I am aware of the effectiveness of dribbling oxalic acid or vaporizing it to 
control mites during the broodless period but I have been unable to find any 
answers in the way that it kills mites.  I am wondering if in the case of 
vaporizing, mites coming into contact with the crystals are somehow affected 
in their ability to feed?  And if using the dribble method, is it also 
contact and if so, what is the point of mixing the acid with sugar syrup - 
or is it a case of bees ingesting the sugar syrup/oxalic acid mixture and 
then killing the mites feeding on the bees? 

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