[knengli]

Everything I’ve read says that I should not OA My girls when I have a honey super on the hive. Is it permissible to remove the honey super, oa vaporize the hive and then replace the honey super at a later date.? If so, how long should I leave the honey super off the hive?

 

[JTGaraas]

The vaporized oxalic acid will permeate the brood boxes and make the crystals within minutes, if not seconds. I replace the supers after all the hives in the apiary have been treated sequentially (about 20-25 minutes after that specific hive’s treatment). I believe it could be done as soon as you do not observe the gaseous vapor, as crystallization has already occurred. I vaporize from the top using an acrylic topped box so I can watch.

 

[bushpilot]

The vaporized oxalic acid will permeate the brood boxes and make the crystals within minutes, if not seconds. I replace the supers after all the hives in the apiary have been treated sequentially (about 20-25 minutes after that specific hive’s treatment). I believe it could be done as soon as you do not observe the gaseous vapor, as crystallization has already occurred. I vaporize from the top using an acrylic topped box so I can watch.

Does the vapor fall into the hive? i visualize that the hot vapors would rise, therefore the traditional way of going from the bottom. But that is just me thinking, curious to know.

 

[JTGaraas]

The grey vapors rise toward the acrylic top and immediately flow back into the frames; there will be vapors coming out of the bottom entry if you do not cover. Always wear a respirator.

 

[knengli]

The vaporized oxalic acid will permeate the brood boxes and make the crystals within minutes, if not seconds. I replace the supers after all the hives in the apiary have been treated sequentially (about 20-25 minutes after that specific hive’s treatment). I believe it could be done as soon as you do not observe the gaseous vapor, as crystallization has already occurred. I vaporize from the top using an acrylic topped box so I can watch.

If that be the case, any crystallized acid on forgers may make its way back into the replaced honey super. But, Alternatively, the quantity Of acid That would get into the honey may be insignificant.

 

[John Davis]

What you see as grey "vapors" is the cloud of recrystalized OA.
It sublimates, going directly from a solid to a vapor (like dry ice)
As soon as it's temp falls below the vaporization point it recrystalizes.
That is very close to the wand.

 

[Alex Madsen]

I put newspaper (amazon shipping paper) in between the supper and brood box before OAV. The bees remove it in a few days. That way I only have to go into the hive once. I make a few small cuts in the paper to speed up the process. I do this when I have a mite emergency and am out of MAQS or if it is a new queen.

 

[JimD]

I think using some of these left over political plastic cardboard singns are their best use. Just slide one between the supers and the deeps and remove a little later.

I also use them for hive stand platforms as it seems not as many insects will climb up and over as the hive bottom just sitting on a brick or such.

Also use them on top of the hive cover with a brick on top to add shade to the front of the hive and to help protect from heavy thunderstorms we have around Houston.

 

[davemal]

I did some experiments earlier this year regarding OAV. I think you might find these interesting.

https://www.youtube.com/watch?v=K5dk52VMUB8
https://www.youtube.com/watch?v=qpTjPWW9Pe8

 

[JTGaraas]

davemal - your experiments appear to have validated the effectiveness of “top vaporization”. I have found it to be a simple process, and I do not have to mess with my mouseguards (which are used year-round).

 

[johno]

Some nice videos Davemal, You have confirmed what I have been advising beekeepers for the past 2 years.

 

[crofter]

Well done davemal;

That puts to rest quite a few misconceptions; certainly would be a lot easier and apparently more effective when treating a winterized hive. No humping over to reach a bottom injection hole!

thanks,

 

[snl]

Excellent videos with good descriptions. Either top or bottom vaporizations work well on 2 box brood chambers (very few have 3 brood boxes). Bottom vaporizations may be easier because there is no need for a shim/rim on a top. Just drill a hole.
To each beekeeper their own method.
The key is just to treat.

 

[JimD]

Looks good but I have the old econo model that works well but still needs to be shoved in the bottom.

Another thing not discussed is are the supers with honey capped or not? If you are cutting the caps and not scratching them how much exposure is there to OA for personal use.