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Multiple OA Vap treatments

5270 Views 27 Replies 16 Participants Last post by  mtnmyke
Turns out my mite control early in the year was not as effective as expected, so I have one hive with an excessive mite load. This is my second year as a beek, so still dialing in how to be a beekeeper rather than a varroa mite keeper. I did a full course of OA vaporization over the last two weeks (3 vaporizations) but my sticky board is still showing ~40 mites per day.

I am debating doing another course of OA vaporization; do some of you more experienced folks out there think that's a good/bad idea? Any other recommendations?
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I dont think another round will hurt them. I have had several hives that I treated with OAV once a week for 6 weeks due to problems when I was available and mite loads.

edit: remove math because I got layed and capped days mixed up
Check your bee math🤔 If drones are the preferred host for mites and pupate beyond 21 days, how could 3 rounds be a complete treatment?
I treat every 5 days for 5-7 applications of oa. I'm only going to stop when I see 1-2 mites drop in 24 hours after the last treatment.
The mites have a thirteen day breeding cycle. Three more treatments wouldnt hurt.
Check your bee math�� If drones are the preferred host for mites and pupate beyond 21 days, how could 3 rounds be a complete treatment?
I treat every 5 days for 5-7 applications of oa. I'm only going to stop when I see 1-2 mites drop in 24 hours after the last treatment.
Yes!

I think the number of days under cappings is the controlling factor. I think most suggested durations extend to either side of that time frame, but I am convinced though that very little effectiveness of each single vaporization exceeds three days. The emerging mites utilize these treatment holidays to nip back into cells newly vacated! I smoke every 4 days and if weather is iffy, I will choose to go 3 days rather than 5 for the next treatment.

I dont sign any contract to only do battle for a set number of days! I continue individual repetitions till there are no more mites dropping.
Oh, wow, ok, I didn't realize you can just maintain the vaping for that long. Great! That will hopefully help them along...
Here is a list of the time it takes for each bee stage from laying

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

Drones are capped for 14ish days, so you are right on the edges for getting all of the mites with a treatment if you are using a 2 week cycle.
Keep hitting them until mite drop reaches 1 or 2. I have done as many as 12 treatments, with no apparent ill effect.
This is exactly what I'm seeing Crofter. On day two I'm not even seeing half of the drop I saw on day one. Hit them on day three and the drops are close to what I see on day one.
On a side note I had watched a presentation by a young lady on the National Honey Show. I'm pretty sure she said a mite spends up to six days maturing before reentering a cell to breed. I'm going to have to watch it again to see if my memory is correct. Getting old is getting old....
The offspring may spend six days to mature before they enter a cell to reproduce. The foundress(mother) mite can/will re-enter a cell shortly after leaving the cell that is opened by the emerging bee.

I am surprised there has been no discussion about acid treatments in light of Jerry Hayes answer to question on NY Wellness video. He is a well respected and is strongly opposed to acid treatments, oxalic and formic treatments.

https://www.youtube.com/watch?v=bF1Uhldw1KY&feature=youtu.be

Time of question is 1:00:32

I am going to pay more attention to how many times I treat(only when needed) and be more careful with recommended dosage. Is there a correlation between queen's useful life and acid treatments????? I know my experience with queens is a useful life of about a year.
He seems to be using scary analogy to support a hypothesis. No studies are mentioned to support the claims of damage to the queens. Some other bee gurus for a while were using the quite possible damage from drizzle applications and assuming suggestively that the same was true for vaporized OA.

This bears further scrutiny but there are some reports of having done very closely spaced OA vaporizations continually for months with no apparent damage.
While Jerry's comments fit well in my world view(OA over use is bad) making them attractive, But I haven't seen a single a study to back his statements about queen damage

When compared to formic and thymol's well documented impact on queens the results with OA have been more or less nonexistent.

Could it be something to do with him being the North American VP of Vita Bee Health? The makers of Apiguard:scratch:

https://www.vita-europe.com/beehealth/news/jerryhayes/
:thumbsup: I do a dead drop count and plot results. You can see the peak and rate ( robbing induced) of decline. This typically results in a treatment every 4 to 6 days. Winter treatment: I do 2x, 14 days apart to verify the house cleaning.
Treatments are bad.

