Bugs, Blooms and Vittles
By Chandra Mattingly
In a previous blog, I mentioned fogging my honeybee hives with mineral oil to suppress mites. SIBA member Joan Chester, Independence, Ky., has started fogging her own hives with mineral oil to which she has added mint oil and asked me what I do. So here is an explanation and some photos taken by my spouse Bob Mattingly.
But first, a disclaimer. When he spoke to the club in February, Purdue entomologist Dr. Greg Hunt said studies have shown fogging with mineral oil has no effect on mite populations. All I know is that all three of my hives survived last winter with strong populations and that I've had the same strain of honeybees since at least 2001. I can't say I've never lost hives over winter since then, but it's been a rare occurrence, and only with hives I knew were weak going into the winter. (I just hope I'm not jinxing my bees by writing this!)
My fogging method comes from Aurora beekeeper John Griffith some years back, and my equipment courtesy of my spouse per John's instructions.
Take a super, cover one side with plywood or another material and cut a just-over one-inch hole in one side. Purchase an insect fogger and unscrew the spray end. Drill a hole just large enough for the spray end to fit through in the solid end of a one-inch diameter copper cap. The cap should fit into the hole in the super. Slide the copper cap over the spray nozzle and re-attach the spray end inside the cap. Put mineral oil in the fogger's container and light the fogger. Tuck a plastic bag or piece of cloth in your pocket.
Now you're ready to go! In your apiary, remove the cover and inner cover from one of your hives and replace with the modified super. Apply mineral oil fog through the hole – it should come out in great puffs of white smoke and the super will leak some of it. In just a few minutes, you will see the fog seeping out the hive's entrance. Plug the hole in the super with the bag or cloth from your pocket. Wait about 10 minutes before removing the modified super and replacing the inner and outer covers, to allow the oil fog to disperse through the hive.
We've made two modified supers, both from comb honey supers, so I treat two hives at a time. I “oil” the hives every two to two and a half weeks from March or April through the warm weather in the fall. The idea is to hit each brood cycle.
Afterward, I see bees cleaning the oil off themselves. I don't know if the oil actually suffocates some of the mites – I would think it might work that way on tracheal mites – or if the cleaning it stimulates the bees to bite and remove Varroa mites. All I know is I've been doing this for a number of years, have never done a mite count, and the bees seem to maintain strong hives.