OAV questions

[Psparr]

If they make it all the way to the tray. Good chance they will catch another bee on the way down.
Powdered sugar isn't healthy for bees.

[iddee]

You are correct, paus, EXCEPT, if the sugar removes 50 bees per day and the hive raises 75, what good does it do? Sugar helps, but is very inefficient.

[Acebird]

Just call me still mixed up.  The powered sugar makes the mites fall off. In a screen bottom board or in an oil pan as I use aren't the mites dead. Isn't the sugar a source of nutrition for the bees?

They will die if they fall into oil and they will die some time after they fall on a dry tray or bottom board because they can't get back on a bee.  Ants and other critters will clean them up if you don't.  Some ants can cause problems in a hive so the powdered sugar could be a bad thing.

[sc-bee]

Scientific Beekeeping:
Powdered Sugar Dusting

The practice of routinely dumping powdered sugar into beehives has become the rallying call of the Varroa impaired. Coat your bees with powdered sugar and Madam Mite will lose her grip and fall to her demise through the open screened bottom board, or so the theory goes.

In actual practice dusting with powdered sugar does only one thing. It removes somewhere between thirty and forty percent of the Phoretic mites from their temporary adult bee hosts. That?s it! During the active brood rearing months, approximately sixty percent of a colony?s mite load is in the capped brood, dusting has absolutely no affect on this segment of the population. The Phoretic mites that are removed through the dusting process are replaced as the colony?s mature brood emerges, hence the need to dust on a regular basis. It?s a vicious cycle, with literally no end in sight! A 2009 study out of Florida found that dusting colonies with 250 ml (1 cup) of powdered sugar at two-week intervals, over the course of ten months ?did not significantly reduce the total number of mites per colony, the number of mites per adult bee, or the number of mites per capped brood cell.? Furthermore, even though the test colonies were dusted throughout the relatively broodless winter period, there were still no ?significant differences in mite populations between dusted and undusted colonies.? In addition, the study appears to confirm earlier work by others ?that at lower mite densities, the reproductive rate of Varroa increases. Therefore, the mite may be able to compensate for population loss due to dusting by increasing its reproductive rate.?2

Powdered sugar dusting is at best a labor intensive short-term means of Varroa control. I refer to the dusting procedure as the here and now, or pay as you go method. Its only long-term benefit is a false sense of security, which will be replaced by disaster once you stop dusting. Like its predecessor, the screened bottom board, this method of controlling Varroa is an idea whose time has passed. Serious beekeepers need to advance their agenda and strive for realistic longterm solutions to the Varroa dilemma.

[sc-bee]

Bee Informed page:
Always be sure to monitor your bees for varroa mites so that you know the mite load before you prophylactically treat your colonies. If you treat with the same synthetic chemical at each treatment, this continual exposure may cause the mites to develop resistance to that specific varroacide.

Additionally, treatments can negatively impact honey bee larval development and adult life span and should be applied only after the mite levels have crossed the threshold for treatment. That threshold is different for different operations.  It is not likely that mites will develop resistance to a naturally occurring compound such as formic or oxalic acid as these acids desiccate mites and it is difficult to see a resistance developed to this mode of action.

[sc-bee]

Does any identity have any documentation on what a healthy mite looks like compared to those killed by OAV?

Here are the pics: I imagine a lot of the damage issue has to do with a bee having an exoskeleton and a mite being soft tissue...



Underside of varroa mite (one leg is missing) taken using a scanning electronic microscope Photo credit: Bee Informed Partnership

[GSF]

That bottom picture looks like what acid would do to skin.

[Dallasbeek]

If they make it all the way to the tray. Good chance they will catch another bee on the way down.
Powdered sugar isn't healthy for bees.

Store-bought may not be healthy for bees, but if you run granulated sugar through a blender to make it super-fine, it doesn't have the corn starch that the store stuff has, so it's just sugar.  Is sugar not healthy for bees?

[Jim134]

If they make it all the way to the tray. Good chance they will catch another bee on the way down.
Powdered sugar isn't healthy for bees.

Store-bought may not be healthy for bees, but if you run granulated sugar through a blender to make it super-fine, it doesn't have the corn starch that the store stuff has, so it's just sugar.  Is sugar not healthy for bees?

   From what I understand powdered sugar whether it has corn starch in it or not. If it gets on the lava it will dry it out.

     BEE HAPPY Jim 134 :)

[Michael Bush]

Here's why no treatments work very well:
http://www.bushfarms.com/beesvarroatreatments.htm

Any treatment that is only marginally effective works even worse.

[sc-bee]

Here's why no treatments work very well:
http://www.bushfarms.com/beesvarroatreatments.htm

Any treatment that is only marginally effective works even worse.

And this makes no treatment good why? Maybe it is just my night shift brain fog or my ignorance... but I will admit... I don't get it  Maybe I can read it when I am awake and understand....

[little john]

With the varroa mite, there are basically 3 approaches to the problem:

The first is that being peddled by supporters of 'The Establishment' - that is, that only patented (and therefore expensive) products should be used, regardless of their efficiency, toxicity and so on.

