This is the second full hive treatment with oxalic acid to combat mites. Normally I would do a third but not sure - the mite levels are likely within acceptable levels now. Bear in mind that I had rhubarb leaves in the hives already prior to two doses of acid and my smoker contains rhubarb leaves. The bees have been exposed to steady levels of oxalic. I'll evaluate next week. Thus far, the hives seem to be doing well with no immediately evident negative impacts of treatment to the hives.