Great discussion, thanks all!

As previously posted I have been trying to find the formic fall dose and method that will work for me here in eastern WA. It is my belief that while formic can be a very effective varroa control tool it is the most climate, colony condition, specific of all our controls and very unforgiving when misapplied. One size does not fit all !! Temperature is most critical but colony size configuration and condition also play a large role. So I believe that together we need to develop dosing and placement standards that people can adapt to their local conditions.

Here is what worked for me after some exasperating trial and error. Local conditions during treatment window of late Aug. and Sept. are daytime highs in upper 80s, maybe into 90s and nighttime lows 30s and 40s. Don't know how much relative humidity matters but typically in low teens. All colonies are double deeps on solid bottoms inner cover and telescoping lid and 16 to 18 frames (big). The trick is to knock down the mites while not killing brood or ,heaven forbid queens, or disrupt egg laying during the crucial winter bee raising season.  I tested 6 colonies before treatment and tracked them after the first and second round. I then tested a lot more to confirm that the final result seemed to be valid. 

2 Dry-Loc 40 pads with 25ml 65% formic on the top bars right under the lid. That is a total dose each time of 50ml and given twice, a week apart. The pads are dry and being pulled apart after 3-4 days so I think this would be considered a "flash" treatment. Starting counts were not bad, and I think that is important, of 9 to 16 (3to 5%). 7 days latter just before the second round the counts were 3 to 5 (1to 2%) very encouraging and most important they were still actively raising brood and I saw eggs. 10 to 14 days after the second round all counts were 0s and 1s (<1%). I then tested 25 or 30 colonies and all but 1 (it had a good excuse) were <1%. 2 were in the process of superseding the queen. This again could be considered normal since it coincided with annual queen replacement but the timing seemed more than co-incidental. That is far better than the 15% queen loss and near total brood kill I experienced with MAQS and the lack of efficacy I experienced with 30ml single pads. The active brood nest in nearly all colonies was driven down to the bottom box as the top  newly emerged cells were being plugged. Again this is normal but noticeably enhanced by the formic pads I think. 

I'm going into winter with big populations of nearly mite free bees and a broad smile. Sleep tight.

Paul Hosticka
Dayton WA    

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