I'm hoping and praying that my bees will be OK.?

3. Blind faith??I used the latest snake oil mite cure, and it?s gotta work!?