How does it work?
As a result of its coevolution with Apis cerana, varroa tends to favour drone cells to lay its eggs. Moreover, Apis mellifera drones have longer brood periods (24 days) than workers (21 days), which give varroa more time for a successful development. Since drones are bigger than workers, they also need bigger cells to develop. It is thus possible to lead the queen to lay eggs on certain frames only using comb foundations. After the workers have capped the cells and at last 4 days before the drones hatch, the frames are exchanged with new ones and either destroyed, cleaned or frozen. See the instructions by Tempelman in the references below for a detailed description of the procedure.
The advantage of freezing the frames is that the frames offer ready-made cells thus spare building works to the workers. According to Calderone the defrozen combs can be placed again in the hive as the dead drone larvae provide the workers with a source of proteins. Alternatively, the combs can be hung in a garden of a bird-lover, as the dead larvae will be greatly appreciated by birds, especially in the spring, when their young need this kind of energy-rich food (see also The Bird-Friendly Garden on this topic). The bird will then "take over" the work of cleaning the combs.
The method allows a mite population reduction up to 90-95% but not complete remediation. The efficiency depends on synergies with other environmental factors. A complementary treatment may be necessary, especially before the winter.
The timing of the operation may be delicate and require a lot of experience and dexterity. Wrong timing and the performance of the method on colonies that are too weak may lead to the loss of colonies. 
The elimination of drone cells may result in the selection of varroa mites that breed in female bee larvae cells, thus the method may end up to be ineffective and even to worsen the problem.
This method destroys large populations of drones, which reduces the gene pool, and the chances of proper fecundation of queens, thus may affect queen productivity and result in weaker successive bee generations. This aspect is particularly critical in the spring before the queen's nuptial flight.
Ready-made comb foundations are available from beekeeping material suppliers. Two drone combs per hive are sufficient. Nevertheless, note that commercially available comb foundations may be contaminated with pesticide residues (see Veterinary Treatments).
The method is relatively complex and labour-intensive and requires regular looking-after.
The colonies treated with this method have to be strong enough in the spring, unless the method would represent a further burden on the colony.
The method may not always provide sufficient removal and a complementary treatment is often required before the winter.
Four comb exchanges in a year are more than enough to obtain satisfactory mite population reduction, therefore do not exceed this number to avoid the depletion of drone populations.
Have frozen combs defrozen before inserting them into the hive. Do not insert old combs if any other problem (e.g. foul larvae) has been detected on them. If cleaned, the combs have to be stored in a dry place to avoid the development of fungi.
- ↑ 1.0 1.1 1.2 1.3 1.4 Tempelman J., 2007: Varroa Mites and how to catch them. In: Apiservice. http://www.apiservices.com/articles/us/varroa_drone_method.htm
- ↑ 2.0 2.1 van Dugteren P. 2009: personal correspondence per email with Piet van Dugteren, biologist and beekeeper, on 2009-04-19
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 Calderone N., 2005: Drone Brood Removal for the Management of Varroa destructor. http://www.masterbeekeeper.org/pdf/dronecomb_exchange.pdf
- ↑ Hominda J., 2006: Message From the President. In: Buzzword, West Sound Beekeepers Association. http://www.westsoundbees.org/newsletters/april_2006.pdf
- ↑ van Dugteren P. 2009: personal correspondence per email with Piet van Dugteren, biologist and beekeeper, on 2009-12-28