From the video: Practical Beekeeping Part 7
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Since the honey super is physically separated from the brood box by the solid divider, there is practically no brood in the honey super — all bees are on frames of honey and pollen. This is an ideal opportunity for treatment, because all varroa from both colonies (production and support) are on the bees, with no possibility of hiding in the brood.
The most effective agent for treating broodless bees is oxalic acid. A dose of 30 to 40 ml per colony is used.
White paper soaked in oil is placed on the solid divider to monitor varroa drop. This operation is performed at the beginning of the main honey flow (June 10–12), approximately 22 days from setup.
In the previous period, varroa is partially removed with drone combs, and this treatment finishes off the varroa right at the start of the main honey flow. Result: in August there is no need to fight varroa with chemical agents. One pad of formic acid can be added — more for hive disinfection than for varroa.
After treatment, the solid divider is removed and a queen excluder is placed. The bees are sprayed with mint tea for scent. A third empty super is added — and the honey producer for the main flow is set up.
Three honey supers can yield 45 to 60 kilograms of honey (15–20 kg per super, depending on the nectar flow). If the flow is not strong, one or two supers are sufficient.
There is an additional technique: the honey super with a young queen that has just started laying is placed on the bottom board, covered with a queen excluder, and the brood box is returned. The old queen is taken from the old brood box and a small nucleus is made, which is added to the support colony.
The production colony with a young queen gains the instinct for more intensive honey gathering — like a natural swarm. This is done at the beginning of the main honey flow because in the third period colonies reach their biological maximum of 5 to 7 kg of bees in mass, enabling them to exploit even the shortest nectar flow.