The second is the opposite of this - that Vapourised Oxalic Acid (which, incidently, enters the hive as a fine crystalline powder produced by the action of vapourisation, and is NOT a vapour or gas as many believe), which - although the initial cost of the equipment is high - then costs mere pennies per treatment, safe (for the bees), non accumulative and thus non-toxic.  But again - 'The Establishment' have decreed that in your country only Oxalic Acid Dihydrate with the right label (creating yet another monopoly) can be used - but not the regular, 'off the shelf' stuff which is exactly the same - and far cheaper.

The third approach is not to treat, and either a) select out hygenic queens and sell them at a good price (even though the hygenic characteristics are not guaranteed to persist, so it may be an expensive and temporary 'Band Aid' solution. Or, b) adopt a Typhoid Mary, 'I'm Alright Jack' approach, in which an apiary develops a working tolerance to Varroa, whilst continuing to harbour viable numbers of the mite, which then go on to spread Varroa infestation to neighbouring apiaries.

I don't have a mite problem - never have - but then I use VOA.  I'm fairly sure that many of my colonies have developed hygenic behaviour, but I continue to use VOA on all colonies nevertheless, in order not to infect colonies outside of my own apiary.
LJ

[Acebird]

non accumulative and thus non-toxic.

I am not convinced of either.  The acid has to go somewhere and seeing as it is readily dissolved in water I think a lot stays in the hive and a whole lot is accumulating outside the hive.

b) adopt a Typhoid Mary, 'I'm Alright Jack' approach, in which an apiary develops a working tolerance to Varroa, whilst continuing to harbour viable numbers of the mite, which then go on to spread Varroa infestation to neighbouring apiaries.

I believe the opposite happens.  If you cannot kill all the mites, and you cannot, then the stronger ones are left to go infest your neighbors hives.  The "I'm Alright Jack" approach allows the weaker bees to die and doesn't build a stronger mite.  LJ why are some "I'm Alright Jack" approach beekeepers succeeding?  Why hasn't Europe been free of mites if OA really works?  If OA did work it would not just be legal we would be forced to use it on every hive to exterminate the mite.  But 30 or so years has proved that it is just another band aid that builds dependency AND is dangerous to the user which in many cases is unqualified to preform the task.

[KeyLargoBees]

I run screened bottoms but leave my inserts in for a week after a treatment...i see fine crystals on the board that have fallen through the screens....so for me Ace the VOA drops down to the insert/ground and is blown or washed away....in a hive with a solid bottom i am not sure what would happen to it but I bet the bottom board will be squeaky clean with no stains on it :-)

[Acebird]

According to some posts that I have read the bees carry out the crystals and dump them outside the hive, how far I don't know.
What I surmise is that the acid will not stay in the crystallized mode if it is in the presence of water.  We know up here that condensation is quite prevalent in the spring and fall when this method of killing mites is mostly used.  That suggests that some OA does not get carried out of the hive and then the question is well where does it go or get consumed?

[Jim134]

What the brainiacs tell me. Some of the OAV reconstitute to formic acid. Who knows this is true or not.

             BEE HAPPY Jim 134   

[sc-bee]

The second is the opposite of this - that Vapourised Oxalic Acid (which, incidently, enters the hive as a fine crystalline powder produced by the action of vapourisation, and is NOT a vapour or gas as many believe),

Agreed, which cause the respirator confusion if you use one. The OA  goes through sublimation for a very short time and then quickly cools and becomes a particlate (so I  have read) . The white cloud you see is indeed a particulate so a P95 cartridge should be good. But why not take the conservative approach if you are going to VAO and get a OV/P95/AG combination. Then there is no doubt. IMHO

[Yukon Bees]

Just completed my 1st OAV treatment on my 3 hives. Very happy with the results.

Uphere in the Yukon the queens have pretty much stopped laying so my hives were mostly broodless (less than 1/4 of one side of one frame). I had one infested hive (pre-treat mite drops of anywhere from 10-50 mites per 24h, the other two hives (1st years) had 0-5 mites per 24h)
Results: (the boards were cleaned after every check)
Hive 1 24h (500-700 dead mites after treat); 48h (+500 mites); 72h (300-400 mites); 96h (200-300 mites); 120h (30 mites)
Hive 2 24h (100 mites); 48h (140 mites); 72h (35 mites); 96h (25 mites); 120h (1 mite)
Hive 3 24h (17 mites); 48h (80 mites); 72h (20 mites); 96h (20 mites); 120h (2 mites)

I will be conducting a second treatment tomorrow to see how effective the treatment has been and too make sure most mites are dead. We've had frost every morning for the past 2 weeks with morning lows of -5C and daily highs of 12-16C. The hives are pretty much ready for winter with ~100lbs of honey and they will have a medium of with 1.5" of fondant as security. I use poly hives and I will put on an extra bubble foil wrap this year....I have a feel that it will be a cold one this winter.

[Yukon Bees]

Photo for day 5 and the setup. I use poly hive so I did the treatment through the screened bottom board. I will use slightly more OA as recommended as some of OAV crystallizes on the metal mesh of the screen board. I also run it for 3 mins instead of 2.5 mins as recommended.

[Dallasbeek]

Yukon said

"Photo for day 5 and the setup. I use poly hive so I did the treatment through the screened bottom board. I will use slightly more OA as recommended as some of OAV crystallizes on the metal mesh of the screen board. I also run it for 3 mins instead of 2.5 mins as recommended."


Please explain how you vaporize "through the screened bottom board".  Do you have it sealed under the SBB or is it open?