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OAV with supers on

Posted: June 14th, 2017, 9:57 pm
by BDT123
So I know the 'rule', no treatments with honey supers on.
If a vapour barrier was installed prior to OAV, between brood chambers and honey supers, would that suffice for prevention of 'contamination' of honey with Oxalic acid? OA is normally found in honey but would the 'background level' be raised to unacceptable levels using a technique like this? I don't anticipate having to do this, mite levels are acceptable now, but if treatment became priority, what then?
Would removing the honey supers for a few days be a better option? Would like to hear other's thoughts.
Not dealing with a hundred hives, just a few.
Best to all,
Brian

Re: OAV with supers on

Posted: June 14th, 2017, 9:59 pm
by BDT123
I should have added, there is an upper entrance on all my hives, currently providing access to the honey supers directly.
Brian

Re: OAV with supers on

Posted: July 14th, 2017, 10:28 pm
by BDT123
So, no reply to this query, so is that assent or dissent? Why no response? No knowledge or no interest?
No matter, I have decided to wait until after harvest to do any treatments with OAV. I would still like some knowledgeable replies, however.
At least, let's have some discussion.
Best regards,
Brian

Re: OAV with supers on

Posted: July 16th, 2017, 6:28 am
by BadBeeKeeper
Since I lack specific education/knowledge/experience with that aspect of OAV, I would follow the 'official' guidance and remove the supers.

I have studied the methodology and results enough to know that I have little interest in using it because my current method (FA) provides the results I want without having to adhere to a rigorous application schedule of multiple treatments over time.

Re: OAV with supers on

Posted: July 16th, 2017, 1:18 pm
by Countryboy
So, no reply to this query, so is that assent or dissent? Why no response? No knowledge or no interest?
I have no experience using oxalic acid, not do I have any plans of using it anytime soon.
At least, let's have some discussion.
I also didn't say anything because I considered what you were proposing to be nonsense or a fool's game. If you have a nectar flow, the last thing you want to do is to put some kind of barrier between the brood boxes and supers, or remove the supers and deny the bees access to a place to store nectar.
So I know the 'rule', no treatments with honey supers on.
What about GRAS? (Generally Recognized As Safe) Does this 'rule' still apply to GRAS treatments?

Re: OAV with supers on

Posted: July 16th, 2017, 10:02 pm
by BDT123
We still have a good honey flow so I'm going to wait till end of July and after honey harvest.
Mite drops on the boards are still very acceptable, 2 hives still showing no natural drops.
The foragers seem to use the top entrance above the honey supers so I figured the separation wouldn't stall honey storage too much. Last inspection and hefting partial or mostly full supers has dissuaded me from trying to install a barrier. Not worth the work and aggravation, never mind the robbing possibilities.
So yes, CB, it was 'nonsense and a fools game'! But at least I figured that out before trying it!
Thanks for the replies CB and BBK!
Best regards,
Brian

Re: OAV with supers on

Posted: July 18th, 2017, 10:12 am
by cgybees
The initial scientific research into OAV indicated that the amount that passed into even uncapped honey was negligible, and well within acceptability for natural variation. Nevertheless, food guidelines have chosen on the side of caution in Canada and the US, and said, don't treat with OAV with supers on.

So Oxalic Acid, when heated, sublimates into a vapor directly from a solid, and then condenses from an organic vapour into crystals. To prevent it from coming into contact with your honey, your either need the supers off, or you need to block them with something air-tight. Personally, I'd say it's a great use for all those election signs - just slip one in there, treat, slide it out, move on.

With a standard vaporizer, you're talking 2 minutes heat time, 2 minutes cooldown time, 5 minutes with the hive blocked. You can overlap this and bring it down to 5 minutes a hive with a single vaporizer, you can run more than one, or for those who are talking large numbers of hives, the entry level units for ones that heat and force-air the vapor into the hive (reducing this time to 20 seconds a hive) have dropped from $3k down to $650 or so from Beemaid.

OAV, as an organic vapor, will lead to no resistant mite strains, and is 98% effective. The one and only 'gotcha' is thaty you should treat when you've got a high count, and absolutely before winter bees emerge - mite-ridden winter bees lead to weak colonies and much higher overwinter losses. So because you're dealing with something that doesn't pass into capped cells, you probably have to do 3 treatments, one week apart. You could do it when they're broodless, but that's really only good for a spring treatment. At 5 minutes a hive and 10 cents a treatment... It's worth it.

Re: OAV with supers on

Posted: July 18th, 2017, 10:39 pm
by BDT123
CGY - I am totally in tune with using OAV. My original post was about whether it was feasible to use OAV with a barrier between supers and brood boxes.
The reality has turned out to bee that it is impractical in the extremus to do so.
On one hive I have 4 medium supers in various states of honey 'completion'. About 25 kg per super, so moving 4 supers is not a simple exercise. And to do this every 4 days, not 7, is just too onerous a task to even contemplate.
Honey will be harvested, then treatments will begin.
Your treatment intervals are too far apart, if you are trying to catch a full brood cycle and phoretic mites between brood cappings. I go with 4 days.
My natural mite drop is really low, hopefully due to Spring treatments, so I have no sense of urgency to treat immediately.
Flow is still awesome up here.
Best regards,
Brian