but do you have any record of colonies loss because you didnt treat with OA.?
If you mind to look Canadian hive losses, they has been huge. They have not CCD. Transition from Apistan to Formic acid has added the losses.
Even if thymol and formic acid are said to be 96% effective, it is not allways so. The results vary from 96 t0 70%.
If you have in Autumn 1000 mites, 4 % living mites means 40 mites. And it is is too much for next autumn.
If the efficacy is 70%, living mites will be after trestment 300 mites.
You must have under 10 mites after winter that they do not propagate themselves to 1000 mites' critical level.
So, if you get away 50 mites in January, it means 6000 mites in next September.
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Dishmop, you have read the results what guys get from trickling. They are huge sometimes and sometimes autumn treatment has been effective.
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If the result is 50 mites, we can look what happend when mites double them self in every month.
February 50
March....100
Ap.........200
May.......400 critical
June......800
July........1600
August....3 000
Sept-----6 000
. So when winter bees have reared, mite load is 6 time over critical.
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