Re: Critical Mass?
TF has been cool for 10 years or more. Very few queen breeders have made the effort to go completely treatment free. Commercial beekeepers don't have the financial resources to lose a large part of their operation on the way to treatment free. This sets up a vicious circle where the queen breeders continue to raise susceptible queens because the commercial beekeepers can't afford to get off the treadmill.
This is very similar to the situation with trachea mites in the early 1990's. The difference is that tracheamite resistance was available in the U.S. via Buckfast bees and other strains and races rapidly developed resistance. Nobody today worries about Acarine. Varroa mites are a tougher nut to crack, but they have been cracked and now the momentum is building for breeding mite resistant bees with all the traits commercial beekeepers need.
NW Alabama, 47 years, 22 colonies and growing, sideliner, treatment free since 2005, 14 frame square Dadant broodnest