Do a search for a thread from 2005 called "oxalic acid in a fogger", gives mixture ratios https://www.beesource.com/forums/show...ID-IN-A-FOGGER
"SERENITY is realizing that the bees know what they are doing, even when you don't..."--thenance007
Can't go in the details. I might be selling these strips soon.
Anthony, I will give you a call once we go through round number 2. Know of any beekeepers that have mite infested bees? My bees are low on mites to begin with.
I don't have any now but may this fall... I would be interested to learn more. Are you making them?
Last edited by newred; 05-22-2016 at 12:50 AM.
What I like is that this gives alternative 'recipes' that hopefully help in decreasing the varroa building up resistance to using the same OA cocktail all the time.
It's not humour.
It just works.
Varoa becoming resistant to OA is like a roach becoming resistant to being stomped on
For the mites to become resistant, OA would have to be poisonous to them. It is not. My understanding is that it dissolves their feet and they essentially bleed out. Can't cite a source for that though.
Thankfully, the bees are smarter than I am. They are doing well, in spite of my efforts to help them.
While the internet is full of such legends, the work on it is showing outher wize
Toufailia ET AL 2018 Towards integrated control of varroa: 4) varroa mortality from treating broodless winter colonies twice with oxalic acid via sublimation
2nd broodless OAV killed about 35% less mites
"combined varroa mortality was very high, 99.4%, with greater mortality from the first, 98.3%, than the second, 64.1%, application"
so for what ever reason, Resistance can and does happen... weather or not its inheritable may be another story.
Here is a fogger video with mixing instructions.
I don’t think you can “dose” with any accuracy using these forgers. Does dosing matter?
Last edited by Andhors; 08-05-2019 at 10:42 AM.
If resistance was considered to have occurred, then I'm sure the authors would have highlighted this - instead they concluded:
The double application being referred to of course, being performed during an 'essentially broodless' winter period.Overall, the results indicate that double application of OA is worthwhile to beekeepers in varroa management. It is not harmful to colonies and by killing c. 99.5% of the varroa it reduces varroa populations to such an extent that 7–8 doublings, which would take more than one year, are needed to build back to the original level.
Since writing the above, I've managed to track down the original work - which was a PhD thesis submitted to the University of Sussex (UK): https://core.ac.uk/download/pdf/42579622.pdf
Regarding the lower figure from the 2nd treatment, the author writes:
Quite a few options there to choose from.Varroa mortality from the second OA treatment was lower than in the first, 87.2 v 96.8%. This difference is significant (P<0.001). We do not know why the second application was less effective than the first although there are several possibilities. One possible explanation, which would merit further research, is that some varroa are genetically resistant to OA. However, some mites may be less affected due to phenotypic differences that are non-genetic, such as due to age (Kirrane et al, 2012). It is possible that some mites consistently chose more protected phoretic locations on a host bee, or remain on a single host bee that is less contacted by the oxalic acid fumes perhaps because it consistently remains in a location that receives a lower dose of oxalic acid fumes. The final possibility would require that mites remain on the same host bee across the 2 week treatment period. There are currently no data on how frequently phoretic varroa mites change their host bee in broodless colonies, or whether particular bees may consistently be located in parts of the hive more or less contactable by OA fumes from sublimation.
as I ended with
Were I was going was when some one says "this is OA's mode of action" or "resistance to OA can't happen" they are in the relm of specuation, not sisistific factResistance can and does happen... weather or not its inheritable may be another story.
I think I may have a explanation for the second (lower percentage) figures. In the introduction to this guy's thesis - which is crammed full of useful info, btw, and well-worth reading - he writes:
Chapter 8: Towards integrated control of varroa: Monitoring honey bee brood rearing in winter and the proportion of varroa in small patches of sealed cells.
This shows that December is the month with the least brood. However, winter reduction in brood rearing varied among years and even in December some colonies still had sealed brood. Although the amounts of sealed brood were low, even a small patch of c. 500-600 sealed cells could contain 14% of the varroa in a colony.Now the assessments of the effectiveness of OA vapourisation (i.e. the kill rate) were made 2 weeks after each application, and so during this 2 weeks at least some of that brood will have emerged - along with any live varroa mites which will have been hidden and thus protected within those brood cells.The amount of sealed brood in December 2015 was particularly high, both in the proportion of colonies with sealed brood (52%) and in the number of sealed brood cells (mean = 788 ± 336) in the colonies with brood. This was almost certainly due to the warm conditions in autumn and early winter.
These emerging mites will have distorted the experimental results - because - in percentage terms, the greater the overall number of mites present, the less this 'contaminating' figure of additional mites will have been - and conversely - it will have disproportionately 'contaminated' the figures from the reduced number of mites resulting from the second treatment. QED.
And - if there had been a 3rd treatment, then the percentage figures for 'effectiveness' would have been even lower - because the 'experimental contamination' of mites from emerging brood would have been proportionately higher, viz-a-viz the overall mite drop.