I was not quoting him, and i am far from being negative towards the oxalic/clycerin treatment. On the contrary. I just cant stand the way certain people handle any criticism and questions towards it. That doesnt mean they generally do a bad job at helping to develop a new treatment.
Youll be there too as soon as synthetics stop to work, which they will eventually if you assume the situation here develops similar to Europe. Then the mite levels that the bees can withstand will become lower over time as the mites seem to be becoming more virulent. That will pretty much mean that heaps of hives die over winter despite being "properly" treated like every other year. Also the influence of pesticides towards the tolerance towards mites is something that is just starting to be examined.
That said i consider myself to be far from an expert and no need to bow before me. Im just very interested in everything beekeeping related! What I know from whatever source ill happyly share.
Ill try to elaborate here: again take everything with a grain of salt there certainly are people out there that know waaaaay more than me !!!
What i personally consider the most important tool for Varroa Management is regular checking of mite levels either via alcohol wash or sticky board. Randy Oliver advertises the alcohol wash method even though he is managing thousands of hives. So he mast have found a way for him to do it fairly quickly...
Just waiting for any signs with the brood pattern or deformed wings will mean by the time you see somethings wrong it will already be (too) late...
I personally would advise meshed bottom boards with sticky boards underneath (they actually dont have to be sticky, a piece of corflute will do a fine job). That will let you very quickly assess the mite situation in any apiary within minutes. However it may require building new bottom boards. I personally think that open bottom boards are beneficial for standard langstroth hives anyway (and top insulation!). You dont need to worry that the bees will be too cold in winter, they'll even survive temeratures up to -15C just fine. And in summer you have better ventilation and less bearding (in my limited experience) Also you can keep entrances reasonably small even during smouldering hot days and wont have to worry about ventilation which helps against robbery. Also (and that is unproven but I would assume it would be this way) with an open bottom board you might "persuade" a hive even in warmer tempered regions to stop rearing brood for a few weeks during winter which would be a huge benefit to get rid of a lot of mites.
Also with sticky boards (and mite washs) you actually dont have to count the mites... Depending of the time of the year and the stat of the hives all you need to know is if there are none/very few/too many or waaaay to many mites in there.
What i learned doing regular mite checks is that although an apiary can have quite low infestation levels there will always be outliers with heavier infestations and that in late autumn mite levels can suddenly increase again seemingly out of nowhere...
Both Formic Acid and Oxalic Acid would be suitable and are widely used in Europe.
lets start with FA:
Huge advantage of FA is that it will even kill mites INSIDE capped cells if the dosage is right.
Generally FA is a very tough treatment to any hive, expect all open brood to die. Also the dosage (ov FA vapour inside the hive) must reach a certain level (so it is efficient enough, but not much higher (or it will kill/harm the hive). Sadly the amount of evaporation of FA is dependent on the temperature and humidity. You cant use it if its too cold or too hot...
I have used the Nassenheider and while i think its a very good product for hobbyists i dont think its suitable for commercials. Just too fiddly and too much work involved. (did you know you should check the amount that has evaporated within the first 24 hours? those small wicks apparently have quite a high deviation.
MAQS seem to work very well (even in lower temperatures) and would probably be suitable for commercials, but at a fairly high price. By the way i certainly wouldnt put them into any hive with the honey supers on.
What the Germans did in the early days of FA treatment is to dribble a small amount of it onto a cleaning sponge and put that on the frames (kind of like a homebrew maq) the FA will evaporate fairly quickly though and youll have to do multiple "shock treatments" Again probably too labour intense.
Now towards Oxalic Acid (OA)
scientifially as far as i know it is still unknown how OA kills mites, however it is believed that mites walking over tiny OA crystals evenly spread inside a hive will kill them. BUT it will only kill phoretic mites.
as of now there are 4 ways to get OA crystals into a hive.
- dribbling: you basically Dribble an OA (3.5%)-Sugar-Water solution onto the bees, ideally while it is cold. The bees cleaning themselves will spread the OA. This is the most common winter treatment in Germany (when the bees are free of capped brood) and under that circumstance works very well. however it is the most harmful OA treatment. As it is very quick to do it would be very suitable for any commercial. In Germany it is believed that you only can do such a treatment once in winter (which is a problem if they still have capped brood left)
- spraying: you spray OA solution (2.5 - 3.5%) onto both sides of every frame. The sprayer must create a very fine mist. The water evaporates and leaves the tiny little OA crystals. As they are dry and there is no sugar the bees dont seem to ingest any OA thus it is very gentle on them (not so gentle if you have a lung - wear a mask). From there the result is very similar to OA vaporization just waaaay more labour intense and certainly not suitable for anybode with a lot of hives. For any hobbyist its a great alternative to buying an expensive vaporizer though.
- vaporization: You heat up OA, it vaporizes and then quickly resublimates creating a finely dispersed dust in the air. that dust has to be spread in a hive, either with a fan or by the expansive force of the sublimation itself. In my opinion currently the best treatment. The soviets already treated their hives with this method and the mites in Europe still arent resistant to OA. You can basically do it as often as you want without harming the bees. There are many commericals in Europe that use this method, provided you have a good vaporizer this will work quickly enough. Still quite labour intense but doable. If there is capped brood youll have to do it multiple times. Randy Oliver did write a fairly good article about it explaining the basics and the mathematics.
- OA strips: the bees walk over the strips, chew them, try to remove them whatever, which again is supposed to spread the oa inside the hive. Seems to be a very elegant method, however many unknowns as of now (which will hopefully be resolved in the near future thanks to scientists and philbees 🙂 ) certainly suitable for commercials and seems to work most of the time. However Id personally ask what effects the Glycerine might have and if there are any residues to be expected. Also elevated bee mortalities seem to be an issue sometimes, and it is unknown as to why that is the case.
Its the newest application method for OA and thus there are many unknowns, that doesnt make it a bad treatment. But rest assured it certainly wont be the magic solution to all your mite problems. it certainly will generate a good income for some that manage to create a seeable product (and that is fair enough and well deserved in my opinion)
What is becoming more and more common in Germany by the way are biotechnological methods. Especially in Summer after the honey harvest or 2 weeks before its end you can remove all capped brood and either make a lot of nucs or simly melt all frames (and kill the bees and most mites). Then you do 1 or 2 OA treatments (spray or vape) and thats your mite problem sorted. unless you have reinfestation in late autumn. The hives will quickly bounce back and generally overwinter very well. Also its a good chance to get any old comb out of the hives (old comb and the pollen stored there might be contaminated with pesticides). if you make nucs out of the capped brood you theoretically could double your hive numbers every year (imagine doing that while hives where ridiculously expensive a couple of years ago). If they raise their own emergency queen (or recieve a cell) there will be a window of a few days where they have no capped brood. thats when you should treat them. Again likely be waaaay to labour intense for you!
So i do think that for a 600 hive set up sticky boards, MAQS, and OA vaporization (and strips in the not too distant future!) might be a way to go. Maybe still stocking some synthetics just in case? Of course it all depends on local circumstances and climate.
the german law and best practice has been that you only can treat for varroa when the honey supers are off (and are not being put on again afterwards) and your treatment has to be before 31st of January each year (for you sourthern hemispherans that means in the midst of winter 🙂 ) So no spring treatments. When there is a brood break during winter you actually get away with it.
recently MAQs and a few other products became certified to be used either with supers on or only a few days before supers are being put on. I do not think that that is a good approach towards selling a pure and healthy product (honey)