[cristianNiculae]

Hi,

I've done my first jar sugar roll this Spring and found 0 infestation. Most of the mites are now under cappings.
I decided not to treat at the moment and will do another test in a month. It's my first Spring with bees.
The hive that I tested has 8 deep frames of brood and started working the second brood box.


Is this a good decision?

 

[Oldtimer]

This depend on what is normal in your area Cristian. What do other successful beekeepers near you do and what kind of treatment are you thinking to use?

Sometimes sugar roll do not find all the mites so also look carefully for any unhealthy bees or dead brood and perforated brood cappings.

 

[cristianNiculae]

No "successful" beekepers around, in fact they just treat, no matter what, using amitraz all the time (they have no concern regarding contamination of comb/honey, developing amitraz resitant mites). They don't test for mites - nothing to learn from them regarding tratments.

The bees look healthy to me: no DWV(except for one drone I've seen yesterday), no perforated cappings. The mite levels were low in Autumn also - bellow 2% - when I treated several times with OAV and had a few hundred mites dead.

I know it's said about formic acid killing mites under cappings but I would only go for a flash treatment because I don't want to risk my only breeder hive from wich I want to graft when the time comes.

Unfortunatelly Apinovar haven't done studies regarding flash application during Spring.

http://apinovar.com/articles/flash.en.html

Flash should also be experimented during Spring. We found that small or medium size colonies are affected in their development when they are continuously exposed to formic vapours for a long period. We suspect this side effect could probably be avoided with flash.

Does anyone know about the existance of such study?

I will probably use the drone comb removal method until late Summer and only if counts exceed 2% treat. Do you think that's OK?

 

[Oldtimer]

Here's some info about formic flash treatment, it's also what I do for a fall (autumn) treatment. Depending on local climate it could be unreliable for a spring treatment.

http://www.wvu.edu/~agexten/varroa/VarroaMitesppt.pdf

 

[cristianNiculae]

Thanks.

What are the factors that makes it unreliable for a spring treatment? Temperatures?
Do you think it can work without HBH using only 43% FA concentration?(no such thing in my country)

So it really kills mites under capped cells. Great!

 

[Oldtimer]

Yes the temperatures have to be right, if not it is unreliable.

Yes I use it without HBH although I do lose a few queens, maybe 5%. Doesn't matter to me cos I just break those hives down for nucs as I'm making nucs to sell all the time. But it would matter if somebody did not want to lose queens. I experimented with lemongrass oil & found when I used a drop of that in each fume board no queens were lost although didn't do it on enough hives to be certain of true results.

It does kill mites in brood cells but the success of this varies with temperature and humidity. It has taken me several years to really find out how to get good results with formic flash treatment, it is not always quite as good as the article makes out but now I get good results cos I've learned how to adapt it with different weather conditions.

 

[Oldtimer]

Oh should have said, about the 43% acid concentration yes that is fine just increase the amount by 20 to 25 percent so the right amount of acid still goes in the hive.

 

[cristianNiculae]

That's valuable info to add to my personal bee files. Thanks.

5% is really acceptable loss and if you have spare queens, wich I plan to, then you're fine.

I will try it on the other hive this spring to see how it goes and then on the breeder hive when it's job will be finished.

 

[cristianNiculae]

Oh should have said, about the 43% acid concentration yes that is fine just increase the amount by 20 to 25 percent so the right amount of acid still goes in the hive.

That means if I have 60% AF:

(90+15) × 60 ÷ 43 = ~146 ml/double
Corect?

Can I use the pads on frames with that freezer paper above it instead of the aluminium stuff?

Do you take the power of the colony into consideration? If I have a hive in a single should I use half the amount?

The amounts/concentration are almost doubled in this study comparing with the apinovar study.

 

[Oldtimer]

Pads on frames are not as good, the fume boards have an air space celled a mixing chamber, which the designers belief very important.

yes the power of the colony is the other factor, if the hive is full of bees the acid does the best job. Weak hives I don't use this method.

For single brood 85 mls at 50%, double brood 100 mls at 50%. Last round I put 120 mls in the doubles and have got very good results.

 

[winevines]

See http://scientificbeekeeping.com/miticides-2011/
It is an extensive discussion of dealing with varroa.

 

[cristianNiculae]

This looks promising.

Regarding the materials used: it's hard to find aluminium plates and I'm thinking on using aluminium kitchen stuff. I guess it's fine except that it needs ocasionally replaced.
The wire mesh bellow the pad: does it really need to be aluminium? cause I have no ideea where to find this stuff.

I guess you use Al because of the acid corosity. How about galvanized zinc plate and some other anticorosive mesh?

 

[crofter]

I have used plasticized fiberglass window screen around formic acid. You could probably use 8 mil polyethylene film over thin plywood to make the top of the shelf to test the procedure. Not as neat as aluminum but would be functional and cheap. Adult diapers makes good dispersal material to go on top of screen.