it does work. as mite treatments go, it's one of the least damaging to the hive. it's what i use when i need to use something, but i am going into the 4th year treatment free (i hope). we'll see what loss spring brings.
Is this because you have the mites under control or you will let the weak ones die and the strong survive?? Just asking because this is the first year I haven't done any mite treatments. Usually I do the powdered sugar dusting, but never found the mite count to be high enough to bother, and now I just feel like leaving them alone and see what happens.