After treatment, two days ago, with OAV, I can only find 0-4 mites on the bottom board.
I treated 17 hives July 24, 2019 with Oxalic acid vapor using a provap 110volt set to 230F. I treated the rate of 1 gram per 10 frame langstrof deep: 2 grams per a double deep, 1 gram for 5 gram double nuc. Been doing same treatment for years except for my treatment free hives which all died last March. So this year all hives are treated. I gave up on treatment free, I can?t make it work; but to be clear: treatment free M. Bush and others are looked up to.
So where are all the mites? Did my treatment fail, all 17 hives, not likely but possible. I did treat last December with OAV with absent capped brood. In fact, 2018, I treated 5 times with OAV.
At this point, I am not sure why the absence of mites. Next time I see drone brood I will open the cells and look for mites.
I just can?t do an alcohol wash and subsequent mite count. I can?t kill the very bees I adore that trust me.
I am attaching a pic from October 26, 2018, last year. A pic of the bottom board that had a high mite count which the queen was replaced:
. Bottom board, 2 days after treatment with OAV, 2018. The white powder is diatonic earth for control of beetles.