Correction on that 30%: Having posted earlier respond to soon, I realize that I may have confused still some more regarding the 30% concoction. I meant to say 30 gram Oxalic per liter (abbreviated in quart in my case) according to the following recipe: The dosage of the oxalic acid in the trickling method had to be reduced from originally 60g to 35g oxalic acid dihydrate per liter sugar syrup (1 part sugar + 1 part water), without an appreciable decrease of efficacy. At the same time, the bee tolerance of the trickling method was considerably increased. Below is the original source: http://www.apis.admin.ch/english/Themes/Varroa.htm A litter is *about* a quart; hence 30 gram of OA in a quart of syrup is the measure I used; therefore, 30% was inaccurate. Since measuring 30 gram per every quart of syrup was tedious, I used two-gallon syrup with 240 gram OA in one batch. Jim, help me with my math! (Please note that my 30 gram is less than the recommended 35 gram) Yoon Dick, you did not confuse anybody: I did. :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: -- Visit www.honeybeeworld.com/BEE-L for rules, FAQ and other info --- ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::