Varrox under OMF Floor ? dose 1.0g or 1.5g ?

[Nige.Coll]

Isn't the hive more likely to be clustered during a broodless period?

yes it is
I've not seen or heard of any ill effects on brood when using vapourised OA.

As soon as anyone mentions OA everyone thinks about the drizzle method used in winter when there is no brood. That method has to be done when broodless because it harms them.

Vapourising is completely different.
It says in bold type on the instructions that it must be done when temp is above 4 c.
It also says that treatment may trigger a cleansing flight.

The method i use is slightly different from the instructions as it says remove the varrox after 2 mins of cooling and re seal the hive. I don't do this as when I did I was exposed to the OA fumes and didn't like it, so i wait for the full 10 mins before removing.

 

[Haywards]

This is my first bee winter and I plan to vaporise with Varrox. However, since Christmas the temp has never been above 4 c here in hilly Derbyshire and the forecast for the coming week is snow and cold. I'm starting to get concerned that by the time it warms up there will be brood and this might be damaged. Should I just get in and do it? What will the consequences be if I wait for the temp to rise?

 

[einsteinagogo]

This is my first bee winter and I plan to vaporise with Varrox. However, since Christmas the temp has never been above 4 c here in hilly Derbyshire and the forecast for the coming week is snow and cold. I'm starting to get concerned that by the time it warms up there will be brood and this might be damaged. Should I just get in and do it? What will the consequences be if I wait for the temp to rise?

I was also waiting for a response to your post, abot the 4c and above, the reason why... went today and the apiary temp was -1c, so postponed, for a few hours.

Before posting this here, I've read on the these forums, to be effective, temps must be above 4c, and ideally 8-9/10 (I think that was Hivemaker's post!), due to bees clustering more tightly.

It's post#12 in this thread.
http://www.beekeepingforum.co.uk/showthread.php?t=32136&highlight=oxalic+hivemaker&page=2

Edit:- Added

5 day forecast gives, Friday 4c and Saturday 5c, so postponed until then!

 

[wessexmario]

WARNING !
DO NOT ADD SUGAR TO THE OA IF VAPORISING !!!

what would happen if you did?

would it just produce toffee?
of would there be a bigger chemical reaction?

 

[Helen]

Today, I vaporised my bees for the first time. I made a vaporiser from the 170C PTC Heater available off ebay. (Sorry, cant post link as forum wont allow me to) I made a small container on top, using a bit of 20mm copper pipe. The OA goes directly onto the heater, the copper pipe just holds it in place on the ali plate. Connected the whole thing to the end of a long BBQ rotisserie bar, which has a wooden handle at the end. I also connected a digital food probe to it, similar ones you can find for a few pounds in Amazon or ebay. A metal probe at the end of a long wire connects to heater, and a digital display shows temperature. So I could monitor the exact temperature of the heater whilst it was in the hive.

I have Dartingtons, so decided to wrap the whole hive in a large sheet of clear plastic. I put this under the feet, and pulled it up over the top, with a bit of string around the middle to hold it. A small hole in the side of the plastic allowed me to put the heater in directly under the cluster. The heater went below the mesh floor.

So, put OA onto heater, popped it into the plastic tent, connected it up and watched the temp gauge. Heated it up to 170C then disconnected and removed it. The container was empty, no OA left. I could hear the bees reacting ... a little buzzing and a few bees flying around under the hive. I could also hear them throwing bits of sugar down through the mesh floor. Maybe cleaning themselves due to the fumes? Is that normal?

After 10 minutes, I gently removed the plastic bag and on to the next hive.

I used 1g of OA this time. Next time, I may use a bit more.

With the plastic tent, there was no seepage or escape of fumes at all. Plastic bag itself was easy to put on, just raised each foot a few mm and slid it under. Surprisingly easy.

 

[Erichalfbee]

It seems you have a lot of dead space doing it this way. Did you close off the floor under the mesh?
Floor closed and sublimating under the OMF I would have used 3 maybe 3.5g (I used 3g on top of the OMF in my 14 x 12s with nadired shallow.
As for buzzing my bees gave me a definite roar!!!
Somebody with Dartingtons will be along soon. I'm sure pargyle has a long deep hive.

 

[jenkinsbrynmair]

what would happen if you did?

would it just produce toffee?
of would there be a bigger chemical reaction?

sugar, acid - reminds me of an explosives recipe we toyed with at the defence academy

 

[pargyle]

. a little buzzing and a few bees flying around under the hive. I could also hear them throwing bits of sugar down through the mesh floor. Maybe cleaning themselves due to the fumes? Is that normal?

.

??? Sugar ? Why ???

You might find that 1g of OA in a Dartington is less that you would need for an effective treatment. My LDH has 25 14 x 12 frames and I suspect your Dartingtons are going to be at least 18 frames if they are standard ones.

How many frames are in use ?

As EricA said - you might have rather a lot of space in your 'bag' doing it your way - you might consider making a shallow tray to fit under the mesh floor for when you want to do your OA - put your vapouriser in the drawer and tape round the gap between the drawer and the hive to seal it. The hive should really be fairly air tight above the floor except for the entrances which you can also seal with tape. I don't really see the need to bag up the whole hive ?

RAB is pretty expert with Dartingtons so if you ask him nicely he may well give you some better advice as my LDH is a bit different to a standard Dartington as I built it with a tray under the mesh floor so pretty easy for me.