# Oxalic acid vaporizer



## John Davis (Apr 29, 2014)

Pay a little more and get the varrox vaporizer. It will last a lifetime, connections are waterproof. Oxalic acid sublimates, goes directly from a solid to a gas, think like dry ice. 
What looks like liquid is the water that is bonded in the acid, it absorbs moisture from the air. 
With a pan type vaporizer the acid starts to re-condense back into tiny crystals pretty much as soon as the vapor leaves the pan. 
The white "smoke" is the cloud of tiny crystals that you want to coat the bees and hive surfaces. 
It won't get hot enough to break down the oxalic. 
The pan however will continue to heat if left connected to the battery after the acid is vaporized.


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## snl (Nov 20, 2009)

OA only decomposes to Formic and Co2 in the lab (both of which are colorless). If you’re seeing white crystals, that’d be OA. JD is also correct about the Varrox. It’s the only steel/stainless wand vaporizer on the market and is water dunkable to cool it down between vaporizations.


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## johno (Dec 4, 2011)

Dphilipm, do yourself a favor and read about the Band heater vaporizer in the equipment and hardware section of Beesource and if you cannot build one buy one as they are cheap and effective. You will find to control varoa requires many OA treatments and with this type of vaporizer the treatments can be made from behind the hive without having to remove the entrance reducer and upset your bees also possibly frying a few. With 10 hives you can get the job done in around 10 minutes so I would suggest that you do a little research.


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## enjambres (Jun 30, 2013)

When using a Varrox, "upsetting the bees .....and frying a few" is a rare occurrence if you use correct practice. My bees are unperturbed by the OA, and I bet I've only fried up a couple of dozen bees in all the years and more than a thousand cycles I've done.

Also keep in mind that you cannot use OA when you have honey supers on the hive (unlike formic acid) and also that OA is much less effective when there is brood because, unlike formic acid, it doesn't kill varroa protected with the pupae under the wax cappings. For these two reasons, many people use formic acid in the warm months. But, as you well know, formic has its own drawback in that it has hard temperature upper limits which are tough to work around in the summer, in the south.

OTOH, if you have a summer dearth when honey supers can be taken off, and perhaps a dearth-prompted slow down in brooding that would be a good time to run an OA series. You just have to look over your whole bee-year and find places where you can seize just the right conditions for OA, and then build your year-long mite suppression plans around those opportunities.

Ex: where I live in the north the natural early winter brood pause happens just before a long 2-4 month period when my bees don't fly much, and rarely leave my apiary. Treatment at just the right point around that time kills nearly all the mites and then the weather prevents re-infestation. If you think about your whole year, as well as the biology of the mite's reproductive cycle, you'll likely find some windows where it will work well.

I have had a Varrox for several years and done more than a thousand treatments with it, I can recommend it wholeheartedly as being a sturdy, reliable, easy to work, tool. I use a small lawn mower battery which will run 20 cycles on a charge. If you've got more hives than that in one yard, you ought to be thinking about a ProVap. But up to about 25 hives, a Varrox is all you need. I bought a cheaper vaporizer first, not an inexpensive one, just a somewhat less expensive one. It failed after a year or two. I'd have been a $100+ ahead if I had bought a Varrox the first time, since I'd have only had to buy it once.

Nancy


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## johno (Dec 4, 2011)

Now the pan type of vaporizer is a 20th century tool and has performed well in its time as there was not any alternative for sublimating OA, however we are now in the 21st century and it is time to move on to newer technology. I will treat my 20 odd home hives in about 20 minutes and I use a 100 ft extension cord and it is so easy on the bees that I rarely use a veil when treating and in the 2 plus years I have used this vaporizer in more than a thousand total treatments have not fried a single bee. In my out yards an inverter clipped to my trucks battery and a 50ft cord is all it takes to treat those hives in about 10 minutes, again no veil and no dead bees and as the Op is in Alabama, too much time spent all kitted up in the hot summer sun is not a plus.
Johno


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## Kamon A. Reynolds (Apr 15, 2012)

johno said:


> Now the pan type of vaporizer is a 20th century tool and has performed well in its time as there was not any alternative for sublimating OA, however we are now in the 21st century and it is time to move on to newer technology. I will treat my 20 odd home hives in about 20 minutes and I use a 100 ft extension cord and it is so easy on the bees that I rarely use a veil when treating and in the 2 plus years I have used this vaporizer in more than a thousand total treatments have not fried a single bee. In my out yards an inverter clipped to my trucks battery and a 50ft cord is all it takes to treat those hives in about 10 minutes, again no veil and no dead bees and as the Op is in Alabama, too much time spent all kitted up in the hot summer sun is not a plus.
> Johno


That is why pro vap is what we use! Fast and effective. A pan vaporizer stills works fine for a backyard beekeeper though.


