Center walls cell size 4.9mm

With the introduction of the central walls and the use of mobile construction in beekeeping, the cell size of the honeycomb cells on these central walls was increased. The idea behind it of larger cells - larger bees - more honey yield. It was also overlooked that the enlargement of the bees is associated with a higher susceptibility to disease. That was a problem which was good without the beekeeper Varroa mite. With emergence of Varroa mite the susceptibility to disease is hard to handle. This is shown by the annual winter losses to bee colonies. The step back to the likely original cell size of 4.9mm is said to reduce this sensitivity to the Varroa mite and lead to treatment-free Varro-resident bees.