Hi Allen and Everyone,
"Powdered sugar" here in the US is a mixture of very finely ground sugar and corn starch also called confectioners sugar.
An article in the June issue of the American Bee Journal reported on using finely ground sugar for varroa control in colonies.  The sugar was dusted on the bees and the mites collected on sticky boards.
It appears that sugar will work if it is finely ground as Allen suggested.  I also suspect that corn starch which is a very fine powder and has a slippery feel between the fingers would work as well.
I have also heard that less powdered sugar ( one teaspoon - 5 ml scoop) is better than more as it is easier to separate out the mites but have not yet tried the technique myself.

blane

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Blane White
MN Dept of Agriculture
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