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## msl (Sep 6, 2016)

> OA only decomposes to Formic and Co2 in the lab


That "fact" seems to get circulated a lot, but I haven't been able to find anything to back it 

The EMEA says that 54% makes it in to the hive, 1% turns in to FA the rest Co2/water 
https://www.ema.europa.eu/documents...ommittee-veterinary-medicinal-products_en.pdf
_

"This small electrical device can be inserted into the hive and allowsthe evaporation of oxalic acid in the closed hive55. During heating, approximately half ofthe oxalic acid disintegrates into harmless carbon dioxide, while the remainder forms anoxalic acid precipitate which settles on the bee,"_https://www.researchgate.net/publication/241209497_Parasites_of_the_Honeybee

and of course your repost of Dave W 


snl said:


> When heating, about half (46%) of OA decomposes into harmless carbon dioxide and water. Other half (54%) vaporizes and forms fine drops and dusts of OA that precipitates everywhere in hive. Because of this even distribution of fine particles, high and consistent efficacy against Varroa mites is possible [[/COLOR]http://www.mellifera.de/Engli2.pdf - Accessed 7/13/04].


that was with a panheater type device, I have often wondered if the bandheater ones have more breakdown... I know Randy O didn't see any diffrenace in mite killing between the 2 in his limited experiment. 
But locally I am hearing about guys with homemade band heater units doing 4 weekly winter brood less treatments do to a high mite drop on the 2nd and 3rd treatment. To me that's screaming there is something wrong with their set up.


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## johno (Dec 4, 2011)

Funny thing when my OA hits the bottom the temperature drops to around 320 F and only when most of the OA has sublimated does the temperature rise above 400F so I guess plenty of H2O and plenty of white fog which is known to be fine crystals of OA but not a sniff of FA. Now this whole thing about OA is when you get the Oa in contact with a mite or mites they die there is no argument aboutthat the trick is to get the mite in contact with the OA and the more treatments you do the more the equation will move in your favor. Now if it is a PITA to do these treatments you have a problem but if it is quick and easy there is a possibility of success. I dont care what EMEA says.
Johno


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## Eddie Honey (May 30, 2011)

My only drawback to oxalic is I have to shave my beard off because I wear a negative pressure respirator.


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## dudelt (Mar 18, 2013)

I started out with the inexpensive Varrocleaner from Oxavap.com. It worked like a charm for 2 years and then the number of hives increased and I got the Provap. I currently lend out the Varrocleaner to beeks in the area free of charge. I believe it heats up faster than the Varrox but it definitely is not built as well. If you want an inexpensive unit, I strongly recommend it. The first hive you save from mites will pay for the unit. Once you get more hives, you may want to upgrade but for a single hive or a few, it works great.


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## snl (Nov 20, 2009)

msl said:


> But locally I am hearing about guys with homemade band heater units doing 4 weekly winter brood less treatments do to a high mite drop on the 2nd and 3rd treatment. To me that's screaming there is something wrong with their set up.


If they're seeing crystals, it's OA. Now is there a good distribution within the hive? IDK. They would need to open the hive to see.


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## johno (Dec 4, 2011)

Some beat on OA claiming all sorts of reasons it does not work, yet give me one miticide that can kill 100% of your mites in a day? There are none even Formic acid does not kill them all, it can kill a lot plus a lot of bees and if the temperatures are not where you want them to be over a 7 day period mite kill can be mediocre or bee kill very high. So there are variables with every thing that you use. I try to go into winter with colonies no more than 3 mediums but have ended up with colonies so large that I could not get them smaller than 4 mediums so those probably do not get the same amount of vapor coverage then the ones that are 2 boxes high, yeah I know those hives should have been split, but I split so many as it is and I do not know what to do with all those bees. I am desperately trying to get down to 25 colonies from around 40. what this means is that all the different size of colonies would vary in the amount of any treatment they got. Enter OAV it is cheap it is easy to apply it has no ill effects on the colonies and has no residual effects so what is needed is a regimen of treatment that will prevent the mite population from getting out of hand and that is where we are at this moment, playing with all sorts of treatment timing to try and find the best result for the least input and we still have some unexplored avenues.


