In message <[log in to unmask]>, [log in to unmask] writes >Because the gestation >time for a drone is 24 days, 3 days longer than worker brood gestation, it >would appear that the female mite prefers to lay her mite eggs with drone >larva rather than worker larva, hence providing more food for her mite >progeny as well as perhaps more mites per bee cell than a worker bee cell. If I may add a small comment to George's point, I was taught that the varroa detects the drones by smell, which was said to be connected to the different feeding of the drone before capping, and a different pH. Hence the mechanism. >Hence, by entering one frame of drone size foundation into a brood nest and >removing it BEFORE the drones emerge would badly deplete the Varroa >population of a colony. The amount of drone brood foundation would depend on the number of mites available to enter cells at the time. Unless the population were very large, I suggest a whole frame would be too many. Only a small proportion of the drones would carry varroa and the ratio of effort to varroa loss would be too high. The Eastern Europeans developed a method where 3 frames with a portion of drone foundation were put in at intervals of a week and removed at the same interval. One round would be fine, covering 21 days. If I remember right, one third of a frame's worth or less was fine. Various approaches have been used from detachable sections, returned after freezing, to sections cut out. Super frames can be used but not together in a block, or the comb goes every which way across the bottoms. -- James Kilty