Conditions for OA treatment

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Hi all

Just getting ready to try my first attempt at OA sublimation, and just had a quick thought about the best conditions to do it in. I know ideally it'll be cold to encourage clustering, but is it alright to do it whilst it's raining (which seems to be pretty much every time I'm at home) or do I need to wait for a clear period before carrying it out?

Thanks
 
Clustering? Does it matter?

Raining? Is it raining under and/or inside the hive?

Answering those question will allow you to anwer your own thread.
 
Clustering? Does it matter?

Raining? Is it raining under and/or inside the hive?

Answering those question will allow you to anwer your own thread.

I'd read that doing it when cold meant fewer bees outside the hive and more tightly clustered so the oxalic acid would coat more of them.

I'd have thought that if it's raining then the bees are more likely to be at home, but if treating them causes them to come spilling out then maybe doing it in the rain wouldn't be such a great idea. Hence asking....
 
more tightly clustered

Really? Loosely clustered might be better, perhaps?


causes them to come spilling out

Not really thinking here. Never heard of an entrance block? The clue is in the description!
 
Good question I thought. I only use trickling for oxalic as it seems a lot safer, and a reasonably tight cluster works well. The bees are also less likely to fly up when it is cool.

For sublimation you might have a dramatic effect on exposure rates if the cluster is loose and the bees very active. I'd have thought it was safer (for them) to do it when the bees are quiet.

If the forum's Doc Martin is feeling particularly grumpy he really should just not post until he is feeling more charitable.
 
I normally trickle OA between Xmas and new year. I prefer a dryish, still, cold day, but very much end up taking what weather I get given.

Under those conditions have never had any bees try to escape!
 
more tightly clustered

Really? Loosely clustered might be better, perhaps?


causes them to come spilling out

Not really thinking here. Never heard of an entrance block? The clue is in the description!

I'd have thought loosely clustered as well, however I'm not an expert on the permeability of bee clusters or the ability of sublimated OA to penetrate them.

Well as I'm doing OA sublimation I'd be blocking the entrance...but at some point I'll be unblocking it and at that point I imagine the bees might want to get out.
 
I'd read that doing it when cold meant fewer bees outside the hive and more tightly clustered so the oxalic acid would coat more of them.

Yes that all sounds fine, put the floor slides in, and try and do the treatment when the bees are not tightly clustered, more effective.
 
I'd read that doing it when cold meant fewer bees outside the hive and more tightly clustered so the oxalic acid would coat more of them.QUOTE]

As Rab says it doesn't matter what the state of the cluster is - sublimation dusts the cluster and it gets transmitted to others as they intermingle to take their turn for warmth or feed. What concerns me a bit is that it is normally best left until after Xmas (the mention of trickling is irrelevant in the context of this thread anyway) around new year. I always dump a half kilo of fondant (Apifonda, Ambrosia or bakers fondant whichever) on top of the frames to keep them going until spring, whether or not they need it as I don't think it worth checking. The beauty of sublimation is that one does not have to open the hive - trickling can't be done without opening up - and sublimation is now proven to be more effective too. It is essential however to seal the whole box up when virtually all the bees are at home so that none of them can escape being dusted. VERY important. I sublimate from below the mesh floor on a steel sheet that slides in the varroa tray slot with a wedge of foam to seal the air gap at the back and with front entrance block closed too. This avoids frying any of the bees when shoving the gadget through the front entrance beneath the cluster. Depends on the type of sublimation tool of course.
 
Well, there is rain and there is rain.... Surely depends on common sense? No sensible person goes out in an absolute downpour if unnecessary. Light rain is not a problem, providing the temperature is not close to zero.

Come on, common sense has to prevail at some point! Why open the entrance before the bees have quietened down? All very simple, when one actually thinks aboutfit and plans the job properly.

Don't you think the air temperature in the hive might rise a few degrees with a sublimator dishing out oxalic at around 160 degrees Celsius? I do. That might encourage quite a bit of activity, even if only at the periphery of the 'cluster'.

