All the methods have some effect on Varroa mites. The reason has to do 
with spearmint and wintergreen which cause mite drop but you need 
screened bottoms for them to work. But many things cause mite drop. You 
are just buying some time if you are in the north or anywhere with 
confining winters.

You may end up with queen problems with the treatments.

Crisco is a Tracheal mite control and the only thing on the list that 
actually works and has good science behind it.

All the others have been around for a long time and those who use them 
say they work until their colonies die and they drop out of beekeeping.

Bill Truesdell
Bath, Maine

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