Natural infestation

Boot et al. (1992) designed a method that allows locating naturally infested cells. It is based on a one sided comb of which the cell walls where cut away from the bottom. The walls were then melted on a transparent sheet. These combs are consolidated by workers when replaced in the colonies and were accepted for oviposition by the queens. It might be necessary to cover the exposed side of the transparent sheet to prevent the bees building on it. Beetsma et al. (1994) also describe single rows of cells with two transparent walls that help locating and observing natural infestations