And yes, people responding about trickling on a sublimation thread is fairly inappropriate and meaningless.

Little things like whether the sublimator is actually inside the hive or below the OMF might make small differences to the operation. Perhaps just more thinking than a 'quick thought' might be advisable, particularly as we do not all think at the same rate.
 
As Rab says it doesn't matter what the state of the cluster is - sublimation dusts the cluster and it gets transmitted to others as they intermingle to take their turn for warmth or feed. What concerns me a bit is that it is normally best left until after Xmas (the mention of trickling is irrelevant in the context of this thread anyway) around new year. I always dump a half kilo of fondant (Apifonda, Ambrosia or bakers fondant whichever) on top of the frames to keep them going until spring, whether or not they need it as I don't think it worth checking. The beauty of sublimation is that one does not have to open the hive - trickling can't be done without opening up - and sublimation is now proven to be more effective too. It is essential however to seal the whole box up when virtually all the bees are at home so that none of them can escape being dusted. VERY important. I sublimate from below the mesh floor on a steel sheet that slides in the varroa tray slot with a wedge of foam to seal the air gap at the back and with front entrance block closed too. This avoids frying any of the bees when shoving the gadget through the front entrance beneath the cluster. Depends on the type of sublimation tool of course.

Is the point of waiting until after Xmas not waiting for a broodless period if you're only carrying out a single application?

I've been building something similar as I've got poly hives. Sheet that slides in the varroa tray slot, box built on the underside of it to house the varrox, with foam at the ends to make a seal. Seal the hive entrance and away it goes.
 
Temperatures of 5c or above are more effective, when the bees are not tightly clustered, 8 or 9 degrees works fine, just do the treatment in late afternoon when most bees have finished flying for the day, can be used with good effect if needed during spring/summer as well, for swarms/packages, artificial swarms, when the temperatures may be in the high teens or low twenties, no need to leave blocked in for fifteen minutes, five minutes after sublimation is fine.

Rain is okay, means most of the bees will be home, those big fishing/golf umbrellas are good to spike into the ground next to a hive while treating.

I always dump a half kilo of fondant (Apifonda, Ambrosia or bakers fondant whichever) on top of the frames to keep them going until spring, whether or not they need it as I don't think it worth checking. The beauty of sublimation is that one does not have to open the hive - trickling can't be done without opening up

So in your hives any benefit/advantage there may be of not opening them up in mid winter to treat is lost, as you open all of them anyway, yes.
 
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What's all this talk of 'spilling out' ? What you'll notice is that what follows OA sublimation is a serious case of 'no reaction whatsoever'. It's quite uncanny to witness this the first time you use sublimation. You'll probably be checking the pan to make sure that something has actually happened - I know I did. :)

My preference is to wait until there's a warmish 'flying day' during December, and then dose them in the early evening - my thinking being that they are probably only loosely clustered and will be stirring the stuff about more thoroughly - but I certainly wouldn't claim this to be essential, far from it - the important bit is just to get the stuff into the hive - the bees will look after the rest.

LJ
 
Thanks all for those very helpful replies. Might have to try to schedule the treatment for when I'm on paternity leave so I'll be around in the late afternoon! I knew there was a reason I was taking it :)
 
On an associated point I recently saw this technique demonstrated. The chap was lugging around a car battery to as power, which seemed a little over kill to me for half a dozen hives.

What, more portable, power supplies do people use here?
 
A car battery is very portable considering where some of my apiaries are located and even more so when I think of the location of colonies I have treated for other folk.....

Once my Land Rover is on the road it'll do as a portable power source for the bulk of my apiaries. That and long leads as per Hivemaker.
 
the important bit is just to get the stuff into the hive - the bees will look after the rest.

LJ

Is there a good piece to read somewhere about how the OA is ditributed after sublimation? It would really help this question to understand the dynamics. Is it passed by grooming, by further evaporation, by friction, by tansfer from hive surfaces etc etc.
 

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