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## AHudd (Mar 5, 2015)

I like OAV.

No stringent temp. requirements.

No lengthy treatment times.

Can be repeated as needed.

No warnings about Queen or brood mortality.

Works well when brood is present with multiple treatments.

Works extremely well during brood-less periods.

Does not penetrate wax.

Inexpensive. After purchasing or building your device it gets really inexpensive.

Alex


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## SeaCucumber (Jun 5, 2014)

I would like to know a good treatment schedule. I would like to have TF (treatment free) bees next spring. Troy Hall said he has many years of success TF in New Hampshire with 50% loss/y. I plan to get his queens next spring and breed those.

My vaporizer is an immersion heater (<$10). I got 3 packages and did a small dose in late spring. Vaporizing took ~1 min each. All the queens failed, and I was swapping brood weekly. They made great queens. All 3 hives have lots of brood and food.

I need to do a serious treatment before and during winter. This should involve several treatments, and possibly splits or caging queens. What should the schedule be? My bees are probably Italian. Troy said his queens are carniolan/Russian. They are red/black. Once I get his queens, I'm going TF.


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## JWPalmer (May 1, 2017)

David, there is no defined treatment schedule per se. Most people agree that three or four treatments five to seven days apart will get the job done. Mites reinfest hives so you have to do follow up treatments throughout the fall. I do a single application and count dead mites. If there are less than 20 on all the hives, I won't do a second application. But if numbers are higher, they get it every couple of days until the drop numbers come down. I consider the apiary as a single unit so even if 1 out of 20+ is high, they all get treated. My supers came off two weeks ago and I am starting my first round of OAV this weekend.


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## Plannerwgp (May 18, 2019)

I am always interested in the discussions regarding Oxalic Acid treatment and wonder how individuals using this chemical protect themselves from the dangers associated with the use of it. I was about to purchase a vaporizer and then read the warning labels regarding OA and decided I would prefer to protect my health over that of the bees. I am currently looking for other treatments that may be less damaging to my health. The use of OA does require a respirator, protective clothing and gloves. That sort of tells you that you're dealing with a serious chemical that may damage your health if you don't properly protect yourself. I hope you all protect yourself, and read the labels before using.


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## JWPalmer (May 1, 2017)

It true that breathing OA crystals can cause respiratory distress, but that is why one must wear an approved respirator. As far as other concerns after reading the warning label, just for grins, read the warning labels on the products you use daily in your laundry room. Or the in the garage. Ever read the warning label on a can of spray paint? Yet we are familiar with these chemicals and use our own judgment as to the exposure risk we are willing to take. The risk of using OAV is minimal as long one exercises reasonable caution and wears the proper PPE.


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## crofter (May 5, 2011)

JWPalmer said:


> David, there is no defined treatment schedule per se. Most people agree that three or four treatments five to seven days apart will get the job done. Mites reinfest hives so you have to do follow up treatments throughout the fall. I do a single application and count dead mites. If there are less than 20 on all the hives, I won't do a second application. But if numbers are higher, they get it every couple of days until the drop numbers come down. I consider the apiary as a single unit so even if 1 out of 20+ is high, they all get treated. My supers came off two weeks ago and I am starting my first round of OAV this weekend.


There are some people who feel the seven day spacing between treatments was part and parcel of getting swift passage of approval. I think not many sideliners or commercial operators are spacing treatments more than 5 days apart. They seem to agree on the idea of repeating till the numbers come down, not for any prescribed number like 3, 4, 5, etc. If you are in an area with high surrounding bee numbers and are getting a lot of in drift of mite carrying visitors, keep a watch on resurgence and be prepared.


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## Live Oak (Oct 11, 2008)

snl said:


> OA only decomposes to Formic and Co2 in the lab (both of which are colorless). If you’re seeing white crystals, that’d be OA. JD is also correct about the Varrox. It’s the only steel/stainless wand vaporizer on the market and is water dunkable to cool it down between vaporizations.


