Oxalic acid with honey supers
The USDA has recently issued guidance expanding the use of oxalic acid for treatment of varroa mites in beehives. A determination has been made that oxalic acid, which occurs naturally in some plants such as beet leaves, tea, spinach and rhubarb, is safe for use with honey supers. They have determined the amount of residue in comb and honey is within acceptable tolerance levels. As a result, once finalized you will be able to use oxalic acid year-round and with honey supers on the hive.
“The label amendments expanding the in-hive use to year-round are still being finalized. Oxalic acid (API-Bioxal™) cannot be applied in hives when honey supers are on until the amended label or a supplemental label is provided on the product.....However, beekeepers can only legally begin using this product year-round once a supplemental label and/or the new amended label is included with the product packaging.”
USDA Feb 23, 2021
All treatments for bees must be done in compliance with the product label. The only approved methods are a solution method, spraying package bees and using a vaporizer. (Be sure to use approved PPE during applications). You must follow the instructions on the label for the product you have on hand.
Caution: This approval only applies to EPA registered oxalic acid (API-Bioxal™). It does NOT apply to wood bleach. “The use of oxalic acid that does not adhere to what is specified on the label…. or the use of application methods that differ would be considered a violation and is subject to EPA enforcement under FIFRA”. (Federal Insecticide, Fungicide, and Rodenticide Act)
For more information: https://www.regulations.gov/docket/EPA-HQ-OPP-2020-0176.