Treating with formic before or after a split?
This is the beginning of my second year. I started with 2 hives. One survived, is doing well and I'm thinking I can split it to have two hives again. It's a double deep brood chamber and after some research and talking with beekeeping club members, I'm comfortable splitting the two deeps as a walk away split. The time for splitting is coming soon.
I also have decided to treat with formic acid in spring and fall. It's honey safe, mites can't become resistant to it, and is easier to apply than oxalic acid. It needs to be applied when day time highs are between 50 – 85 F, hence my time frame to treat in spring/fall. That works out best for reducing mite load going into honey production, and reducing mite load going into winter. I'll be testing for mite loads, but I'll be treating regardless.
So the question is should I treat before or after the split. Treatment takes two weeks, so I would treat, wait, then split. If I treat after splitting I feel like it would be best to wait until I verify the queenless colony has successfully raised a queen and that she's laying before starting treatment, which IIRC could take up to 3 or 4 weeks.