I started off with the Varrox which worked well but with larger numbers of hives takes a long time. I purchased 2 ProVaps from Larry and use them during Winter on an as needed basis as well as will be rotating OAV with thermal treatment. Both the Varrox and the ProVap are excellent products as is Larry's patient customer support!


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## little_john (Aug 4, 2014)

Plannerwgp said:


> I am always interested in the discussions regarding Oxalic Acid treatment and wonder how individuals using this chemical protect themselves from the dangers associated with the use of it. I was about to purchase a vaporizer and then read the warning labels regarding OA and decided I would prefer to protect my health over that of the bees. I am currently looking for other treatments that may be less damaging to my health. The use of OA does require a respirator, protective clothing and gloves. That sort of tells you that you're dealing with a serious chemical that may damage your health if you don't properly protect yourself. I hope you all protect yourself, and read the labels before using.


You only need Personal Protection Equipment if you 'get up close and personal' to the hive being treated. If you operate the dosing equipment from a modest distance away - and upwind of the hive - then you don't need to take any precautions.
LJ


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## snl (Nov 20, 2009)

little_john said:


> You only need Personal Protection Equipment if you 'get up close and personal' to the hive being treated. If you operate the dosing equipment from a modest distance away - and upwind of the hive - then you don't need to take any precautions.
> LJ


ABSOLUTELY NOT TRUE! A shift in the wind could have you breathing a lung full that you’ll take to your grave with you. A full face respirator is best as it protects lungs and eyes. That said, wearing protective gear makes using OA very safe. We use masks for lots of duties from cutting the grass to spray painting. It’s no more than a slight inconvenience.


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## snl (Nov 20, 2009)

*How I treat and what works for me

When I pull my honey supers after the nectar flow has ended but no later than late July, early August, I begin an OAV treatment regimen. Why? Because, for me, at that time, the mites are either just beginning or are already outbreeding the bees. Since OAV only kills phoretic mites (not mites in brood under cappings) you need to do multiple treatments to kill those mites that were in those capped cells during the treatments and will emerge with the brood. You need the OAV treatment to cover that emerging brood cycle. A regimen of treating every 7[SUP]th[/SUP]
 day for 3 weeks is ok for many. Better yet is a treatment every 5[SUP]th [/SUP]day for 4 weeks. Outstanding is a treatment of every 5[SUP]th[/SUP]day for 5 weeks.


A 1% infestation based on a wash or sugar roll in mid- July left unchecked, is a dead hive in October or November, they just don’t know it yet.

You may say some of those regimes don’t cover the brood cycle. You’d be correct ​IF OA only killed on day of treatment. However, OA has a lingering effect. OA will continue to kill until the bees (who see the OA crystals as trash) carry them out. Studies have shown that OA resides in the hive for + -3 days when bees are flying. OA lasts and kills mites much longer if applied in cooler weather when the bees are not flying to carry the OA crystals out.

Mites do not immediately emerge with brood and re-enter a cell about to be capped to breed. They remain phoretic 4-14 days. During this time, they get their hair curled and nails painted in preparation for breeding! Not really, this time of the mites outside the cell gives an OAV treatment the opportunity to destroy them in a phoretic stage. Once you’ve completed the treatment regimen you need to test that it was effective enough. A single OAV treatment within days (maybe 5-7) after your last OAV treatment (this time with a sticky board) will show all you need to know after looking at the resulting mite drop. If that mite drop is heavy, you need to continue with OAV treatments until the mite drop is extremely low. 


A question you might ask....

Why, when I did my sticky board test, am I (if you are) still seeing a high mite count? Didn’t OAV work? A mite coming into contact with OA will die. That’s a known fact. So why are you possibly still seeing a high mite drop? 



Two very probable answers. 
​

Drift from untreated hives and
(which is really a part of answer 1 and is what Randy Oliver and others call “mite bombs.”



What are MB’s? They are collapsing nearby hives. Your bees are raiding them for honey stores (thus picking up and bringing back mites) AND/OR the bees from the collapsing hive(s) are absconding from their dying, mite infested hive and entering yours with mites attached. Unfortunately, neither of these events can you control. Thus if in your test, you see a heavy mite count, continue to treat. 
Ok, you’ve treated until you have a very low mite count. Now what?

