Hi Aaron and Everyone,
I have a couple of comments on Don's method.  It is actually a method developed not by Don but by researchers at USDA.  By dissolving the menthol in vegetable oil the surface area is greatly increased thereby greatly increasing the evaporation rate in cooler weather.  Yes it does work if done properly and yes it is legal since the applicator is using less that the menthol label calls for ( you can always use less than label rates legally, never more than label rates ).  Suggest looking up the actual article cited as Don's direction did not include a grill ( just be sure to do the heating outside ) and may ( don't remember here ) give a size roll on the paper towels.  Application is one per hive.  The menthol evaporates quickly so a second treatment 10 - 14 days later seems reasonable but may increase labor costs again you are using well below label rates of menthol.  Best time to treat with menthol is spring though not fall but this treatment will work earlier in the spring at cooler temperatures.  Note timing is determined by tracheal mite life cycle with better control being achieved with spring treatment than the same treatment in the fall.

Hope this helps.

blane



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Blane White
MN Dept of Agriculture
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