Oxalic acid treatment of the bees

Its been a season with lots of varoa mites, and I have been treating my hive twice with formic acid already. Now it is time to do the oxalic acid treatment.

Oxalic acid works well on mites on the active bees in the hive, but it does not work on mites in the closed breading cells. Therfore oxalic acid should be used after be bees goes into the winter cluster and are no longer breading.

This weekend we had a bit of good weather Saturday (6/12), so I went to check the hive.

Yes, the bees were sitting in a small cluster and they were very inactive.

Oxalic acid treatment is quite simple. The solution used is

75g oxalic acid dihydrate
1 kg of sugar
1 L of water

Fortunately I could pick up some from my bee association, so I did not have to mix it myself. Anyway, of this solution 35 ml is used for one hive of consisting of 10 frames (12x10). The solution is added drop wise on the the bees allowing them to move around before dripping again. The bees do not really take notice of the treatment, so it is easy to do it quickly and close up the hive again before too much heat is lost.

Now I will just leave them undisturbed until spring and hope that they get well through the winter.