You do ​another treatment in very late autumn or early winter when your hive is at its lowest brood point. Studies have shown treating one time at this time when all or almost all the mites are phoretic (since there is no brood for mites to enter and breed) will kill an astounding 97% or better of ALL the mites in the hive! Why not 100%. There are always those mites that manage to avoid coming into contact with OA. 

Ok, now what? You’ve this basically mite free hive. The NEXT treatment is what I call my “feel good treatment.” In spring, with a great queen and tons of bees and brood ready to collect nature’s bounty and right before I place my supers, I do my “feel good treatment.” It’s a one OAV shot, that just makes me feel good that I’ve done all that I can to keep my mite count on bees low. 

This OAV schedule works for me and OA is all I use to control mites. The key is multiple treatments and doing them timely. You miss a day or days during a multiple treatment regimen, you’re giving mites the opportunity to enter cells about to be capped to breed. 

If you’ve not treated at all, have a full hive & are just now purchasing a vaporizer. Start NOW with a 5 or 7 day regimen. (Remember, per the EPA, you cannot treat with the supers on.) If you’ve supers in place either remove them for the treatment (replace 10 minutes thereafter) or place some newspaper between the brood chamber and supers. You need not remove the newspaper as the bees will discard it for you!

If you’ve just purchased a package, best practice is to hive it and vaporize one time when you see eggs/larvae but ​before the cells are capped! That’ll kill the phoretic mites and you’ll have a “mite free” hive to start.

​*


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## little_john (Aug 4, 2014)

snl said:


> ABSOLUTELY NOT TRUE! A shift in the wind could have you breathing a lung full that you’ll take to your grave with you. A full face respirator is best as it protects lungs and eyes. That said, wearing protective gear makes using OA very safe. We use masks for lots of duties from cutting the grass to spray painting. It’s no more than a slight inconvenience.


Some of us have been using VOA since before most of you guys ever heard of it. Are you seriously telling me that if the operator is standing 30 feet away - or 60 feet away - then they're still at risk ? The devices you sell are the 'up close and personal' bits of kit I was referring to. I don't use those.
LJ

By the way - you can't take a lungful - it's impossible.


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## snl (Nov 20, 2009)

Lj,
To each his own. I just don’t think it’s wise to promote (especially to those who are not experienced) using a product that could cause harm without protection. A few simple precautions never hurt.


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## Lburou (May 13, 2012)

dphillipm said:


> ...1st the powder turns to a liquid then boils off into a vapor. At what point does the acid turn into a useless vapor that doesn’t kill the mites? ...


THIS Video answers your questions about temperatures and oxalic acid. 373 degrees F is the point that OA vaporizes into formic acid and CO2. HTH


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## johno (Dec 4, 2011)

Gone are the days when most folks were reared to have a little common sense, most of the folks talking about this dangerous materiel had better not go swimming cause the water that you guys are going to breathe in is surely going to do you in. On the other hand I always wear my mask, a paper 3M 8511 when I am treating my hives inside of a closed room so there you are. Dangerous stuff indeed if you are accident prone or downright negligent, I was thinking of saying stupid but what kind of folks play with insects that sting the crap out of you so I will withdraw that word.


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## JWPalmer (May 1, 2017)

I may be just a little on the crazy side because I enjoy going out to play with nearly a million stinging insects in my backyard. But, I am not crazy enough to use my Provap110 without a mask. Well, ok, I was stupid enough to try it once.


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## dudelt (Mar 18, 2013)

When I first got my vaporizer, I did not use a respirator. I would stand far from the hives and when I did go to pull the vaporizer out of the hive, to be safe I would hold my breath. Once I got my first whiff, I immediately went on amazon and bought the respirator. PLEASE... learn from my mistake and use one. 

As far as the treatment schedule goes, what works here, may not work for you. I treat 4 times, 5 days apart starting the first week in August. I then treat once the first or second week in December. That is it. I had only one loss last winter and no losses this winter.


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## ifixoldhouses (Feb 27, 2019)

How does dipping it in water hurt it? I got one for $69 http://www.blueridgebeecompany.com/store/p1/Oxalic_Acid_Vaporizer.html
and dipping it in water hasn't hurt it yet, done it 10+ times now I guess.


