"And after all that, effectiveness has very little to do with temperature and a lot more to do with dosage.
https://blogs.ifas.ufl.edu/entnemdept/2021/12/09/research-update-determining-the-dose-of-oxalic-acid-applied-via-vaporization-needed-for-the-control-of-the-honey-bee-apis-mellifera-pest-varroa-destructor/"
Thanks for posting that link Beesnweeds. I also agree with dosage, as well as when to administer that dosage, (but also along with heat ).
In fact Dr Cameron Jack, the main fellow in your report, (and there were some heavy hitters listed on the bottom of that report), had already let me in on that information, months before your article came into print and was made public by the University of Florida.. In fact I posted the very reveling letter which he wrote to me, and with his permission I posted it here at Beemaster for the benefit of you all here...
Varroa checksMark I had this basic discussion with Cameron Jack, related to his thoughts of 4 g instead of 1 or 2, as discussed here in in the first part of your video. I got in touch with him after several of us here at Beemaster were having a discussion, some time ago, on the topic: "OAV too hot?"
After watching part 2, the video that you posted, studying his chart, I am sustained in my confidence that Coolbees is on target with his 3 day / 9 treatment program.
We shall in time, see about the OAV strips mentioned here as the study progresses? I hope they work!
Beesnweeds if you recall, you and I have discussed dosage some time back but I appreciate your posting for the benefit of our new members as well as our friends in Australia as they are at ground zero concerning Varroa Destructor.
Back before it was widely know that the approved 1 gram was not effective enough. I shared with 'you all' here the private correspondence between Dr//Researcher Cameron Jack (with his permission of course) not of just of the 2 grams that you mentioned then, but of the 4 grams...
Varroa Check >Spin-off<A recent study out of the University of Florida showed no ill effects of increasing from 1 gram to 2 grams of OA per brood box. They did see an increase in efficacy. I dont know if they will try and have the label changed to 2 grams or not. Personally I never witnessed any observable ill effects to brood using 1 gram.
beesnweeds I feel sure they plan to present the label change request to the EPA. As I received the following correspondence form Cameron Jack April 2020. I do not know if the request has been placed as of yet and if so, if it has been approved.
Good morning Phillip,
I don't mind you sharing our conversation on a bee forum. I would say that the current legal limit of vaporizing 1 g is totally worthless. I don't necessarily mean that OA vaporization is a bust, because you start see some control at 2 g and a slightly better effect at 4 g. To be clear though, even after three rounds of treatment at 4 g once per week, we still had average mite loads of about 2 mites/100 bees. We started with high loads, so it did knock it down significantly, but we didn't see the efficacy you would expect from something like amitraz. However, with resistance issues cropping up with amitraz, it is important to have a few more weapons in our arsenal. All that said, I am not recommending anything, just telling you our research findings. As I said earlier, we do plan to take our research to the EPA to advocate for a label change.
At this time, we are probably still getting our best control with amitraz, though we are starting to have some resistance issues ourselves. Thus, we use OA via trickle and vaporization during the winter and early spring. In Florida we don't have much of a spring and jump quickly into summer, so if we still need a treatment in the spring before the nectar flows, we use thymol.
We really do try to practice what we preach and we use alcohol washes to sample our apiaries at least every other month to monitor Varroa populations. I feel strongly that frequent monitoring is a critical practice these days, especially after treatment, so you know if what you've applied is even working for you.
Best,Cameron
Cameron Jack, Ph.D.
Lecturer and Distance Education CoordinatorEntomology and Nematology Department
University of Florida
PO Box 110620
1881 Natural Area Drive
Gainesville, FL, 32611
Topic: Thoughts on This Veroa Treatment? (Read 1497 times)