> One of our regulars wrote this back in 1999:
> "Destroying older combs that are still in good shape is another of those
> things small-time beekeepers do to make sure that they stay small-time."
>
> Yet comb renewal has become a popular call - does anyone have concrete 
> evidence of a benefit from comb renewal, beyond the possibility of relief 
> from Foulbrood, Nosema and perhaps Chalkbrood?

I wouldn't want to argue with that guy, but one thing has changed greatly in 
the meantime, and that is the known chemical load in beehives, much of it 
applied by the beekeeper with or without the blessings of the extension 
people and regulators.

Many beekeepers are putting some pretty toxic things into their hives, and 
there is always the danger of chemicals from the environment, too, and so 
comb contamination is a prime suspect whenever anything is out of whack.

The legal treatments are -- with the exception IMO of organic acids and some 
and by no means all essential oils -- bad enough, but many have tried using 
other formulations as well.

Since most won't admit it, for fear of regulatory action, the assumption 
made, unless proven otherwise is that all hives contain toxic combs.  Thus 
the advice to change combs.

Absent chemical contamination, there are plenty of proven ways to 
decontaminate combs that are suspected of carrying all but the most 
persistent bee diseases, using acid fumigation or even simple airing out, 
and radiation will deal with even that.

Good drawn combs are an essential asset to a beekeeper, in the North, at 
least, (maybe not so much in the South) and should be conserved, except when 
known or suspected  to be contaminated with substances like coumaphos.

Good diseased comb should be irradiated, aired out, or fumigated -- or, 
barring AFB, given to a strong hive on a good flow early in the season.

IMO. YMMV. 

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