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## johno (Dec 4, 2011)

There is more to the OA story than the video Lburou put up. First of all if there was not a water molecule locked into the OA I doubt that you would have a Provap or Easy Vap. It is the boiling off of this water that creates the pressure that forces out the OA vapor which condenses as it leaves the outlet. One can talk about temperatures all you like but the surface temperature where the boiling off and sublimation takes place is a skin temperature and is probably much lower than the temperature shown by the thermocouple. the thicker the bottom of the bowl is the higher will be the difference in actual to measured temperature. Furthermore Latent heat plays a major factor here as you actually get chemicals that have locked in water mlecules that are used as flame retardentd as when that molecule boils off it cools the surface of the chemical and tends to slow down combustion, so my guess is that the boiling off of the water in OA tends to cool the OA to some degree.


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## username00101 (Apr 17, 2019)

Can someone link to the correct respirator to use via amazon?

What about eye protection, if I have glasses is that good enough?


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## SeaCucumber (Jun 5, 2014)

Any advice on dose (per medium box), round duration, interval time, times of year, or heating hives would help.

http://www.bushfarms.com/beesmath.htm

With limited clinical research, here is what I am considering for the treatment variables. 

round duration:

According to the above link, the maximum time for a bee to live in a cell is 25 days. In winter, its 21 days. Ignoring immigrants, if the treat round starts and ends >25 days apart (>21 in winter), all mites should be treated.
Can the first dose kill mites in eggs and larvae? If yes, a shorter duration to cover the pupal stage makes sense. Is a stronger first dose needed for this?
I don't know what the minimum frequency should be. 
This data should help:

the time from egg laid to when the mite is likely to enter the larvae
the lifespan of a treatment
Heating hives: I have screened bottom boards. According to my hardiness zone, the yearly low temp averages -5 to 0 deg. F. I could put a heater between the screen and drawer and heat to a certain temp with the goal of loosening the cluster before winter treatment.

my beliefs: 

TF (treatment free) beekeeping is ideal.
Ideal queens come from TF colonies.
Production yards should estimate their mite levels and treat all or none of the hives because counts for each hive takes too long. 
Queens should be blamed, so treated hives should be requeened.
Treatments should be: 
- low in frequency, but enough to meet thresholds
- thorough with few survivors
- not breeding tough mites

my goal: To breed TF queens

plans:

I don't trust my 3 hives right now. I treated them once in spring. I plan to do a round of treatments before winter, and either 1 treatment or a round in winter. 
Get TF queens to breed from next spring.
Have a mating yard.
Estimate average mites/colony for the whole yard, as well as a relative count for every colony.
Higher count hives will get shunned. Shunned hives will get more treatments, and will not be grafted from until they are requeened (unshunned).
Hopefully I will have some TF colonies next year and only have to treat shunned hives in winter.
to someday have a TF yard


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## SeaCucumber (Jun 5, 2014)

It might be time to treat, so any other info would help.


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## dudelt (Mar 18, 2013)

username00101 said:


> Can someone link to the correct respirator to use via amazon?
> 
> What about eye protection, if I have glasses is that good enough?


I use a "3M Safety 142-5303 Safety Half Facepiece Disposable Respirator Assembly, Organic Vapor/Acid Gas, Large" Search on Amazon for that and you will be just fine. I use standard safety glasses over my regular glasses.


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## dudelt (Mar 18, 2013)

SeaCucumber, 

Can the first dose kill mites in eggs and larvae? Mites do not bother with eggs and only hook up with the larvae just before it gets capped.

Drone cells are capped for about 14 days which is the longest period of all bee types. For summer and fall treatments the first treatment will kill most of the mites walking around the hive. The second treatment 5 days later will kill most of the mites that hatched from the cells over the last 5 days. The third treatment, 10 days after the first one, will kill most of the mites that hatched out over the previous 5 days. Finally, the fourth treatment 15 days after the first one, will kill most of the mites that hatched out over the previous 5 days. That covers all the mites that needed to be treated. If you hive is not raising drones, 3 treatment should work just fine for you.


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## SeaCucumber (Jun 5, 2014)

I saw some deformed wings. I am going to start treatments tonight (day 0). I will treat on days 0, 2, 7, and 12. msl's link puts the dose at 1 to 3 g. All my hives have 3 mediums. 

