Checked my splits last night and notices a good number of bees with deformed wings from the cleverly named deformed wing virus. That is usually a sign that my enemy, Varroa Destructor, is gaining in numbers. So tonight I dug out my home brewed oxalic acid vaporizer and treated the two splits and their mother hive.
Waited until almost dark so the field bees were home. Treatment of each colony took about 3 minutes. Here you can see some of the OA vapor coming out the bottom of the hive. I toss a cloth on the landing board to keep both bees and the vapor inside.
In my experience, the mite drop will start tomorrow evening. Then a powdered sugar roll in 7-10 days to see what my mite count is.
That OA works very well. Are you going to do a full four treatment course?
I likely will not do the four treatments. I treat when the mite load is at 3/4 per hundred bees and when I have a brood break. I remember hearing in my queen raising class at the U of Mn, that only 15% of the Varroa Destructor will be on bees when there is sealed brood present. So waiting for a brood break increases the effectiveness. I'll do a sugar roll in a week or so, see what the load is, and decide on another treatment or not. My mother colony swarmed and is queenless (re-queening this weekend), and the nuc splits were re-queened but for whatever reason took a week off. Found the first eggs in both last night, so I have a good brood break in all three.