I did a round of 5 treatments 5 days apart ending 7/19. That was to prepare 2 hives for being treatment free with TF queens that arrived the next week. I didn't count drops well, but the 20 day average was ~8 mites/hive. Last year at that time, it might have been thousands. Last year's OAV must have worked well.

I'm considering doing 1 treatment this fall. This one doesn't need to be great. The winter broodless one will be strong. Assume I open feed 1 big serving at time 0. It should be eaten in 2 days. We will call brood made because of the feed induced increase "new brood", and assume they are laid at time 0. The treatment should be before the mites can use the new brood. It should also get mites from robbers. 2 or 3 days after time 0, the new brood will be eggs. That might be a good OAV time.
I dont think your brood rearing predictions cannot be anywhere near that well defined. Robbing of other hives by your bees may continue.

Generally it seems like a good process to get the mite counts to very low levels. It is always good to verify. Some mite bomb situations seem almost to defy explanation.
I stopped worrying about the number of days drones are capped years ago. By the time I start my first round of OAV, usually the first week of August, there is very little (if any) drone brood in my hives. Our annual drought convinces the bees to stop rearing lots of drones fairy early. If I am still seeing a large drop in mites after the last scheduled treatment, they will get another until the large mite drops are done.
Hello,

Continuity from start to finish on OA treatment is the most important issue. I do 6 treatments on my double deep with 3 gram each time from the back 4 days apart. Always in the evening dusk.

I still have one super on and will extract my last and best honey on the 25th of September. I still have borage flowering, even after -1°C and many other plants are still flowering in my region well in to October.

My mite treatment does not start until mid October. I do wash tests in May & late August and my August drops where 1-2/100.

JoergK.
Jerry Hayes worked for a couple of years with Monsanto/Bayer and then joined Vita Bee Health in 2018. In 2019 he was named the new Editor of Bee Culture. He replaced Kim Flottum. I guess I thought he had resigned from Vita Bee Health at that time, but I do not know that. I certainly think there would be a conflict in doing both, but maybe not.

Jerry has repeated his refrain for many years regarding the harms of OA on bees. He has stated that there are studies out there that bare this out. I have a hard time believing Jerry is outright lying to us. I think he might be reading things into studies that others do not. But he certainly has many platforms (especially now as editor of Bee Culture) to demonstrate his claims. He has been challenged on it many times. Until Jerry places the evidence in front of us, I will continue to respectfully disregard his claims.

I have a lot of respect for Jerry Hayes. He is no kook. My mind is still open, but he needs to show me something on this one.
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Turns out my mite control early in the year was not as effective as expected, so I have one hive with an excessive mite load. This is my second year as a beek, so still dialing in how to be a beekeeper rather than a varroa mite keeper. I did a full course of OA vaporization over the last two weeks (3 vaporizations) but my sticky board is still showing ~40 mites per day.

I am debating doing another course of OA vaporization; do some of you more experienced folks out there think that's a good/bad idea? Any other recommendations?
I am assuming in San Diego, CA that you have year-round brooding? If so, it is much more difficult to control mite load in these conditions than in those that actually have a natural winter respite from brooding. You may need to try another treatment such as Apivar, thymol or formic.
Yes, no real brood break here... I have been thinking about caging the queen to generate an artificial brood break. It would increase the effectiveness of the treatment, but I am also concerned about reducing the population in a hive that is already struggling due to the high mite load.

I hadn't considered the effect of robbing. The hive with the high mite load did have a robbing attack that I had to stop with some strategically placed garden hose spraying. Correlation isn't causation, but it is an interesting coincidence.

One area of differing opinion seems to be the number of day's between treatments. I've been using 5 days primarily; since the maturity cycle is 7 days, what benefit is there to going more frequently?

I am assuming in San Diego, CA that you have year-round brooding? If so, it is much more difficult to control mite load in these conditions than in those that actually have a natural winter respite from brooding. You may need to try another treatment such as Apivar, thymol or formic.
I am chomping at the bit to use my FormicPro pads; trouble of living in San Diego is that the temperatures are still in the 80s and 90s there days...
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