Not counting this round, I will do 2 treatment rounds between now and next spring. I need to pick a date for the next one. With respect to average daily high temperatures, when should that round of 3 or 4 treatments be? The last one will be 1 treatment around the coldest day of the year.

idea for commercial treatment:
Use a fancy power supply. This device turns your vaporizers on and off based on a time interval that you can change. Use a lot of cheap vaporizers. Vaporizers are hooked up like so: power supply, extension cord, light and button switch, vaporizer. You insert a vaporizer and press the button. The red light turns on while the vaporizer is on. You keep loading and running vaporizers. There is no down time. When your last one is in, the first is ready.


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## JWPalmer (May 1, 2017)

SeaCucumber said:


> Not counting this round, I will do 2 treatment rounds between now and next spring. I need to pick a date for the next one. With respect to average daily high temperatures, when should that round of 3 or 4 treatments be? The last one will be 1 treatment around the coldest day of the year.


The number of OAV treatments is based on mite load, not a pre-determined idea, unless you are going to calendar treat. I calendar treat because I already know when my mite loads are likely to spike. If that is the case, you probably are missing a treatment round or two. I just started treating last week. Most of the hives had very low initial drops, 3 or 4, but at least one hive dropped over 50. That means everyone get another dose tomorrow. What works where I am is full rounds in August, September, and October. Single treatments on Thanksgiving and Christmas. My state inspection had me at 0 mites in March.

For me, a single ProVap110 will treat the hives about as fast as I can measure out the OA crystals. Johno's Easy Vape should go just as fast and is less expensive.


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## jeetS (Jun 7, 2019)

JWPalmer said:


> The number of OAV treatments is based on mite load, not a pre-determined idea, unless you are going to calendar treat. I calendar treat because I already know when my mite loads are likely to spike. If that is the case, you probably are missing a treatment round or two. I just started treating last week. Most of the hives had very low initial drops, 3 or 4, but at least one hive dropped over 50. That means everyone get another dose tomorrow. What works where I am is full rounds in August, September, and October. Single treatments on Thanksgiving and Christmas. My state inspection had me at 0 mites in March.
> 
> For me, a single ProVap110 will treat the hives about as fast as I can measure out the OA crystals. Johno's Easy Vape should go just as fast and is less expensive.


I just did my three largest colonies...the rest are newer splits that haven't had brood in them for long... the three largest had a drop of 1, 3, and 15... Would the 15 count give you cause for concern?

This is my first time trying oav, I lost a queen to formic last year


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## JWPalmer (May 1, 2017)

Hi jeetS, welcome to Beesource. My personal threshold for continuing the early summer round is 20 mites or more in any of the hives. I checked 5 of 22 before I had a high enough drop to warrant the additional applications. Given that roughly 20% of the total mite load is phoretic at any time, a drop of 50 means I had at least 400 mites in that hive. With a drop of 15, I would probably wait another two weeks and do a single application again. If the numbers stay high, do a full round, and treat the splits too.


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## jeetS (Jun 7, 2019)

JWPalmer said:


> Hi jeetS, welcome to Beesource. My personal threshold for continuing the early summer round is 20 mites or more in any of the hives. I checked 5 of 22 before I had a high enough drop to warrant the additional applications. Given that roughly 20% of the total mite load is phoretic at any time, a drop of 50 means I had at least 400 mites in that hive. With a drop of 15, I would probably wait another two weeks and do a single application again. If the numbers stay high, do a full round, and treat the splits too.


Awesome thanks! Exactly what I was looking for.

The three I did were all double deep brood nests.
Do you just separate the Honey for the treatment time with your early summer treatments?


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## JWPalmer (May 1, 2017)

jeetS said:


> Do you just separate the Honey for the treatment time with your early summer treatments?


Where I live, the honey supers are off for the season. You can remove the boxes temporarily, or stick something like a sheet of corroplast (political sign) underneath while treating. Only need 15 minutes for the aerosol crystals to settle down according to what I have read.


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## jeetS (Jun 7, 2019)

JWPalmer said:


> Where I live, the honey supers are off for the season. You can remove the boxes temporarily, or stick something like a sheet of corroplast (political sign) underneath while treating. Only need 15 minutes for the aerosol crystals to settle down according to what I have read.


Okay thanks &#55357;&#56397; that's what I did


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## SteveHive (Apr 24, 2017)

Anybody has experience with this? need some advice before spending money !

https://www.youtube.com/results?search_query=oxalika+pro


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