Hi Dave
Timing the interruption of the  brood  cycle to reduce Varroa.

Two years ago I started to try and trap varroa in drone comb by a german 
method, eg. place an empty frame, no foundation or starter strip at the 
back or last but one. In my case 16"x10" frames.
I had no trouble getting the bees to draw a perfect frame of drone and 
fill it with brood, I have done this three times between mid April and 
late May. After May they only draw half way then put honey in it. Each 
time I remove a comb I give another empty frame. I have never seen a 
single mite in any of these combs, by June last year I had 4 x 25liter 
buckets of uncapped drone comb to burn.(I don't keep chickens). There is 
a small amount of natualy converted drone comb in the hive.
Both my Seasonal bee inspector and a retired freind who was apiarist at 
Rothhampstead for twenty + years said they had never seen anything like 
it! I am comming to the conclusion it must be a timing thing, but so far 
I have no solution.
Just to confound all of this, a freind caught a swarm but was a frame of 
foundation short so I gave him a drawn drone comb and placed it one 
space in from the front, when the drone comb was capped we uncapped it 
and surprise it was crawling with mites, three or more to a cell.
Regards Andy

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